Merge branch 'master' of github.com:eugenp/tutorials

algorithms-miscellaneous-6/pom.xml

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>algorithms-miscellaneous-6</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>algorithms-miscellaneous-6</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+</project>

algorithms-miscellaneous-6/src/main/java/com/baeldung/algorithms/gradientdescent/GradientDescent.java

@@ -0,0 +1,33 @@
+package com.baeldung.algorithms.gradientdescent;
+
+import java.util.function.Function;
+
+public class GradientDescent {
+
+    private final double precision = 0.000001;
+
+    public double findLocalMinimum(Function<Double, Double> f, double initialX) {
+        double stepCoefficient = 0.1;
+        double previousStep = 1.0;
+        double currentX = initialX;
+        double previousX = initialX;
+        double previousY = f.apply(previousX);
+        int iter = 100;
+
+        currentX += stepCoefficient * previousY;
+
+        while (previousStep > precision && iter > 0) {
+            iter--;
+            double currentY = f.apply(currentX);
+            if (currentY > previousY) {
+                stepCoefficient = -stepCoefficient / 2;
+            }
+            previousX = currentX;
+            currentX += stepCoefficient * previousY;
+            previousY = currentY;
+            previousStep = StrictMath.abs(currentX - previousX);
+        }
+        return currentX;
+    }
+
+}

algorithms-miscellaneous-6/src/test/java/com/baeldung/algorithms/gradientdescent/GradientDescentUnitTest.java

@@ -0,0 +1,20 @@
+package com.baeldung.algorithms.gradientdescent;
+
+import static org.junit.Assert.assertTrue;
+
+import java.util.function.Function;
+
+import org.junit.Test;
+
+public class GradientDescentUnitTest {
+
+    @Test
+    public void givenFunction_whenStartingPointIsOne_thenLocalMinimumIsFound() {
+        Function<Double, Double> df = x ->
+            StrictMath.abs(StrictMath.pow(x, 3)) - (3 * StrictMath.pow(x, 2)) + x;
+        GradientDescent gd = new GradientDescent();
+        double res = gd.findLocalMinimum(df, 1);
+        assertTrue(res > 1.78);
+        assertTrue(res < 1.84);
+    }
+}

core-java-modules/core-java-concurrency-basic-2/src/test/java/com/baeldung/concurrent/atomic/AtomicMarkableReferenceUnitTest.java

@@ -0,0 +1,189 @@
+package com.baeldung.concurrent.atomic;
+
+import java.util.concurrent.atomic.AtomicMarkableReference;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public class AtomicMarkableReferenceUnitTest {
+
+    class Employee {
+        private int id;
+        private String name;
+
+        Employee(int id, String name) {
+            this.id = id;
+            this.name = name;
+        }
+
+        public int getId() {
+            return id;
+        }
+
+        public void setId(int id) {
+            this.id = id;
+        }
+
+        public String getName() {
+            return name;
+        }
+
+        public void setName(String name) {
+            this.name = name;
+        }
+    }
+
+    @Test
+    void givenMarkValueAsTrue_whenUsingIsMarkedMethod_thenMarkValueShouldBeTrue() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+
+        Assertions.assertTrue(employeeNode.isMarked());
+    }
+
+    @Test
+    void givenMarkValueAsFalse_whenUsingIsMarkedMethod_thenMarkValueShouldBeFalse() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, false);
+
+        Assertions.assertFalse(employeeNode.isMarked());
+    }
+
+    @Test
+    void whenUsingGetReferenceMethod_thenCurrentReferenceShouldBeReturned() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+
+        Assertions.assertEquals(employee, employeeNode.getReference());
+    }
+
+    @Test
+    void whenUsingGetMethod_thenCurrentReferenceAndMarkShouldBeReturned() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+
+        boolean[] markHolder = new boolean[1];
+        Employee currentEmployee = employeeNode.get(markHolder);
+
+        Assertions.assertEquals(employee, currentEmployee);
+        Assertions.assertTrue(markHolder[0]);
+    }
+
+    @Test
+    void givenNewReferenceAndMark_whenUsingSetMethod_thenCurrentReferenceAndMarkShouldBeUpdated() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+
+        Employee newEmployee = new Employee(124, "John");
+        employeeNode.set(newEmployee, false);
+
+        Assertions.assertEquals(newEmployee, employeeNode.getReference());
+        Assertions.assertFalse(employeeNode.isMarked());
+    }
+
+    @Test
+    void givenTheSameObjectReference_whenUsingAttemptMarkMethod_thenMarkShouldBeUpdated() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+
+        Assertions.assertTrue(employeeNode.attemptMark(employee, false));
+        Assertions.assertFalse(employeeNode.isMarked());
+    }
+
+    @Test
+    void givenDifferentObjectReference_whenUsingAttemptMarkMethod_thenMarkShouldNotBeUpdated() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+        Employee expectedEmployee = new Employee(123, "Mike");
+
+        Assertions.assertFalse(employeeNode.attemptMark(expectedEmployee, false));
+        Assertions.assertTrue(employeeNode.isMarked());
+    }
+
+    @Test
+    void givenCurrentReferenceAndCurrentMark_whenUsingCompareAndSet_thenReferenceAndMarkShouldBeUpdated() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+        Employee newEmployee = new Employee(124, "John");
+
+        Assertions.assertTrue(employeeNode.compareAndSet(employee, newEmployee, true, false));
+        Assertions.assertEquals(newEmployee, employeeNode.getReference());
+        Assertions.assertFalse(employeeNode.isMarked());
+    }
+
+    @Test
+    void givenNotCurrentReferenceAndCurrentMark_whenUsingCompareAndSet_thenReferenceAndMarkShouldNotBeUpdated() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+        Employee newEmployee = new Employee(124, "John");
+
+        Assertions.assertFalse(employeeNode.compareAndSet(new Employee(1234, "Steve"), newEmployee, true, false));
+        Assertions.assertEquals(employee, employeeNode.getReference());
+        Assertions.assertTrue(employeeNode.isMarked());
+    }
+
+    @Test
+    void givenCurrentReferenceAndNotCurrentMark_whenUsingCompareAndSet_thenReferenceAndMarkShouldNotBeUpdated() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+        Employee newEmployee = new Employee(124, "John");
+
+        Assertions.assertFalse(employeeNode.compareAndSet(employee, newEmployee, false, true));
+        Assertions.assertEquals(employee, employeeNode.getReference());
+        Assertions.assertTrue(employeeNode.isMarked());
+    }
+
+    @Test
+    void givenNotCurrentReferenceAndNotCurrentMark_whenUsingCompareAndSet_thenReferenceAndMarkShouldNotBeUpdated() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+        Employee newEmployee = new Employee(124, "John");
+
+        Assertions.assertFalse(employeeNode.compareAndSet(new Employee(1234, "Steve"), newEmployee, false, true));
+        Assertions.assertEquals(employee, employeeNode.getReference());
+        Assertions.assertTrue(employeeNode.isMarked());
+    }
+
+    @Test
+    void givenCurrentReferenceAndCurrentMark_whenUsingWeakCompareAndSet_thenReferenceAndMarkShouldBeUpdated() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+        Employee newEmployee = new Employee(124, "John");
+
+        Assertions.assertTrue(employeeNode.weakCompareAndSet(employee, newEmployee, true, false));
+        Assertions.assertEquals(newEmployee, employeeNode.getReference());
+        Assertions.assertFalse(employeeNode.isMarked());
+    }
+
+    @Test
+    void givenNotCurrentReferenceAndCurrentMark_whenUsingWeakCompareAndSet_thenReferenceAndMarkShouldNotBeUpdated() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+        Employee newEmployee = new Employee(124, "John");
+
+        Assertions.assertFalse(employeeNode.weakCompareAndSet(new Employee(1234, "Steve"), newEmployee, true, false));
+        Assertions.assertEquals(employee, employeeNode.getReference());
+        Assertions.assertTrue(employeeNode.isMarked());
+    }
+
+    @Test
+    void givenCurrentReferenceAndNotCurrentMark_whenUsingWeakCompareAndSet_thenReferenceAndMarkShouldNotBeUpdated() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+        Employee newEmployee = new Employee(124, "John");
+
+        Assertions.assertFalse(employeeNode.weakCompareAndSet(employee, newEmployee, false, true));
+        Assertions.assertEquals(employee, employeeNode.getReference());
+        Assertions.assertTrue(employeeNode.isMarked());
+    }
+
+    @Test
+    void givenNotCurrentReferenceAndNotCurrentMark_whenUsingWeakCompareAndSet_thenReferenceAndMarkShouldNotBeUpdated() {
+        Employee employee = new Employee(123, "Mike");
+        AtomicMarkableReference<Employee> employeeNode = new AtomicMarkableReference<Employee>(employee, true);
+        Employee newEmployee = new Employee(124, "John");
+
+        Assertions.assertFalse(employeeNode.weakCompareAndSet(new Employee(1234, "Steve"), newEmployee, false, true));
+        Assertions.assertEquals(employee, employeeNode.getReference());
+        Assertions.assertTrue(employeeNode.isMarked());
+    }
+}

pom.xml

@@ -342,6 +342,7 @@
                 <module>algorithms-miscellaneous-3</module>
                 <module>algorithms-miscellaneous-4</module>
                 <module>algorithms-miscellaneous-5</module>
+                <module>algorithms-miscellaneous-6</module>
                 <module>algorithms-searching</module>
                 <module>algorithms-sorting</module>
                 <module>algorithms-sorting-2</module>
@@ -853,6 +854,7 @@
                 <module>algorithms-miscellaneous-3</module>
                 <module>algorithms-miscellaneous-4</module>
                 <module>algorithms-miscellaneous-5</module>
+                <module>algorithms-miscellaneous-6</module>
                 <module>algorithms-searching</module>
                 <module>algorithms-sorting</module>
                 <module>algorithms-sorting-2</module>

spring-5-reactive-client/pom.xml

@@ -92,8 +92,8 @@
         </dependency>
         <dependency>
             <groupId>com.github.tomakehurst</groupId>
-            <artifactId>wiremock</artifactId>
-            <version>2.24.1</version>
+            <artifactId>wiremock-standalone</artifactId>
+            <version>2.26.0</version>
             <scope>test</scope>
         </dependency>
 

spring-5-reactive-client/src/test/java/com/baeldung/reactive/ReactiveIntegrationTest.java

@@ -1,37 +1,67 @@
 package com.baeldung.reactive;
 
-import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.api.Test;
+import static com.github.tomakehurst.wiremock.client.WireMock.aResponse;
+import static com.github.tomakehurst.wiremock.client.WireMock.configureFor;
+import static com.github.tomakehurst.wiremock.client.WireMock.get;
+import static com.github.tomakehurst.wiremock.client.WireMock.stubFor;
+import static com.github.tomakehurst.wiremock.client.WireMock.urlEqualTo;
+import static com.github.tomakehurst.wiremock.core.WireMockConfiguration.wireMockConfig;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
 import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.web.reactive.function.client.ClientResponse;
 import org.springframework.web.reactive.function.client.WebClient;
 
 import com.baeldung.reactive.model.Foo;
+import com.github.tomakehurst.wiremock.WireMockServer;
 
 import reactor.core.publisher.Mono;
 
+@RunWith(SpringRunner.class)
 @SpringBootTest
 public class ReactiveIntegrationTest {
 
     private WebClient client;
-
-    @BeforeEach
-    public void before() {
-        client = WebClient.create("http://localhost:8080");
+    private int singleRequestTime = 1000;
+    private WireMockServer wireMockServer;
+    
+    @Before
+    public void setup() {
+        wireMockServer = new WireMockServer(wireMockConfig().dynamicPort());
+        wireMockServer.start();
+        configureFor("localhost", wireMockServer.port());
+        client = WebClient.create("http://localhost:" + wireMockServer.port());
     }
 
-    //
+    @After
+    public void tearDown() {
+        wireMockServer.stop();
+    }
 
     @Test
     public void whenMonoReactiveEndpointIsConsumed_thenCorrectOutput() {
-        final Mono<ClientResponse> fooMono = client.get().uri("/foos/123").exchange().log();
+        stubFor(get(urlEqualTo("/foo/123")).willReturn(aResponse().withFixedDelay(singleRequestTime)
+            .withStatus(200)
+            .withHeader("Content-Type", "application/json")
+            .withBody("{\"id\":123, \"name\":\"foo\"}")));
+        
+        final Mono<ClientResponse> fooMono = client.get().uri("/foo/123").exchange().log();
 
         System.out.println(fooMono.subscribe());
     }
 
     @Test
     public void whenFluxReactiveEndpointIsConsumed_thenCorrectOutput() throws InterruptedException {
-        client.get().uri("/foos")
+        stubFor(get(urlEqualTo("/foo")).willReturn(aResponse().withFixedDelay(singleRequestTime)
+            .withStatus(200)
+            .withHeader("Content-Type", "application/json")
+            .withBody("{\"id\":1, \"name\":\"foo\"}")));
+        
+        client.get().uri("/foo")
             .retrieve()
             .bodyToFlux(Foo.class).log()
             .subscribe(System.out::println);

spring-5-reactive-client/src/test/java/com/baeldung/reactive/webclient/simultaneous/ClientIntegrationTest.java

@@ -5,6 +5,7 @@ import org.junit.Before;
 import org.junit.After;
 import org.junit.runner.RunWith;
 import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.annotation.DirtiesContext;
 import org.springframework.test.context.junit4.SpringRunner;
 import com.github.tomakehurst.wiremock.WireMockServer;
 
@@ -19,15 +20,19 @@ import static org.junit.Assert.assertEquals;
 
 @RunWith(SpringRunner.class)
 @SpringBootTest
+@DirtiesContext
 public class ClientIntegrationTest {
 
     private WireMockServer wireMockServer;
 
+    private Client client;
+    
     @Before
     public void setup() {
-        wireMockServer = new WireMockServer(wireMockConfig().port(8089));
+        wireMockServer = new WireMockServer(wireMockConfig().dynamicPort());
         wireMockServer.start();
         configureFor("localhost", wireMockServer.port());
+        client = new Client("http://localhost:" + wireMockServer.port());
     }
 
     @After
@@ -52,8 +57,6 @@ public class ClientIntegrationTest {
             .boxed()
             .collect(Collectors.toList());
 
-        Client client = new Client("http://localhost:8089");
-
         // Act
         long start = System.currentTimeMillis();
         List<User> users = client.fetchUsers(userIds)

spring-swagger-codegen/pom.xml

@@ -15,6 +15,7 @@
 
     <modules>
         <module>spring-swagger-codegen-api-client</module>
+        <module>spring-openapi-generator-api-client</module>
         <module>spring-swagger-codegen-app</module>
     </modules>
 

spring-swagger-codegen/spring-openapi-generator-api-client/.openapi-generator-ignore

@@ -0,0 +1,23 @@
+# OpenAPI Generator Ignore
+# Generated by openapi-generator https://github.com/openapitools/openapi-generator
+
+# Use this file to prevent files from being overwritten by the generator.
+# The patterns follow closely to .gitignore or .dockerignore.
+
+# As an example, the C# client generator defines ApiClient.cs.
+# You can make changes and tell OpenAPI Generator to ignore just this file by uncommenting the following line:
+#ApiClient.cs
+
+# You can match any string of characters against a directory, file or extension with a single asterisk (*):
+#foo/*/qux
+# The above matches foo/bar/qux and foo/baz/qux, but not foo/bar/baz/qux
+
+# You can recursively match patterns against a directory, file or extension with a double asterisk (**):
+#foo/**/qux
+# This matches foo/bar/qux, foo/baz/qux, and foo/bar/baz/qux
+
+# You can also negate patterns with an exclamation (!).
+# For example, you can ignore all files in a docs folder with the file extension .md:
+#docs/*.md
+# Then explicitly reverse the ignore rule for a single file:
+#!docs/README.md

spring-swagger-codegen/spring-openapi-generator-api-client/.openapi-generator/VERSION

@@ -0,0 +1 @@
+4.2.3

spring-swagger-codegen/spring-openapi-generator-api-client/.travis.yml

@@ -0,0 +1,22 @@
+#
+# Generated by OpenAPI Generator: https://openapi-generator.tech
+#
+# Ref: https://docs.travis-ci.com/user/languages/java/
+#
+language: java
+jdk:
+  - openjdk12
+  - openjdk11
+  - openjdk10
+  - openjdk9
+  - openjdk8
+before_install:
+  # ensure gradlew has proper permission
+  - chmod a+x ./gradlew
+script:
+  # test using maven
+  #- mvn test
+  # test using gradle
+  - gradle test
+  # test using sbt 
+  # - sbt test

spring-swagger-codegen/spring-openapi-generator-api-client/README.md

@@ -0,0 +1,174 @@
+# spring-openapi-generator-api-client
+
+Swagger Petstore
+
+- API version: 1.0.3
+
+- Build date: 2020-03-15T06:14:01.568992-05:00[America/Chicago]
+
+This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+
+
+*Automatically generated by the [OpenAPI Generator](https://openapi-generator.tech)*
+
+## Requirements
+
+Building the API client library requires:
+
+1. Java 1.8+
+2. Maven/Gradle
+
+## Installation
+
+To install the API client library to your local Maven repository, simply execute:
+
+```shell
+mvn clean install
+```
+
+To deploy it to a remote Maven repository instead, configure the settings of the repository and execute:
+
+```shell
+mvn clean deploy
+```
+
+Refer to the [OSSRH Guide](http://central.sonatype.org/pages/ossrh-guide.html) for more information.
+
+### Maven users
+
+Add this dependency to your project's POM:
+
+```xml
+<dependency>
+  <groupId>com.baeldung</groupId>
+  <artifactId>spring-openapi-generator-api-client</artifactId>
+  <version>0.0.1-SNAPSHOT</version>
+  <scope>compile</scope>
+</dependency>
+```
+
+### Gradle users
+
+Add this dependency to your project's build file:
+
+```groovy
+compile "com.baeldung:spring-openapi-generator-api-client:0.0.1-SNAPSHOT"
+```
+
+### Others
+
+At first generate the JAR by executing:
+
+```shell
+mvn clean package
+```
+
+Then manually install the following JARs:
+
+- `target/spring-openapi-generator-api-client-0.0.1-SNAPSHOT.jar`
+- `target/lib/*.jar`
+
+## Getting Started
+
+Please follow the [installation](#installation) instruction and execute the following Java code:
+
+```java
+
+import com.baeldung.petstore.client.invoker.*;
+import com.baeldung.petstore.client.invoker.auth.*;
+import com.baeldung.petstore.client.model.*;
+import com.baeldung.petstore.client.api.PetApi;
+
+public class PetApiExample {
+
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+        
+        // Configure OAuth2 access token for authorization: petstore_auth
+        OAuth petstore_auth = (OAuth) defaultClient.getAuthentication("petstore_auth");
+        petstore_auth.setAccessToken("YOUR ACCESS TOKEN");
+
+        PetApi apiInstance = new PetApi(defaultClient);
+        Pet body = new Pet(); // Pet | Pet object that needs to be added to the store
+        try {
+            apiInstance.addPet(body);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling PetApi#addPet");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+
+```
+
+## Documentation for API Endpoints
+
+All URIs are relative to *https://petstore.swagger.io/v2*
+
+Class | Method | HTTP request | Description
+------------ | ------------- | ------------- | -------------
+*PetApi* | [**addPet**](docs/PetApi.md#addPet) | **POST** /pet | Add a new pet to the store
+*PetApi* | [**deletePet**](docs/PetApi.md#deletePet) | **DELETE** /pet/{petId} | Deletes a pet
+*PetApi* | [**findPetsByStatus**](docs/PetApi.md#findPetsByStatus) | **GET** /pet/findByStatus | Finds Pets by status
+*PetApi* | [**findPetsByTags**](docs/PetApi.md#findPetsByTags) | **GET** /pet/findByTags | Finds Pets by tags
+*PetApi* | [**getPetById**](docs/PetApi.md#getPetById) | **GET** /pet/{petId} | Find pet by ID
+*PetApi* | [**updatePet**](docs/PetApi.md#updatePet) | **PUT** /pet | Update an existing pet
+*PetApi* | [**updatePetWithForm**](docs/PetApi.md#updatePetWithForm) | **POST** /pet/{petId} | Updates a pet in the store with form data
+*PetApi* | [**uploadFile**](docs/PetApi.md#uploadFile) | **POST** /pet/{petId}/uploadImage | uploads an image
+*StoreApi* | [**deleteOrder**](docs/StoreApi.md#deleteOrder) | **DELETE** /store/order/{orderId} | Delete purchase order by ID
+*StoreApi* | [**getInventory**](docs/StoreApi.md#getInventory) | **GET** /store/inventory | Returns pet inventories by status
+*StoreApi* | [**getOrderById**](docs/StoreApi.md#getOrderById) | **GET** /store/order/{orderId} | Find purchase order by ID
+*StoreApi* | [**placeOrder**](docs/StoreApi.md#placeOrder) | **POST** /store/order | Place an order for a pet
+*UserApi* | [**createUser**](docs/UserApi.md#createUser) | **POST** /user | Create user
+*UserApi* | [**createUsersWithArrayInput**](docs/UserApi.md#createUsersWithArrayInput) | **POST** /user/createWithArray | Creates list of users with given input array
+*UserApi* | [**createUsersWithListInput**](docs/UserApi.md#createUsersWithListInput) | **POST** /user/createWithList | Creates list of users with given input array
+*UserApi* | [**deleteUser**](docs/UserApi.md#deleteUser) | **DELETE** /user/{username} | Delete user
+*UserApi* | [**getUserByName**](docs/UserApi.md#getUserByName) | **GET** /user/{username} | Get user by user name
+*UserApi* | [**loginUser**](docs/UserApi.md#loginUser) | **GET** /user/login | Logs user into the system
+*UserApi* | [**logoutUser**](docs/UserApi.md#logoutUser) | **GET** /user/logout | Logs out current logged in user session
+*UserApi* | [**updateUser**](docs/UserApi.md#updateUser) | **PUT** /user/{username} | Updated user
+
+
+## Documentation for Models
+
+ - [Category](docs/Category.md)
+ - [ModelApiResponse](docs/ModelApiResponse.md)
+ - [Order](docs/Order.md)
+ - [Pet](docs/Pet.md)
+ - [Tag](docs/Tag.md)
+ - [User](docs/User.md)
+
+
+## Documentation for Authorization
+
+Authentication schemes defined for the API:
+### api_key
+
+
+- **Type**: API key
+- **API key parameter name**: api_key
+- **Location**: HTTP header
+
+### petstore_auth
+
+
+- **Type**: OAuth
+- **Flow**: implicit
+- **Authorization URL**: https://petstore.swagger.io/oauth/authorize
+- **Scopes**: 
+  - read:pets: read your pets
+  - write:pets: modify pets in your account
+
+
+## Recommendation
+
+It's recommended to create an instance of `ApiClient` per thread in a multithreaded environment to avoid any potential issues.
+
+## Author
+
+apiteam@swagger.io
+

spring-swagger-codegen/spring-openapi-generator-api-client/build.gradle

@@ -0,0 +1,120 @@
+apply plugin: 'idea'
+apply plugin: 'eclipse'
+
+group = 'com.baeldung'
+version = '0.0.1-SNAPSHOT'
+
+buildscript {
+    repositories {
+        maven { url "https://repo1.maven.org/maven2" }
+        jcenter()
+    }
+    dependencies {
+        classpath 'com.android.tools.build:gradle:1.5.+'
+        classpath 'com.github.dcendents:android-maven-gradle-plugin:1.3'
+    }
+}
+
+repositories {
+    jcenter()
+}
+
+
+if(hasProperty('target') && target == 'android') {
+
+    apply plugin: 'com.android.library'
+    apply plugin: 'com.github.dcendents.android-maven'
+    
+    android {
+        compileSdkVersion 23
+        buildToolsVersion '23.0.2'
+        defaultConfig {
+            minSdkVersion 14
+            targetSdkVersion 22
+        }
+        compileOptions {
+            sourceCompatibility JavaVersion.VERSION_1_8
+            targetCompatibility JavaVersion.VERSION_1_8
+        }
+    
+        // Rename the aar correctly
+        libraryVariants.all { variant ->
+            variant.outputs.each { output ->
+                def outputFile = output.outputFile
+                if (outputFile != null && outputFile.name.endsWith('.aar')) {
+                    def fileName = "${project.name}-${variant.baseName}-${version}.aar"
+                    output.outputFile = new File(outputFile.parent, fileName)
+                }
+            }
+        }
+
+        dependencies {
+            provided 'javax.annotation:jsr250-api:1.0'
+        }
+    }
+    
+    afterEvaluate {
+        android.libraryVariants.all { variant ->
+            def task = project.tasks.create "jar${variant.name.capitalize()}", Jar
+            task.description = "Create jar artifact for ${variant.name}"
+            task.dependsOn variant.javaCompile
+            task.from variant.javaCompile.destinationDir
+            task.destinationDir = project.file("${project.buildDir}/outputs/jar")
+            task.archiveName = "${project.name}-${variant.baseName}-${version}.jar"
+            artifacts.add('archives', task);
+        }
+    }
+    
+    task sourcesJar(type: Jar) {
+        from android.sourceSets.main.java.srcDirs
+        classifier = 'sources'
+    }
+    
+    artifacts {
+        archives sourcesJar
+    }
+
+} else {
+
+    apply plugin: 'java'
+    apply plugin: 'maven'
+
+    sourceCompatibility = JavaVersion.VERSION_1_8
+    targetCompatibility = JavaVersion.VERSION_1_8
+
+    install {
+        repositories.mavenInstaller {
+            pom.artifactId = 'spring-openapi-generator-api-client'
+        }
+    }
+    
+    task execute(type:JavaExec) {
+       main = System.getProperty('mainClass')
+       classpath = sourceSets.main.runtimeClasspath
+    }
+}
+
+ext {
+    swagger_annotations_version = "1.5.22"
+    jackson_version = "2.10.1"
+    jackson_databind_version = "2.10.1"
+    jackson_databind_nullable_version = "0.2.1"
+    spring_web_version = "4.3.9.RELEASE"
+    jodatime_version = "2.9.9"
+    junit_version = "4.13"
+    jackson_threeten_version = "2.9.10"
+}
+
+dependencies {
+    compile "io.swagger:swagger-annotations:$swagger_annotations_version"
+    compile "com.google.code.findbugs:jsr305:3.0.2"
+    compile "org.springframework:spring-web:$spring_web_version"
+    compile "com.fasterxml.jackson.core:jackson-core:$jackson_version"
+    compile "com.fasterxml.jackson.core:jackson-annotations:$jackson_version"
+    compile "com.fasterxml.jackson.core:jackson-databind:$jackson_databind_version"
+    compile "com.fasterxml.jackson.jaxrs:jackson-jaxrs-json-provider:$jackson_version"
+    compile "org.openapitools:jackson-databind-nullable:$jackson_databind_nullable_version"
+    compile "com.fasterxml.jackson.datatype:jackson-datatype-jsr310:$jackson_version"
+    compile "com.github.joschi.jackson:jackson-datatype-threetenbp:$jackson_threeten_version"
+    testCompile "junit:junit:$junit_version"
+}

spring-swagger-codegen/spring-openapi-generator-api-client/docs/Category.md

@@ -0,0 +1,13 @@
+
+
+# Category
+
+## Properties
+
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+**id** | **Long** |  |  [optional]
+**name** | **String** |  |  [optional]
+
+
+

spring-swagger-codegen/spring-openapi-generator-api-client/docs/ModelApiResponse.md

@@ -0,0 +1,14 @@
+
+
+# ModelApiResponse
+
+## Properties
+
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+**code** | **Integer** |  |  [optional]
+**type** | **String** |  |  [optional]
+**message** | **String** |  |  [optional]
+
+
+

spring-swagger-codegen/spring-openapi-generator-api-client/docs/Order.md

@@ -0,0 +1,27 @@
+
+
+# Order
+
+## Properties
+
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+**id** | **Long** |  |  [optional]
+**petId** | **Long** |  |  [optional]
+**quantity** | **Integer** |  |  [optional]
+**shipDate** | [**OffsetDateTime**](OffsetDateTime.md) |  |  [optional]
+**status** | [**StatusEnum**](#StatusEnum) | Order Status |  [optional]
+**complete** | **Boolean** |  |  [optional]
+
+
+
+## Enum: StatusEnum
+
+Name | Value
+---- | -----
+PLACED | "placed"
+APPROVED | "approved"
+DELIVERED | "delivered"
+
+
+

spring-swagger-codegen/spring-openapi-generator-api-client/docs/Pet.md

@@ -0,0 +1,27 @@
+
+
+# Pet
+
+## Properties
+
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+**id** | **Long** |  |  [optional]
+**category** | [**Category**](Category.md) |  |  [optional]
+**name** | **String** |  | 
+**photoUrls** | **List<String>** |  | 
+**tags** | [**List<Tag>**](Tag.md) |  |  [optional]
+**status** | [**StatusEnum**](#StatusEnum) | pet status in the store |  [optional]
+
+
+
+## Enum: StatusEnum
+
+Name | Value
+---- | -----
+AVAILABLE | "available"
+PENDING | "pending"
+SOLD | "sold"
+
+
+

spring-swagger-codegen/spring-openapi-generator-api-client/docs/PetApi.md

@@ -0,0 +1,581 @@
+# PetApi
+
+All URIs are relative to *https://petstore.swagger.io/v2*
+
+Method | HTTP request | Description
+------------- | ------------- | -------------
+[**addPet**](PetApi.md#addPet) | **POST** /pet | Add a new pet to the store
+[**deletePet**](PetApi.md#deletePet) | **DELETE** /pet/{petId} | Deletes a pet
+[**findPetsByStatus**](PetApi.md#findPetsByStatus) | **GET** /pet/findByStatus | Finds Pets by status
+[**findPetsByTags**](PetApi.md#findPetsByTags) | **GET** /pet/findByTags | Finds Pets by tags
+[**getPetById**](PetApi.md#getPetById) | **GET** /pet/{petId} | Find pet by ID
+[**updatePet**](PetApi.md#updatePet) | **PUT** /pet | Update an existing pet
+[**updatePetWithForm**](PetApi.md#updatePetWithForm) | **POST** /pet/{petId} | Updates a pet in the store with form data
+[**uploadFile**](PetApi.md#uploadFile) | **POST** /pet/{petId}/uploadImage | uploads an image
+
+
+
+## addPet
+
+> addPet(body)
+
+Add a new pet to the store
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.auth.*;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.PetApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+        
+        // Configure OAuth2 access token for authorization: petstore_auth
+        OAuth petstore_auth = (OAuth) defaultClient.getAuthentication("petstore_auth");
+        petstore_auth.setAccessToken("YOUR ACCESS TOKEN");
+
+        PetApi apiInstance = new PetApi(defaultClient);
+        Pet body = new Pet(); // Pet | Pet object that needs to be added to the store
+        try {
+            apiInstance.addPet(body);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling PetApi#addPet");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **body** | [**Pet**](Pet.md)| Pet object that needs to be added to the store |
+
+### Return type
+
+null (empty response body)
+
+### Authorization
+
+[petstore_auth](../README.md#petstore_auth)
+
+### HTTP request headers
+
+- **Content-Type**: application/json, application/xml
+- **Accept**: Not defined
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **405** | Invalid input |  -  |
+
+
+## deletePet
+
+> deletePet(petId, apiKey)
+
+Deletes a pet
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.auth.*;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.PetApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+        
+        // Configure OAuth2 access token for authorization: petstore_auth
+        OAuth petstore_auth = (OAuth) defaultClient.getAuthentication("petstore_auth");
+        petstore_auth.setAccessToken("YOUR ACCESS TOKEN");
+
+        PetApi apiInstance = new PetApi(defaultClient);
+        Long petId = 56L; // Long | Pet id to delete
+        String apiKey = "apiKey_example"; // String | 
+        try {
+            apiInstance.deletePet(petId, apiKey);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling PetApi#deletePet");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **petId** | **Long**| Pet id to delete |
+ **apiKey** | **String**|  | [optional]
+
+### Return type
+
+null (empty response body)
+
+### Authorization
+
+[petstore_auth](../README.md#petstore_auth)
+
+### HTTP request headers
+
+- **Content-Type**: Not defined
+- **Accept**: Not defined
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **400** | Invalid ID supplied |  -  |
+| **404** | Pet not found |  -  |
+
+
+## findPetsByStatus
+
+> List<Pet> findPetsByStatus(status)
+
+Finds Pets by status
+
+Multiple status values can be provided with comma separated strings
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.auth.*;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.PetApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+        
+        // Configure OAuth2 access token for authorization: petstore_auth
+        OAuth petstore_auth = (OAuth) defaultClient.getAuthentication("petstore_auth");
+        petstore_auth.setAccessToken("YOUR ACCESS TOKEN");
+
+        PetApi apiInstance = new PetApi(defaultClient);
+        List<String> status = Arrays.asList("available"); // List<String> | Status values that need to be considered for filter
+        try {
+            List<Pet> result = apiInstance.findPetsByStatus(status);
+            System.out.println(result);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling PetApi#findPetsByStatus");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **status** | [**List&lt;String&gt;**](String.md)| Status values that need to be considered for filter | [enum: available, pending, sold]
+
+### Return type
+
+[**List&lt;Pet&gt;**](Pet.md)
+
+### Authorization
+
+[petstore_auth](../README.md#petstore_auth)
+
+### HTTP request headers
+
+- **Content-Type**: Not defined
+- **Accept**: application/json, application/xml
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **200** | successful operation |  -  |
+| **400** | Invalid status value |  -  |
+
+
+## findPetsByTags
+
+> List&lt;Pet&gt; findPetsByTags(tags)
+
+Finds Pets by tags
+
+Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.auth.*;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.PetApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+        
+        // Configure OAuth2 access token for authorization: petstore_auth
+        OAuth petstore_auth = (OAuth) defaultClient.getAuthentication("petstore_auth");
+        petstore_auth.setAccessToken("YOUR ACCESS TOKEN");
+
+        PetApi apiInstance = new PetApi(defaultClient);
+        List<String> tags = Arrays.asList(); // List<String> | Tags to filter by
+        try {
+            List<Pet> result = apiInstance.findPetsByTags(tags);
+            System.out.println(result);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling PetApi#findPetsByTags");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **tags** | [**List&lt;String&gt;**](String.md)| Tags to filter by |
+
+### Return type
+
+[**List&lt;Pet&gt;**](Pet.md)
+
+### Authorization
+
+[petstore_auth](../README.md#petstore_auth)
+
+### HTTP request headers
+
+- **Content-Type**: Not defined
+- **Accept**: application/json, application/xml
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **200** | successful operation |  -  |
+| **400** | Invalid tag value |  -  |
+
+
+## getPetById
+
+> Pet getPetById(petId)
+
+Find pet by ID
+
+Returns a single pet
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.auth.*;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.PetApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+        
+        // Configure API key authorization: api_key
+        ApiKeyAuth api_key = (ApiKeyAuth) defaultClient.getAuthentication("api_key");
+        api_key.setApiKey("YOUR API KEY");
+        // Uncomment the following line to set a prefix for the API key, e.g. "Token" (defaults to null)
+        //api_key.setApiKeyPrefix("Token");
+
+        PetApi apiInstance = new PetApi(defaultClient);
+        Long petId = 56L; // Long | ID of pet to return
+        try {
+            Pet result = apiInstance.getPetById(petId);
+            System.out.println(result);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling PetApi#getPetById");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **petId** | **Long**| ID of pet to return |
+
+### Return type
+
+[**Pet**](Pet.md)
+
+### Authorization
+
+[api_key](../README.md#api_key)
+
+### HTTP request headers
+
+- **Content-Type**: Not defined
+- **Accept**: application/json, application/xml
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **200** | successful operation |  -  |
+| **400** | Invalid ID supplied |  -  |
+| **404** | Pet not found |  -  |
+
+
+## updatePet
+
+> updatePet(body)
+
+Update an existing pet
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.auth.*;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.PetApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+        
+        // Configure OAuth2 access token for authorization: petstore_auth
+        OAuth petstore_auth = (OAuth) defaultClient.getAuthentication("petstore_auth");
+        petstore_auth.setAccessToken("YOUR ACCESS TOKEN");
+
+        PetApi apiInstance = new PetApi(defaultClient);
+        Pet body = new Pet(); // Pet | Pet object that needs to be added to the store
+        try {
+            apiInstance.updatePet(body);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling PetApi#updatePet");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **body** | [**Pet**](Pet.md)| Pet object that needs to be added to the store |
+
+### Return type
+
+null (empty response body)
+
+### Authorization
+
+[petstore_auth](../README.md#petstore_auth)
+
+### HTTP request headers
+
+- **Content-Type**: application/json, application/xml
+- **Accept**: Not defined
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **400** | Invalid ID supplied |  -  |
+| **404** | Pet not found |  -  |
+| **405** | Validation exception |  -  |
+
+
+## updatePetWithForm
+
+> updatePetWithForm(petId, name, status)
+
+Updates a pet in the store with form data
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.auth.*;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.PetApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+        
+        // Configure OAuth2 access token for authorization: petstore_auth
+        OAuth petstore_auth = (OAuth) defaultClient.getAuthentication("petstore_auth");
+        petstore_auth.setAccessToken("YOUR ACCESS TOKEN");
+
+        PetApi apiInstance = new PetApi(defaultClient);
+        Long petId = 56L; // Long | ID of pet that needs to be updated
+        String name = "name_example"; // String | Updated name of the pet
+        String status = "status_example"; // String | Updated status of the pet
+        try {
+            apiInstance.updatePetWithForm(petId, name, status);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling PetApi#updatePetWithForm");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **petId** | **Long**| ID of pet that needs to be updated |
+ **name** | **String**| Updated name of the pet | [optional]
+ **status** | **String**| Updated status of the pet | [optional]
+
+### Return type
+
+null (empty response body)
+
+### Authorization
+
+[petstore_auth](../README.md#petstore_auth)
+
+### HTTP request headers
+
+- **Content-Type**: application/x-www-form-urlencoded
+- **Accept**: Not defined
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **405** | Invalid input |  -  |
+
+
+## uploadFile
+
+> ModelApiResponse uploadFile(petId, additionalMetadata, file)
+
+uploads an image
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.auth.*;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.PetApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+        
+        // Configure OAuth2 access token for authorization: petstore_auth
+        OAuth petstore_auth = (OAuth) defaultClient.getAuthentication("petstore_auth");
+        petstore_auth.setAccessToken("YOUR ACCESS TOKEN");
+
+        PetApi apiInstance = new PetApi(defaultClient);
+        Long petId = 56L; // Long | ID of pet to update
+        String additionalMetadata = "additionalMetadata_example"; // String | Additional data to pass to server
+        File file = new File("/path/to/file"); // File | file to upload
+        try {
+            ModelApiResponse result = apiInstance.uploadFile(petId, additionalMetadata, file);
+            System.out.println(result);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling PetApi#uploadFile");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **petId** | **Long**| ID of pet to update |
+ **additionalMetadata** | **String**| Additional data to pass to server | [optional]
+ **file** | **File**| file to upload | [optional]
+
+### Return type
+
+[**ModelApiResponse**](ModelApiResponse.md)
+
+### Authorization
+
+[petstore_auth](../README.md#petstore_auth)
+
+### HTTP request headers
+
+- **Content-Type**: multipart/form-data
+- **Accept**: application/json
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **200** | successful operation |  -  |
+

spring-swagger-codegen/spring-openapi-generator-api-client/docs/StoreApi.md

@@ -0,0 +1,276 @@
+# StoreApi
+
+All URIs are relative to *https://petstore.swagger.io/v2*
+
+Method | HTTP request | Description
+------------- | ------------- | -------------
+[**deleteOrder**](StoreApi.md#deleteOrder) | **DELETE** /store/order/{orderId} | Delete purchase order by ID
+[**getInventory**](StoreApi.md#getInventory) | **GET** /store/inventory | Returns pet inventories by status
+[**getOrderById**](StoreApi.md#getOrderById) | **GET** /store/order/{orderId} | Find purchase order by ID
+[**placeOrder**](StoreApi.md#placeOrder) | **POST** /store/order | Place an order for a pet
+
+
+
+## deleteOrder
+
+> deleteOrder(orderId)
+
+Delete purchase order by ID
+
+For valid response try integer IDs with positive integer value. Negative or non-integer values will generate API errors
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.StoreApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+
+        StoreApi apiInstance = new StoreApi(defaultClient);
+        Long orderId = 56L; // Long | ID of the order that needs to be deleted
+        try {
+            apiInstance.deleteOrder(orderId);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling StoreApi#deleteOrder");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **orderId** | **Long**| ID of the order that needs to be deleted |
+
+### Return type
+
+null (empty response body)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+- **Content-Type**: Not defined
+- **Accept**: Not defined
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **400** | Invalid ID supplied |  -  |
+| **404** | Order not found |  -  |
+
+
+## getInventory
+
+> Map<String, Integer> getInventory()
+
+Returns pet inventories by status
+
+Returns a map of status codes to quantities
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.auth.*;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.StoreApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+        
+        // Configure API key authorization: api_key
+        ApiKeyAuth api_key = (ApiKeyAuth) defaultClient.getAuthentication("api_key");
+        api_key.setApiKey("YOUR API KEY");
+        // Uncomment the following line to set a prefix for the API key, e.g. "Token" (defaults to null)
+        //api_key.setApiKeyPrefix("Token");
+
+        StoreApi apiInstance = new StoreApi(defaultClient);
+        try {
+            Map<String, Integer> result = apiInstance.getInventory();
+            System.out.println(result);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling StoreApi#getInventory");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+This endpoint does not need any parameter.
+
+### Return type
+
+**Map&lt;String, Integer&gt;**
+
+### Authorization
+
+[api_key](../README.md#api_key)
+
+### HTTP request headers
+
+- **Content-Type**: Not defined
+- **Accept**: application/json
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **200** | successful operation |  -  |
+
+
+## getOrderById
+
+> Order getOrderById(orderId)
+
+Find purchase order by ID
+
+For valid response try integer IDs with value &gt;&#x3D; 1 and &lt;&#x3D; 10. Other values will generated exceptions
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.StoreApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+
+        StoreApi apiInstance = new StoreApi(defaultClient);
+        Long orderId = 56L; // Long | ID of pet that needs to be fetched
+        try {
+            Order result = apiInstance.getOrderById(orderId);
+            System.out.println(result);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling StoreApi#getOrderById");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **orderId** | **Long**| ID of pet that needs to be fetched |
+
+### Return type
+
+[**Order**](Order.md)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+- **Content-Type**: Not defined
+- **Accept**: application/json, application/xml
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **200** | successful operation |  -  |
+| **400** | Invalid ID supplied |  -  |
+| **404** | Order not found |  -  |
+
+
+## placeOrder
+
+> Order placeOrder(body)
+
+Place an order for a pet
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.StoreApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+
+        StoreApi apiInstance = new StoreApi(defaultClient);
+        Order body = new Order(); // Order | order placed for purchasing the pet
+        try {
+            Order result = apiInstance.placeOrder(body);
+            System.out.println(result);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling StoreApi#placeOrder");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **body** | [**Order**](Order.md)| order placed for purchasing the pet |
+
+### Return type
+
+[**Order**](Order.md)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+- **Content-Type**: application/json
+- **Accept**: application/json, application/xml
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **200** | successful operation |  -  |
+| **400** | Invalid Order |  -  |
+

spring-swagger-codegen/spring-openapi-generator-api-client/docs/Tag.md

@@ -0,0 +1,13 @@
+
+
+# Tag
+
+## Properties
+
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+**id** | **Long** |  |  [optional]
+**name** | **String** |  |  [optional]
+
+
+

spring-swagger-codegen/spring-openapi-generator-api-client/docs/User.md

@@ -0,0 +1,19 @@
+
+
+# User
+
+## Properties
+
+Name | Type | Description | Notes
+------------ | ------------- | ------------- | -------------
+**id** | **Long** |  |  [optional]
+**username** | **String** |  |  [optional]
+**firstName** | **String** |  |  [optional]
+**lastName** | **String** |  |  [optional]
+**email** | **String** |  |  [optional]
+**password** | **String** |  |  [optional]
+**phone** | **String** |  |  [optional]
+**userStatus** | **Integer** | User Status |  [optional]
+
+
+

spring-swagger-codegen/spring-openapi-generator-api-client/docs/UserApi.md

@@ -0,0 +1,525 @@
+# UserApi
+
+All URIs are relative to *https://petstore.swagger.io/v2*
+
+Method | HTTP request | Description
+------------- | ------------- | -------------
+[**createUser**](UserApi.md#createUser) | **POST** /user | Create user
+[**createUsersWithArrayInput**](UserApi.md#createUsersWithArrayInput) | **POST** /user/createWithArray | Creates list of users with given input array
+[**createUsersWithListInput**](UserApi.md#createUsersWithListInput) | **POST** /user/createWithList | Creates list of users with given input array
+[**deleteUser**](UserApi.md#deleteUser) | **DELETE** /user/{username} | Delete user
+[**getUserByName**](UserApi.md#getUserByName) | **GET** /user/{username} | Get user by user name
+[**loginUser**](UserApi.md#loginUser) | **GET** /user/login | Logs user into the system
+[**logoutUser**](UserApi.md#logoutUser) | **GET** /user/logout | Logs out current logged in user session
+[**updateUser**](UserApi.md#updateUser) | **PUT** /user/{username} | Updated user
+
+
+
+## createUser
+
+> createUser(body)
+
+Create user
+
+This can only be done by the logged in user.
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.UserApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+
+        UserApi apiInstance = new UserApi(defaultClient);
+        User body = new User(); // User | Created user object
+        try {
+            apiInstance.createUser(body);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling UserApi#createUser");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **body** | [**User**](User.md)| Created user object |
+
+### Return type
+
+null (empty response body)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+- **Content-Type**: application/json
+- **Accept**: Not defined
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **0** | successful operation |  -  |
+
+
+## createUsersWithArrayInput
+
+> createUsersWithArrayInput(body)
+
+Creates list of users with given input array
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.UserApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+
+        UserApi apiInstance = new UserApi(defaultClient);
+        List<User> body = Arrays.asList(); // List<User> | List of user object
+        try {
+            apiInstance.createUsersWithArrayInput(body);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling UserApi#createUsersWithArrayInput");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **body** | [**List&lt;User&gt;**](User.md)| List of user object |
+
+### Return type
+
+null (empty response body)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+- **Content-Type**: application/json
+- **Accept**: Not defined
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **0** | successful operation |  -  |
+
+
+## createUsersWithListInput
+
+> createUsersWithListInput(body)
+
+Creates list of users with given input array
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.UserApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+
+        UserApi apiInstance = new UserApi(defaultClient);
+        List<User> body = Arrays.asList(); // List<User> | List of user object
+        try {
+            apiInstance.createUsersWithListInput(body);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling UserApi#createUsersWithListInput");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **body** | [**List&lt;User&gt;**](User.md)| List of user object |
+
+### Return type
+
+null (empty response body)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+- **Content-Type**: application/json
+- **Accept**: Not defined
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **0** | successful operation |  -  |
+
+
+## deleteUser
+
+> deleteUser(username)
+
+Delete user
+
+This can only be done by the logged in user.
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.UserApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+
+        UserApi apiInstance = new UserApi(defaultClient);
+        String username = "username_example"; // String | The name that needs to be deleted
+        try {
+            apiInstance.deleteUser(username);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling UserApi#deleteUser");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **username** | **String**| The name that needs to be deleted |
+
+### Return type
+
+null (empty response body)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+- **Content-Type**: Not defined
+- **Accept**: Not defined
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **400** | Invalid username supplied |  -  |
+| **404** | User not found |  -  |
+
+
+## getUserByName
+
+> User getUserByName(username)
+
+Get user by user name
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.UserApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+
+        UserApi apiInstance = new UserApi(defaultClient);
+        String username = "username_example"; // String | The name that needs to be fetched. Use user1 for testing. 
+        try {
+            User result = apiInstance.getUserByName(username);
+            System.out.println(result);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling UserApi#getUserByName");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **username** | **String**| The name that needs to be fetched. Use user1 for testing.  |
+
+### Return type
+
+[**User**](User.md)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+- **Content-Type**: Not defined
+- **Accept**: application/json, application/xml
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **200** | successful operation |  -  |
+| **400** | Invalid username supplied |  -  |
+| **404** | User not found |  -  |
+
+
+## loginUser
+
+> String loginUser(username, password)
+
+Logs user into the system
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.UserApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+
+        UserApi apiInstance = new UserApi(defaultClient);
+        String username = "username_example"; // String | The user name for login
+        String password = "password_example"; // String | The password for login in clear text
+        try {
+            String result = apiInstance.loginUser(username, password);
+            System.out.println(result);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling UserApi#loginUser");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **username** | **String**| The user name for login |
+ **password** | **String**| The password for login in clear text |
+
+### Return type
+
+**String**
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+- **Content-Type**: Not defined
+- **Accept**: application/json, application/xml
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **200** | successful operation |  * X-Rate-Limit - calls per hour allowed by the user <br>  * X-Expires-After - date in UTC when token expires <br>  |
+| **400** | Invalid username/password supplied |  -  |
+
+
+## logoutUser
+
+> logoutUser()
+
+Logs out current logged in user session
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.UserApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+
+        UserApi apiInstance = new UserApi(defaultClient);
+        try {
+            apiInstance.logoutUser();
+        } catch (ApiException e) {
+            System.err.println("Exception when calling UserApi#logoutUser");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+This endpoint does not need any parameter.
+
+### Return type
+
+null (empty response body)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+- **Content-Type**: Not defined
+- **Accept**: Not defined
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **0** | successful operation |  -  |
+
+
+## updateUser
+
+> updateUser(username, body)
+
+Updated user
+
+This can only be done by the logged in user.
+
+### Example
+
+```java
+// Import classes:
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.invoker.ApiException;
+import com.baeldung.petstore.client.invoker.Configuration;
+import com.baeldung.petstore.client.invoker.models.*;
+import com.baeldung.petstore.client.api.UserApi;
+
+public class Example {
+    public static void main(String[] args) {
+        ApiClient defaultClient = Configuration.getDefaultApiClient();
+        defaultClient.setBasePath("https://petstore.swagger.io/v2");
+
+        UserApi apiInstance = new UserApi(defaultClient);
+        String username = "username_example"; // String | name that need to be updated
+        User body = new User(); // User | Updated user object
+        try {
+            apiInstance.updateUser(username, body);
+        } catch (ApiException e) {
+            System.err.println("Exception when calling UserApi#updateUser");
+            System.err.println("Status code: " + e.getCode());
+            System.err.println("Reason: " + e.getResponseBody());
+            System.err.println("Response headers: " + e.getResponseHeaders());
+            e.printStackTrace();
+        }
+    }
+}
+```
+
+### Parameters
+
+
+Name | Type | Description  | Notes
+------------- | ------------- | ------------- | -------------
+ **username** | **String**| name that need to be updated |
+ **body** | [**User**](User.md)| Updated user object |
+
+### Return type
+
+null (empty response body)
+
+### Authorization
+
+No authorization required
+
+### HTTP request headers
+
+- **Content-Type**: application/json
+- **Accept**: Not defined
+
+### HTTP response details
+| Status code | Description | Response headers |
+|-------------|-------------|------------------|
+| **400** | Invalid user supplied |  -  |
+| **404** | User not found |  -  |
+

spring-swagger-codegen/spring-openapi-generator-api-client/git_push.sh

@@ -0,0 +1,58 @@
+#!/bin/sh
+# ref: https://help.github.com/articles/adding-an-existing-project-to-github-using-the-command-line/
+#
+# Usage example: /bin/sh ./git_push.sh wing328 openapi-pestore-perl "minor update" "gitlab.com"
+
+git_user_id=$1
+git_repo_id=$2
+release_note=$3
+git_host=$4
+
+if [ "$git_host" = "" ]; then
+    git_host="github.com"
+    echo "[INFO] No command line input provided. Set \$git_host to $git_host"
+fi
+
+if [ "$git_user_id" = "" ]; then
+    git_user_id="GIT_USER_ID"
+    echo "[INFO] No command line input provided. Set \$git_user_id to $git_user_id"
+fi
+
+if [ "$git_repo_id" = "" ]; then
+    git_repo_id="GIT_REPO_ID"
+    echo "[INFO] No command line input provided. Set \$git_repo_id to $git_repo_id"
+fi
+
+if [ "$release_note" = "" ]; then
+    release_note="Minor update"
+    echo "[INFO] No command line input provided. Set \$release_note to $release_note"
+fi
+
+# Initialize the local directory as a Git repository
+git init
+
+# Adds the files in the local repository and stages them for commit.
+git add .
+
+# Commits the tracked changes and prepares them to be pushed to a remote repository.
+git commit -m "$release_note"
+
+# Sets the new remote
+git_remote=`git remote`
+if [ "$git_remote" = "" ]; then # git remote not defined
+
+    if [ "$GIT_TOKEN" = "" ]; then
+        echo "[INFO] \$GIT_TOKEN (environment variable) is not set. Using the git credential in your environment."
+        git remote add origin https://${git_host}/${git_user_id}/${git_repo_id}.git
+    else
+        git remote add origin https://${git_user_id}:${GIT_TOKEN}@${git_host}/${git_user_id}/${git_repo_id}.git
+    fi
+
+fi
+
+git pull origin master
+
+# Pushes (Forces) the changes in the local repository up to the remote repository
+echo "Git pushing to https://${git_host}/${git_user_id}/${git_repo_id}.git"
+git push origin master 2>&1 | grep -v 'To https'
+

spring-swagger-codegen/spring-openapi-generator-api-client/gradle.properties

@@ -0,0 +1,2 @@
+# Uncomment to build for Android
+#target = android

spring-swagger-codegen/spring-openapi-generator-api-client/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.0.1-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

spring-swagger-codegen/spring-openapi-generator-api-client/gradlew

@@ -0,0 +1,183 @@
+#!/usr/bin/env sh
+
+#
+# Copyright 2015 the original author or authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if [ "$cygwin" = "true" -o "$msys" = "true" ] ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=`expr $i + 1`
+    done
+    case $i in
+        0) set -- ;;
+        1) set -- "$args0" ;;
+        2) set -- "$args0" "$args1" ;;
+        3) set -- "$args0" "$args1" "$args2" ;;
+        4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=`save "$@"`
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+exec "$JAVACMD" "$@"

spring-swagger-codegen/spring-openapi-generator-api-client/gradlew.bat

@@ -0,0 +1,100 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

spring-swagger-codegen/spring-openapi-generator-api-client/pom.xml

@@ -0,0 +1,274 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.baeldung</groupId>
+    <artifactId>spring-openapi-generator-api-client</artifactId>
+    <packaging>jar</packaging>
+    <name>spring-openapi-generator-api-client</name>
+    <version>0.0.1-SNAPSHOT</version>
+    <url>https://github.com/openapitools/openapi-generator</url>
+    <description>OpenAPI Java</description>
+    <scm>
+        <connection>scm:git:git@github.com:openapitools/openapi-generator.git</connection>
+        <developerConnection>scm:git:git@github.com:openapitools/openapi-generator.git</developerConnection>
+        <url>https://github.com/openapitools/openapi-generator</url>
+    </scm>
+
+    <licenses>
+        <license>
+            <name>Unlicense</name>
+            <url>http://www.apache.org/licenses/LICENSE-2.0.html</url>
+            <distribution>repo</distribution>
+        </license>
+    </licenses>
+
+    <developers>
+        <developer>
+            <name>OpenAPI-Generator Contributors</name>
+            <email>team@openapitools.org</email>
+            <organization>OpenAPITools.org</organization>
+            <organizationUrl>http://openapitools.org</organizationUrl>
+        </developer>
+    </developers>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-enforcer-plugin</artifactId>
+                <version>3.0.0-M1</version>
+                <executions>
+                    <execution>
+                        <id>enforce-maven</id>
+                        <goals>
+                            <goal>enforce</goal>
+                        </goals>
+                        <configuration>
+                            <rules>
+                                <requireMavenVersion>
+                                    <version>2.2.0</version>
+                                </requireMavenVersion>
+                            </rules>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-surefire-plugin</artifactId>
+                <version>2.12</version>
+                <configuration>
+                    <systemProperties>
+                        <property>
+                            <name>loggerPath</name>
+                            <value>conf/log4j.properties</value>
+                        </property>
+                    </systemProperties>
+                    <argLine>-Xms512m -Xmx1500m</argLine>
+                    <parallel>methods</parallel>
+                    <forkMode>pertest</forkMode>
+                </configuration>
+            </plugin>
+            <plugin>
+                <artifactId>maven-dependency-plugin</artifactId>
+                <executions>
+                    <execution>
+                        <phase>package</phase>
+                        <goals>
+                            <goal>copy-dependencies</goal>
+                        </goals>
+                        <configuration>
+                            <outputDirectory>${project.build.directory}/lib</outputDirectory>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+
+            <!-- attach test jar -->
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-jar-plugin</artifactId>
+                <version>2.2</version>
+                <executions>
+                    <execution>
+                        <goals>
+                            <goal>jar</goal>
+                            <goal>test-jar</goal>
+                        </goals>
+                    </execution>
+                </executions>
+                <configuration>
+                </configuration>
+            </plugin>
+
+            <plugin>
+                <groupId>org.codehaus.mojo</groupId>
+                <artifactId>build-helper-maven-plugin</artifactId>
+                <version>1.10</version>
+                <executions>
+                    <execution>
+                        <id>add_sources</id>
+                        <phase>generate-sources</phase>
+                        <goals>
+                            <goal>add-source</goal>
+                        </goals>
+                        <configuration>
+                            <sources>
+                                <source>src/main/java</source>
+                            </sources>
+                        </configuration>
+                    </execution>
+                    <execution>
+                        <id>add_test_sources</id>
+                        <phase>generate-test-sources</phase>
+                        <goals>
+                            <goal>add-test-source</goal>
+                        </goals>
+                        <configuration>
+                            <sources>
+                                <source>src/test/java</source>
+                            </sources>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.6.1</version>
+                <configuration>
+                        <source>1.8</source>
+                        <target>1.8</target>
+                </configuration>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-javadoc-plugin</artifactId>
+                <version>2.10.4</version>
+                <executions>
+                    <execution>
+                        <id>attach-javadocs</id>
+                        <goals>
+                            <goal>jar</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-source-plugin</artifactId>
+                <version>2.2.1</version>
+                <executions>
+                    <execution>
+                        <id>attach-sources</id>
+                        <goals>
+                            <goal>jar-no-fork</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+
+    <profiles>
+        <profile>
+            <id>sign-artifacts</id>
+            <build>
+                <plugins>
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-gpg-plugin</artifactId>
+                        <version>1.5</version>
+                        <executions>
+                            <execution>
+                                <id>sign-artifacts</id>
+                                <phase>verify</phase>
+                                <goals>
+                                    <goal>sign</goal>
+                                </goals>
+                            </execution>
+                        </executions>
+                    </plugin>
+                </plugins>
+            </build>
+        </profile>
+    </profiles>
+
+    <dependencies>
+        <dependency>
+            <groupId>io.swagger</groupId>
+            <artifactId>swagger-annotations</artifactId>
+            <version>${swagger-annotations-version}</version>
+        </dependency>
+        
+        <!-- @Nullable annotation -->
+        <dependency>
+            <groupId>com.google.code.findbugs</groupId>
+            <artifactId>jsr305</artifactId>
+            <version>3.0.2</version>
+        </dependency>
+
+        <!-- HTTP client: Spring RestTemplate -->
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-web</artifactId>
+            <version>${spring-web-version}</version>
+        </dependency>
+
+        <!-- JSON processing: jackson -->
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-core</artifactId>
+            <version>${jackson-version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-annotations</artifactId>
+            <version>${jackson-version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+            <version>${jackson-databind-version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.jaxrs</groupId>
+            <artifactId>jackson-jaxrs-json-provider</artifactId>
+            <version>${jackson-version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.openapitools</groupId>
+            <artifactId>jackson-databind-nullable</artifactId>
+            <version>${jackson-databind-nullable-version}</version>
+        </dependency>
+            <dependency>
+                <groupId>com.fasterxml.jackson.datatype</groupId>
+                <artifactId>jackson-datatype-jsr310</artifactId>
+                <version>${jackson-version}</version>
+            </dependency>
+            <dependency>
+                <groupId>com.github.joschi.jackson</groupId>
+                <artifactId>jackson-datatype-threetenbp</artifactId>
+                <version>${jackson-threetenbp-version}</version>
+            </dependency>
+
+        <!-- test dependencies -->
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>${junit-version}</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <swagger-annotations-version>1.5.22</swagger-annotations-version>
+        <spring-web-version>4.3.9.RELEASE</spring-web-version>
+        <jackson-version>2.10.1</jackson-version>
+        <jackson-databind-version>2.10.1</jackson-databind-version>
+        <jackson-databind-nullable-version>0.2.1</jackson-databind-nullable-version>
+        <jackson-threetenbp-version>2.9.10</jackson-threetenbp-version>
+        <maven-plugin-version>1.0.0</maven-plugin-version>
+        <junit-version>4.13</junit-version>
+    </properties>
+</project>

spring-swagger-codegen/spring-openapi-generator-api-client/settings.gradle

@@ -0,0 +1 @@
+rootProject.name = "spring-openapi-generator-api-client"

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/AndroidManifest.xml

@@ -0,0 +1,3 @@
+<manifest package="com.baeldung.petstore.client.invoker" xmlns:android="http://schemas.android.com/apk/res/android">
+    <application />
+</manifest>

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/api/PetApi.java

@@ -0,0 +1,477 @@
+package com.baeldung.petstore.client.api;
+
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.model.ModelApiResponse;
+import com.baeldung.petstore.client.model.Pet;
+
+import java.io.File;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.core.ParameterizedTypeReference;
+import org.springframework.core.io.FileSystemResource;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Component;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.client.HttpClientErrorException;
+import org.springframework.web.client.RestClientException;
+
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+@Component("com.baeldung.petstore.client.api.PetApi")
+public class PetApi {
+    private ApiClient apiClient;
+
+    public PetApi() {
+        this(new ApiClient());
+    }
+
+    @Autowired
+    public PetApi(ApiClient apiClient) {
+        this.apiClient = apiClient;
+    }
+
+    public ApiClient getApiClient() {
+        return apiClient;
+    }
+
+    public void setApiClient(ApiClient apiClient) {
+        this.apiClient = apiClient;
+    }
+
+    /**
+     * Add a new pet to the store
+     *
+     * <p><b>405</b> - Invalid input
+     * @param body Pet object that needs to be added to the store (required)
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public void addPet(Pet body) throws RestClientException {
+        addPetWithHttpInfo(body);
+    }
+
+    /**
+     * Add a new pet to the store
+     *
+     * <p><b>405</b> - Invalid input
+     * @param body Pet object that needs to be added to the store (required)
+     * @return ResponseEntity&lt;Void&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Void> addPetWithHttpInfo(Pet body) throws RestClientException {
+        Object postBody = body;
+
+        // verify the required parameter 'body' is set
+        if (body == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'body' when calling addPet");
+        }
+
+        String path = apiClient.expandPath("/pet", Collections.<String, Object>emptyMap());
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = { };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = {
+            "application/json", "application/xml"
+        };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] { "petstore_auth" };
+
+        ParameterizedTypeReference<Void> returnType = new ParameterizedTypeReference<Void>() {};
+        return apiClient.invokeAPI(path, HttpMethod.POST, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Deletes a pet
+     *
+     * <p><b>400</b> - Invalid ID supplied
+     * <p><b>404</b> - Pet not found
+     * @param petId Pet id to delete (required)
+     * @param apiKey  (optional)
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public void deletePet(Long petId, String apiKey) throws RestClientException {
+        deletePetWithHttpInfo(petId, apiKey);
+    }
+
+    /**
+     * Deletes a pet
+     *
+     * <p><b>400</b> - Invalid ID supplied
+     * <p><b>404</b> - Pet not found
+     * @param petId Pet id to delete (required)
+     * @param apiKey  (optional)
+     * @return ResponseEntity&lt;Void&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Void> deletePetWithHttpInfo(Long petId, String apiKey) throws RestClientException {
+        Object postBody = null;
+
+        // verify the required parameter 'petId' is set
+        if (petId == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'petId' when calling deletePet");
+        }
+
+        // create path and map variables
+        final Map<String, Object> uriVariables = new HashMap<String, Object>();
+        uriVariables.put("petId", petId);
+        String path = apiClient.expandPath("/pet/{petId}", uriVariables);
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        if (apiKey != null)
+        headerParams.add("api_key", apiClient.parameterToString(apiKey));
+
+        final String[] accepts = { };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = { };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] { "petstore_auth" };
+
+        ParameterizedTypeReference<Void> returnType = new ParameterizedTypeReference<Void>() {};
+        return apiClient.invokeAPI(path, HttpMethod.DELETE, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Finds Pets by status
+     * Multiple status values can be provided with comma separated strings
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid status value
+     * @param status Status values that need to be considered for filter (required)
+     * @return List&lt;Pet&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public List<Pet> findPetsByStatus(List<String> status) throws RestClientException {
+        return findPetsByStatusWithHttpInfo(status).getBody();
+    }
+
+    /**
+     * Finds Pets by status
+     * Multiple status values can be provided with comma separated strings
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid status value
+     * @param status Status values that need to be considered for filter (required)
+     * @return ResponseEntity&lt;List&lt;Pet&gt;&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<List<Pet>> findPetsByStatusWithHttpInfo(List<String> status) throws RestClientException {
+        Object postBody = null;
+
+        // verify the required parameter 'status' is set
+        if (status == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'status' when calling findPetsByStatus");
+        }
+
+        String path = apiClient.expandPath("/pet/findByStatus", Collections.<String, Object>emptyMap());
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        queryParams.putAll(apiClient.parameterToMultiValueMap(ApiClient.CollectionFormat.valueOf("multi".toUpperCase(Locale.ROOT)), "status", status));
+
+        final String[] accepts = {
+            "application/json", "application/xml"
+        };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = { };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] { "petstore_auth" };
+
+        ParameterizedTypeReference<List<Pet>> returnType = new ParameterizedTypeReference<List<Pet>>() {};
+        return apiClient.invokeAPI(path, HttpMethod.GET, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Finds Pets by tags
+     * Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid tag value
+     * @param tags Tags to filter by (required)
+     * @return List&lt;Pet&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    @Deprecated
+    public List<Pet> findPetsByTags(List<String> tags) throws RestClientException {
+        return findPetsByTagsWithHttpInfo(tags).getBody();
+    }
+
+    /**
+     * Finds Pets by tags
+     * Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid tag value
+     * @param tags Tags to filter by (required)
+     * @return ResponseEntity&lt;List&lt;Pet&gt;&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    @Deprecated
+    public ResponseEntity<List<Pet>> findPetsByTagsWithHttpInfo(List<String> tags) throws RestClientException {
+        Object postBody = null;
+
+        // verify the required parameter 'tags' is set
+        if (tags == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'tags' when calling findPetsByTags");
+        }
+
+        String path = apiClient.expandPath("/pet/findByTags", Collections.<String, Object>emptyMap());
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        queryParams.putAll(apiClient.parameterToMultiValueMap(ApiClient.CollectionFormat.valueOf("multi".toUpperCase(Locale.ROOT)), "tags", tags));
+
+        final String[] accepts = {
+            "application/json", "application/xml"
+        };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = { };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] { "petstore_auth" };
+
+        ParameterizedTypeReference<List<Pet>> returnType = new ParameterizedTypeReference<List<Pet>>() {};
+        return apiClient.invokeAPI(path, HttpMethod.GET, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Find pet by ID
+     * Returns a single pet
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid ID supplied
+     * <p><b>404</b> - Pet not found
+     * @param petId ID of pet to return (required)
+     * @return Pet
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public Pet getPetById(Long petId) throws RestClientException {
+        return getPetByIdWithHttpInfo(petId).getBody();
+    }
+
+    /**
+     * Find pet by ID
+     * Returns a single pet
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid ID supplied
+     * <p><b>404</b> - Pet not found
+     * @param petId ID of pet to return (required)
+     * @return ResponseEntity&lt;Pet&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Pet> getPetByIdWithHttpInfo(Long petId) throws RestClientException {
+        Object postBody = null;
+
+        // verify the required parameter 'petId' is set
+        if (petId == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'petId' when calling getPetById");
+        }
+
+        // create path and map variables
+        final Map<String, Object> uriVariables = new HashMap<String, Object>();
+        uriVariables.put("petId", petId);
+        String path = apiClient.expandPath("/pet/{petId}", uriVariables);
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = {
+            "application/json", "application/xml"
+        };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = { };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] { "api_key" };
+
+        ParameterizedTypeReference<Pet> returnType = new ParameterizedTypeReference<Pet>() {};
+        return apiClient.invokeAPI(path, HttpMethod.GET, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Update an existing pet
+     *
+     * <p><b>400</b> - Invalid ID supplied
+     * <p><b>404</b> - Pet not found
+     * <p><b>405</b> - Validation exception
+     * @param body Pet object that needs to be added to the store (required)
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public void updatePet(Pet body) throws RestClientException {
+        updatePetWithHttpInfo(body);
+    }
+
+    /**
+     * Update an existing pet
+     *
+     * <p><b>400</b> - Invalid ID supplied
+     * <p><b>404</b> - Pet not found
+     * <p><b>405</b> - Validation exception
+     * @param body Pet object that needs to be added to the store (required)
+     * @return ResponseEntity&lt;Void&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Void> updatePetWithHttpInfo(Pet body) throws RestClientException {
+        Object postBody = body;
+
+        // verify the required parameter 'body' is set
+        if (body == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'body' when calling updatePet");
+        }
+
+        String path = apiClient.expandPath("/pet", Collections.<String, Object>emptyMap());
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = { };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = {
+            "application/json", "application/xml"
+        };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] { "petstore_auth" };
+
+        ParameterizedTypeReference<Void> returnType = new ParameterizedTypeReference<Void>() {};
+        return apiClient.invokeAPI(path, HttpMethod.PUT, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Updates a pet in the store with form data
+     *
+     * <p><b>405</b> - Invalid input
+     * @param petId ID of pet that needs to be updated (required)
+     * @param name Updated name of the pet (optional)
+     * @param status Updated status of the pet (optional)
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public void updatePetWithForm(Long petId, String name, String status) throws RestClientException {
+        updatePetWithFormWithHttpInfo(petId, name, status);
+    }
+
+    /**
+     * Updates a pet in the store with form data
+     *
+     * <p><b>405</b> - Invalid input
+     * @param petId ID of pet that needs to be updated (required)
+     * @param name Updated name of the pet (optional)
+     * @param status Updated status of the pet (optional)
+     * @return ResponseEntity&lt;Void&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Void> updatePetWithFormWithHttpInfo(Long petId, String name, String status) throws RestClientException {
+        Object postBody = null;
+
+        // verify the required parameter 'petId' is set
+        if (petId == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'petId' when calling updatePetWithForm");
+        }
+
+        // create path and map variables
+        final Map<String, Object> uriVariables = new HashMap<String, Object>();
+        uriVariables.put("petId", petId);
+        String path = apiClient.expandPath("/pet/{petId}", uriVariables);
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        if (name != null)
+            formParams.add("name", name);
+        if (status != null)
+            formParams.add("status", status);
+
+        final String[] accepts = { };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = {
+            "application/x-www-form-urlencoded"
+        };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] { "petstore_auth" };
+
+        ParameterizedTypeReference<Void> returnType = new ParameterizedTypeReference<Void>() {};
+        return apiClient.invokeAPI(path, HttpMethod.POST, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * uploads an image
+     *
+     * <p><b>200</b> - successful operation
+     * @param petId ID of pet to update (required)
+     * @param additionalMetadata Additional data to pass to server (optional)
+     * @param file file to upload (optional)
+     * @return ModelApiResponse
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ModelApiResponse uploadFile(Long petId, String additionalMetadata, File file) throws RestClientException {
+        return uploadFileWithHttpInfo(petId, additionalMetadata, file).getBody();
+    }
+
+    /**
+     * uploads an image
+     *
+     * <p><b>200</b> - successful operation
+     * @param petId ID of pet to update (required)
+     * @param additionalMetadata Additional data to pass to server (optional)
+     * @param file file to upload (optional)
+     * @return ResponseEntity&lt;ModelApiResponse&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<ModelApiResponse> uploadFileWithHttpInfo(Long petId, String additionalMetadata, File file) throws RestClientException {
+        Object postBody = null;
+
+        // verify the required parameter 'petId' is set
+        if (petId == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'petId' when calling uploadFile");
+        }
+
+        // create path and map variables
+        final Map<String, Object> uriVariables = new HashMap<String, Object>();
+        uriVariables.put("petId", petId);
+        String path = apiClient.expandPath("/pet/{petId}/uploadImage", uriVariables);
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        if (additionalMetadata != null)
+            formParams.add("additionalMetadata", additionalMetadata);
+        if (file != null)
+            formParams.add("file", new FileSystemResource(file));
+
+        final String[] accepts = {
+            "application/json"
+        };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = {
+            "multipart/form-data"
+        };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] { "petstore_auth" };
+
+        ParameterizedTypeReference<ModelApiResponse> returnType = new ParameterizedTypeReference<ModelApiResponse>() {};
+        return apiClient.invokeAPI(path, HttpMethod.POST, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/api/StoreApi.java

@@ -0,0 +1,240 @@
+package com.baeldung.petstore.client.api;
+
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.model.Order;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.core.ParameterizedTypeReference;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Component;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.client.HttpClientErrorException;
+import org.springframework.web.client.RestClientException;
+
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+@Component("com.baeldung.petstore.client.api.StoreApi")
+public class StoreApi {
+    private ApiClient apiClient;
+
+    public StoreApi() {
+        this(new ApiClient());
+    }
+
+    @Autowired
+    public StoreApi(ApiClient apiClient) {
+        this.apiClient = apiClient;
+    }
+
+    public ApiClient getApiClient() {
+        return apiClient;
+    }
+
+    public void setApiClient(ApiClient apiClient) {
+        this.apiClient = apiClient;
+    }
+
+    /**
+     * Delete purchase order by ID
+     * For valid response try integer IDs with positive integer value. Negative or non-integer values will generate API errors
+     * <p><b>400</b> - Invalid ID supplied
+     * <p><b>404</b> - Order not found
+     * @param orderId ID of the order that needs to be deleted (required)
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public void deleteOrder(Long orderId) throws RestClientException {
+        deleteOrderWithHttpInfo(orderId);
+    }
+
+    /**
+     * Delete purchase order by ID
+     * For valid response try integer IDs with positive integer value. Negative or non-integer values will generate API errors
+     * <p><b>400</b> - Invalid ID supplied
+     * <p><b>404</b> - Order not found
+     * @param orderId ID of the order that needs to be deleted (required)
+     * @return ResponseEntity&lt;Void&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Void> deleteOrderWithHttpInfo(Long orderId) throws RestClientException {
+        Object postBody = null;
+
+        // verify the required parameter 'orderId' is set
+        if (orderId == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'orderId' when calling deleteOrder");
+        }
+
+        // create path and map variables
+        final Map<String, Object> uriVariables = new HashMap<String, Object>();
+        uriVariables.put("orderId", orderId);
+        String path = apiClient.expandPath("/store/order/{orderId}", uriVariables);
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = { };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = { };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] {  };
+
+        ParameterizedTypeReference<Void> returnType = new ParameterizedTypeReference<Void>() {};
+        return apiClient.invokeAPI(path, HttpMethod.DELETE, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Returns pet inventories by status
+     * Returns a map of status codes to quantities
+     * <p><b>200</b> - successful operation
+     * @return Map&lt;String, Integer&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public Map<String, Integer> getInventory() throws RestClientException {
+        return getInventoryWithHttpInfo().getBody();
+    }
+
+    /**
+     * Returns pet inventories by status
+     * Returns a map of status codes to quantities
+     * <p><b>200</b> - successful operation
+     * @return ResponseEntity&lt;Map&lt;String, Integer&gt;&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Map<String, Integer>> getInventoryWithHttpInfo() throws RestClientException {
+        Object postBody = null;
+
+        String path = apiClient.expandPath("/store/inventory", Collections.<String, Object>emptyMap());
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = {
+            "application/json"
+        };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = { };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] { "api_key" };
+
+        ParameterizedTypeReference<Map<String, Integer>> returnType = new ParameterizedTypeReference<Map<String, Integer>>() {};
+        return apiClient.invokeAPI(path, HttpMethod.GET, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Find purchase order by ID
+     * For valid response try integer IDs with value &gt;&#x3D; 1 and &lt;&#x3D; 10. Other values will generated exceptions
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid ID supplied
+     * <p><b>404</b> - Order not found
+     * @param orderId ID of pet that needs to be fetched (required)
+     * @return Order
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public Order getOrderById(Long orderId) throws RestClientException {
+        return getOrderByIdWithHttpInfo(orderId).getBody();
+    }
+
+    /**
+     * Find purchase order by ID
+     * For valid response try integer IDs with value &gt;&#x3D; 1 and &lt;&#x3D; 10. Other values will generated exceptions
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid ID supplied
+     * <p><b>404</b> - Order not found
+     * @param orderId ID of pet that needs to be fetched (required)
+     * @return ResponseEntity&lt;Order&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Order> getOrderByIdWithHttpInfo(Long orderId) throws RestClientException {
+        Object postBody = null;
+
+        // verify the required parameter 'orderId' is set
+        if (orderId == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'orderId' when calling getOrderById");
+        }
+
+        // create path and map variables
+        final Map<String, Object> uriVariables = new HashMap<String, Object>();
+        uriVariables.put("orderId", orderId);
+        String path = apiClient.expandPath("/store/order/{orderId}", uriVariables);
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = {
+            "application/json", "application/xml"
+        };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = { };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] {  };
+
+        ParameterizedTypeReference<Order> returnType = new ParameterizedTypeReference<Order>() {};
+        return apiClient.invokeAPI(path, HttpMethod.GET, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Place an order for a pet
+     *
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid Order
+     * @param body order placed for purchasing the pet (required)
+     * @return Order
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public Order placeOrder(Order body) throws RestClientException {
+        return placeOrderWithHttpInfo(body).getBody();
+    }
+
+    /**
+     * Place an order for a pet
+     *
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid Order
+     * @param body order placed for purchasing the pet (required)
+     * @return ResponseEntity&lt;Order&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Order> placeOrderWithHttpInfo(Order body) throws RestClientException {
+        Object postBody = body;
+
+        // verify the required parameter 'body' is set
+        if (body == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'body' when calling placeOrder");
+        }
+
+        String path = apiClient.expandPath("/store/order", Collections.<String, Object>emptyMap());
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = {
+            "application/json", "application/xml"
+        };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = {
+            "application/json"
+        };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] {  };
+
+        ParameterizedTypeReference<Order> returnType = new ParameterizedTypeReference<Order>() {};
+        return apiClient.invokeAPI(path, HttpMethod.POST, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/api/UserApi.java

@@ -0,0 +1,441 @@
+package com.baeldung.petstore.client.api;
+
+import com.baeldung.petstore.client.invoker.ApiClient;
+import com.baeldung.petstore.client.model.User;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.core.ParameterizedTypeReference;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Component;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.web.client.HttpClientErrorException;
+import org.springframework.web.client.RestClientException;
+
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+@Component("com.baeldung.petstore.client.api.UserApi")
+public class UserApi {
+    private ApiClient apiClient;
+
+    public UserApi() {
+        this(new ApiClient());
+    }
+
+    @Autowired
+    public UserApi(ApiClient apiClient) {
+        this.apiClient = apiClient;
+    }
+
+    public ApiClient getApiClient() {
+        return apiClient;
+    }
+
+    public void setApiClient(ApiClient apiClient) {
+        this.apiClient = apiClient;
+    }
+
+    /**
+     * Create user
+     * This can only be done by the logged in user.
+     * <p><b>0</b> - successful operation
+     * @param body Created user object (required)
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public void createUser(User body) throws RestClientException {
+        createUserWithHttpInfo(body);
+    }
+
+    /**
+     * Create user
+     * This can only be done by the logged in user.
+     * <p><b>0</b> - successful operation
+     * @param body Created user object (required)
+     * @return ResponseEntity&lt;Void&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Void> createUserWithHttpInfo(User body) throws RestClientException {
+        Object postBody = body;
+
+        // verify the required parameter 'body' is set
+        if (body == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'body' when calling createUser");
+        }
+
+        String path = apiClient.expandPath("/user", Collections.<String, Object>emptyMap());
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = { };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = {
+            "application/json"
+        };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] {  };
+
+        ParameterizedTypeReference<Void> returnType = new ParameterizedTypeReference<Void>() {};
+        return apiClient.invokeAPI(path, HttpMethod.POST, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Creates list of users with given input array
+     *
+     * <p><b>0</b> - successful operation
+     * @param body List of user object (required)
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public void createUsersWithArrayInput(List<User> body) throws RestClientException {
+        createUsersWithArrayInputWithHttpInfo(body);
+    }
+
+    /**
+     * Creates list of users with given input array
+     *
+     * <p><b>0</b> - successful operation
+     * @param body List of user object (required)
+     * @return ResponseEntity&lt;Void&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Void> createUsersWithArrayInputWithHttpInfo(List<User> body) throws RestClientException {
+        Object postBody = body;
+
+        // verify the required parameter 'body' is set
+        if (body == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'body' when calling createUsersWithArrayInput");
+        }
+
+        String path = apiClient.expandPath("/user/createWithArray", Collections.<String, Object>emptyMap());
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = { };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = {
+            "application/json"
+        };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] {  };
+
+        ParameterizedTypeReference<Void> returnType = new ParameterizedTypeReference<Void>() {};
+        return apiClient.invokeAPI(path, HttpMethod.POST, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Creates list of users with given input array
+     *
+     * <p><b>0</b> - successful operation
+     * @param body List of user object (required)
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public void createUsersWithListInput(List<User> body) throws RestClientException {
+        createUsersWithListInputWithHttpInfo(body);
+    }
+
+    /**
+     * Creates list of users with given input array
+     *
+     * <p><b>0</b> - successful operation
+     * @param body List of user object (required)
+     * @return ResponseEntity&lt;Void&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Void> createUsersWithListInputWithHttpInfo(List<User> body) throws RestClientException {
+        Object postBody = body;
+
+        // verify the required parameter 'body' is set
+        if (body == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'body' when calling createUsersWithListInput");
+        }
+
+        String path = apiClient.expandPath("/user/createWithList", Collections.<String, Object>emptyMap());
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = { };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = {
+            "application/json"
+        };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] {  };
+
+        ParameterizedTypeReference<Void> returnType = new ParameterizedTypeReference<Void>() {};
+        return apiClient.invokeAPI(path, HttpMethod.POST, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Delete user
+     * This can only be done by the logged in user.
+     * <p><b>400</b> - Invalid username supplied
+     * <p><b>404</b> - User not found
+     * @param username The name that needs to be deleted (required)
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public void deleteUser(String username) throws RestClientException {
+        deleteUserWithHttpInfo(username);
+    }
+
+    /**
+     * Delete user
+     * This can only be done by the logged in user.
+     * <p><b>400</b> - Invalid username supplied
+     * <p><b>404</b> - User not found
+     * @param username The name that needs to be deleted (required)
+     * @return ResponseEntity&lt;Void&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Void> deleteUserWithHttpInfo(String username) throws RestClientException {
+        Object postBody = null;
+
+        // verify the required parameter 'username' is set
+        if (username == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'username' when calling deleteUser");
+        }
+
+        // create path and map variables
+        final Map<String, Object> uriVariables = new HashMap<String, Object>();
+        uriVariables.put("username", username);
+        String path = apiClient.expandPath("/user/{username}", uriVariables);
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = { };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = { };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] {  };
+
+        ParameterizedTypeReference<Void> returnType = new ParameterizedTypeReference<Void>() {};
+        return apiClient.invokeAPI(path, HttpMethod.DELETE, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Get user by user name
+     *
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid username supplied
+     * <p><b>404</b> - User not found
+     * @param username The name that needs to be fetched. Use user1 for testing.  (required)
+     * @return User
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public User getUserByName(String username) throws RestClientException {
+        return getUserByNameWithHttpInfo(username).getBody();
+    }
+
+    /**
+     * Get user by user name
+     *
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid username supplied
+     * <p><b>404</b> - User not found
+     * @param username The name that needs to be fetched. Use user1 for testing.  (required)
+     * @return ResponseEntity&lt;User&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<User> getUserByNameWithHttpInfo(String username) throws RestClientException {
+        Object postBody = null;
+
+        // verify the required parameter 'username' is set
+        if (username == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'username' when calling getUserByName");
+        }
+
+        // create path and map variables
+        final Map<String, Object> uriVariables = new HashMap<String, Object>();
+        uriVariables.put("username", username);
+        String path = apiClient.expandPath("/user/{username}", uriVariables);
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = {
+            "application/json", "application/xml"
+        };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = { };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] {  };
+
+        ParameterizedTypeReference<User> returnType = new ParameterizedTypeReference<User>() {};
+        return apiClient.invokeAPI(path, HttpMethod.GET, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Logs user into the system
+     *
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid username/password supplied
+     * @param username The user name for login (required)
+     * @param password The password for login in clear text (required)
+     * @return String
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public String loginUser(String username, String password) throws RestClientException {
+        return loginUserWithHttpInfo(username, password).getBody();
+    }
+
+    /**
+     * Logs user into the system
+     *
+     * <p><b>200</b> - successful operation
+     * <p><b>400</b> - Invalid username/password supplied
+     * @param username The user name for login (required)
+     * @param password The password for login in clear text (required)
+     * @return ResponseEntity&lt;String&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<String> loginUserWithHttpInfo(String username, String password) throws RestClientException {
+        Object postBody = null;
+
+        // verify the required parameter 'username' is set
+        if (username == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'username' when calling loginUser");
+        }
+
+        // verify the required parameter 'password' is set
+        if (password == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'password' when calling loginUser");
+        }
+
+        String path = apiClient.expandPath("/user/login", Collections.<String, Object>emptyMap());
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        queryParams.putAll(apiClient.parameterToMultiValueMap(null, "username", username));
+        queryParams.putAll(apiClient.parameterToMultiValueMap(null, "password", password));
+
+        final String[] accepts = {
+            "application/json", "application/xml"
+        };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = { };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] {  };
+
+        ParameterizedTypeReference<String> returnType = new ParameterizedTypeReference<String>() {};
+        return apiClient.invokeAPI(path, HttpMethod.GET, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Logs out current logged in user session
+     *
+     * <p><b>0</b> - successful operation
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public void logoutUser() throws RestClientException {
+        logoutUserWithHttpInfo();
+    }
+
+    /**
+     * Logs out current logged in user session
+     *
+     * <p><b>0</b> - successful operation
+     * @return ResponseEntity&lt;Void&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Void> logoutUserWithHttpInfo() throws RestClientException {
+        Object postBody = null;
+
+        String path = apiClient.expandPath("/user/logout", Collections.<String, Object>emptyMap());
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = { };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = { };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] {  };
+
+        ParameterizedTypeReference<Void> returnType = new ParameterizedTypeReference<Void>() {};
+        return apiClient.invokeAPI(path, HttpMethod.GET, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+    /**
+     * Updated user
+     * This can only be done by the logged in user.
+     * <p><b>400</b> - Invalid user supplied
+     * <p><b>404</b> - User not found
+     * @param username name that need to be updated (required)
+     * @param body Updated user object (required)
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public void updateUser(String username, User body) throws RestClientException {
+        updateUserWithHttpInfo(username, body);
+    }
+
+    /**
+     * Updated user
+     * This can only be done by the logged in user.
+     * <p><b>400</b> - Invalid user supplied
+     * <p><b>404</b> - User not found
+     * @param username name that need to be updated (required)
+     * @param body Updated user object (required)
+     * @return ResponseEntity&lt;Void&gt;
+     * @throws RestClientException if an error occurs while attempting to invoke the API
+     */
+    public ResponseEntity<Void> updateUserWithHttpInfo(String username, User body) throws RestClientException {
+        Object postBody = body;
+
+        // verify the required parameter 'username' is set
+        if (username == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'username' when calling updateUser");
+        }
+
+        // verify the required parameter 'body' is set
+        if (body == null) {
+            throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'body' when calling updateUser");
+        }
+
+        // create path and map variables
+        final Map<String, Object> uriVariables = new HashMap<String, Object>();
+        uriVariables.put("username", username);
+        String path = apiClient.expandPath("/user/{username}", uriVariables);
+
+        final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>();
+        final HttpHeaders headerParams = new HttpHeaders();
+        final MultiValueMap<String, String> cookieParams = new LinkedMultiValueMap<String, String>();
+        final MultiValueMap formParams = new LinkedMultiValueMap();
+
+        final String[] accepts = { };
+        final List<MediaType> accept = apiClient.selectHeaderAccept(accepts);
+        final String[] contentTypes = {
+            "application/json"
+        };
+        final MediaType contentType = apiClient.selectHeaderContentType(contentTypes);
+
+        String[] authNames = new String[] {  };
+
+        ParameterizedTypeReference<Void> returnType = new ParameterizedTypeReference<Void>() {};
+        return apiClient.invokeAPI(path, HttpMethod.PUT, queryParams, postBody, headerParams, cookieParams, formParams, accept, contentType, authNames, returnType);
+    }
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/invoker/ApiClient.java

@@ -0,0 +1,750 @@
+package com.baeldung.petstore.client.invoker;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.datatype.threetenbp.ThreeTenModule;
+
+import com.baeldung.petstore.client.invoker.auth.ApiKeyAuth;
+import com.baeldung.petstore.client.invoker.auth.Authentication;
+import com.baeldung.petstore.client.invoker.auth.HttpBasicAuth;
+import com.baeldung.petstore.client.invoker.auth.HttpBearerAuth;
+import com.baeldung.petstore.client.invoker.auth.OAuth;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.UnsupportedEncodingException;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.net.URLEncoder;
+import java.nio.charset.StandardCharsets;
+import java.text.DateFormat;
+import java.text.ParseException;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.TimeZone;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.openapitools.jackson.nullable.JsonNullableModule;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.core.ParameterizedTypeReference;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpRequest;
+import org.springframework.http.InvalidMediaTypeException;
+import org.springframework.http.MediaType;
+import org.springframework.http.RequestEntity;
+import org.springframework.http.RequestEntity.BodyBuilder;
+import org.springframework.http.ResponseEntity;
+import org.springframework.http.client.BufferingClientHttpRequestFactory;
+import org.springframework.http.client.ClientHttpRequestExecution;
+import org.springframework.http.client.ClientHttpRequestInterceptor;
+import org.springframework.http.client.ClientHttpResponse;
+import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter;
+import org.springframework.stereotype.Component;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
+import org.springframework.util.StringUtils;
+import org.springframework.web.client.RestClientException;
+import org.springframework.web.client.RestTemplate;
+import org.springframework.web.util.UriComponentsBuilder;
+import org.threeten.bp.*;
+
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+@Component("com.baeldung.petstore.client.invoker.ApiClient")
+public class ApiClient {
+    public enum CollectionFormat {
+        CSV(","), TSV("\t"), SSV(" "), PIPES("|"), MULTI(null);
+
+        private final String separator;
+        private CollectionFormat(String separator) {
+            this.separator = separator;
+        }
+
+        private String collectionToString(Collection<?> collection) {
+            return StringUtils.collectionToDelimitedString(collection, separator);
+        }
+    }
+
+    private boolean debugging = false;
+
+    private HttpHeaders defaultHeaders = new HttpHeaders();
+    private MultiValueMap<String, String> defaultCookies = new LinkedMultiValueMap<String, String>();
+
+    private String basePath = "https://petstore.swagger.io/v2";
+
+    private RestTemplate restTemplate;
+
+    private Map<String, Authentication> authentications;
+
+    private DateFormat dateFormat;
+
+    public ApiClient() {
+        this.restTemplate = buildRestTemplate();
+        init();
+    }
+
+    @Autowired
+    public ApiClient(RestTemplate restTemplate) {
+        this.restTemplate = restTemplate;
+        init();
+    }
+
+    protected void init() {
+        // Use RFC3339 format for date and datetime.
+        // See http://xml2rfc.ietf.org/public/rfc/html/rfc3339.html#anchor14
+        this.dateFormat = new RFC3339DateFormat();
+
+        // Use UTC as the default time zone.
+        this.dateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
+
+        // Set default User-Agent.
+        setUserAgent("Java-SDK");
+
+        // Setup authentications (key: authentication name, value: authentication).
+        authentications = new HashMap<String, Authentication>();
+        authentications.put("api_key", new ApiKeyAuth("header", "api_key"));
+        authentications.put("petstore_auth", new OAuth());
+        // Prevent the authentications from being modified.
+        authentications = Collections.unmodifiableMap(authentications);
+    }
+
+    /**
+     * Get the current base path
+     * @return String the base path
+     */
+    public String getBasePath() {
+        return basePath;
+    }
+
+    /**
+     * Set the base path, which should include the host
+     * @param basePath the base path
+     * @return ApiClient this client
+     */
+    public ApiClient setBasePath(String basePath) {
+        this.basePath = basePath;
+        return this;
+    }
+
+    /**
+     * Get authentications (key: authentication name, value: authentication).
+     * @return Map the currently configured authentication types
+     */
+    public Map<String, Authentication> getAuthentications() {
+        return authentications;
+    }
+
+    /**
+     * Get authentication for the given name.
+     *
+     * @param authName The authentication name
+     * @return The authentication, null if not found
+     */
+    public Authentication getAuthentication(String authName) {
+        return authentications.get(authName);
+    }
+
+    /**
+     * Helper method to set token for HTTP bearer authentication.
+     * @param bearerToken the token
+     */
+    public void setBearerToken(String bearerToken) {
+      for (Authentication auth : authentications.values()) {
+        if (auth instanceof HttpBearerAuth) {
+          ((HttpBearerAuth) auth).setBearerToken(bearerToken);
+          return;
+        }
+      }
+      throw new RuntimeException("No Bearer authentication configured!");
+    }
+
+    /**
+     * Helper method to set username for the first HTTP basic authentication.
+     * @param username the username
+     */
+    public void setUsername(String username) {
+        for (Authentication auth : authentications.values()) {
+            if (auth instanceof HttpBasicAuth) {
+                ((HttpBasicAuth) auth).setUsername(username);
+                return;
+            }
+        }
+        throw new RuntimeException("No HTTP basic authentication configured!");
+    }
+
+    /**
+     * Helper method to set password for the first HTTP basic authentication.
+     * @param password the password
+     */
+    public void setPassword(String password) {
+        for (Authentication auth : authentications.values()) {
+            if (auth instanceof HttpBasicAuth) {
+                ((HttpBasicAuth) auth).setPassword(password);
+                return;
+            }
+        }
+        throw new RuntimeException("No HTTP basic authentication configured!");
+    }
+
+    /**
+     * Helper method to set API key value for the first API key authentication.
+     * @param apiKey the API key
+     */
+    public void setApiKey(String apiKey) {
+        for (Authentication auth : authentications.values()) {
+            if (auth instanceof ApiKeyAuth) {
+                ((ApiKeyAuth) auth).setApiKey(apiKey);
+                return;
+            }
+        }
+        throw new RuntimeException("No API key authentication configured!");
+    }
+
+    /**
+     * Helper method to set API key prefix for the first API key authentication.
+     * @param apiKeyPrefix the API key prefix
+     */
+    public void setApiKeyPrefix(String apiKeyPrefix) {
+        for (Authentication auth : authentications.values()) {
+            if (auth instanceof ApiKeyAuth) {
+                ((ApiKeyAuth) auth).setApiKeyPrefix(apiKeyPrefix);
+                return;
+            }
+        }
+        throw new RuntimeException("No API key authentication configured!");
+    }
+
+    /**
+     * Helper method to set access token for the first OAuth2 authentication.
+     * @param accessToken the access token
+     */
+    public void setAccessToken(String accessToken) {
+        for (Authentication auth : authentications.values()) {
+            if (auth instanceof OAuth) {
+                ((OAuth) auth).setAccessToken(accessToken);
+                return;
+            }
+        }
+        throw new RuntimeException("No OAuth2 authentication configured!");
+    }
+
+    /**
+     * Set the User-Agent header's value (by adding to the default header map).
+     * @param userAgent the user agent string
+     * @return ApiClient this client
+     */
+    public ApiClient setUserAgent(String userAgent) {
+        addDefaultHeader("User-Agent", userAgent);
+        return this;
+    }
+
+    /**
+     * Add a default header.
+     *
+     * @param name The header's name
+     * @param value The header's value
+     * @return ApiClient this client
+     */
+    public ApiClient addDefaultHeader(String name, String value) {
+        if (defaultHeaders.containsKey(name)) {
+            defaultHeaders.remove(name);
+        }
+        defaultHeaders.add(name, value);
+        return this;
+    }
+
+    /**
+     * Add a default cookie.
+     *
+     * @param name The cookie's name
+     * @param value The cookie's value
+     * @return ApiClient this client
+     */
+    public ApiClient addDefaultCookie(String name, String value) {
+        if (defaultCookies.containsKey(name)) {
+            defaultCookies.remove(name);
+        }
+        defaultCookies.add(name, value);
+        return this;
+    }
+
+    public void setDebugging(boolean debugging) {
+        List<ClientHttpRequestInterceptor> currentInterceptors = this.restTemplate.getInterceptors();
+        if(debugging) {
+            if (currentInterceptors == null) {
+                currentInterceptors = new ArrayList<ClientHttpRequestInterceptor>();
+            }
+            ClientHttpRequestInterceptor interceptor = new ApiClientHttpRequestInterceptor();
+            currentInterceptors.add(interceptor);
+            this.restTemplate.setInterceptors(currentInterceptors);
+        } else {
+            if (currentInterceptors != null && !currentInterceptors.isEmpty()) {
+                Iterator<ClientHttpRequestInterceptor> iter = currentInterceptors.iterator();
+                while (iter.hasNext()) {
+                    ClientHttpRequestInterceptor interceptor = iter.next();
+                    if (interceptor instanceof ApiClientHttpRequestInterceptor) {
+                        iter.remove();
+                    }
+                }
+                this.restTemplate.setInterceptors(currentInterceptors);
+            }
+        }
+        this.debugging = debugging;
+    }
+
+    /**
+     * Check that whether debugging is enabled for this API client.
+     * @return boolean true if this client is enabled for debugging, false otherwise
+     */
+    public boolean isDebugging() {
+        return debugging;
+    }
+
+    /**
+     * Get the date format used to parse/format date parameters.
+     * @return DateFormat format
+     */
+    public DateFormat getDateFormat() {
+        return dateFormat;
+    }
+
+    /**
+     * Set the date format used to parse/format date parameters.
+     * @param dateFormat Date format
+     * @return API client
+     */
+    public ApiClient setDateFormat(DateFormat dateFormat) {
+        this.dateFormat = dateFormat;
+        for(HttpMessageConverter converter:restTemplate.getMessageConverters()){
+            if(converter instanceof AbstractJackson2HttpMessageConverter){
+                ObjectMapper mapper = ((AbstractJackson2HttpMessageConverter)converter).getObjectMapper();
+                mapper.setDateFormat(dateFormat);
+            }
+        }
+        return this;
+    }
+
+    /**
+     * Parse the given string into Date object.
+     * @param str the string to parse
+     * @return the Date parsed from the string
+     */
+    public Date parseDate(String str) {
+        try {
+            return dateFormat.parse(str);
+        } catch (ParseException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    /**
+     * Format the given Date object into string.
+     * @param date the date to format
+     * @return the formatted date as string
+     */
+    public String formatDate(Date date) {
+        return dateFormat.format(date);
+    }
+
+    /**
+     * Format the given parameter object into string.
+     * @param param the object to convert
+     * @return String the parameter represented as a String
+     */
+    public String parameterToString(Object param) {
+        if (param == null) {
+            return "";
+        } else if (param instanceof Date) {
+            return formatDate( (Date) param);
+        } else if (param instanceof Collection) {
+            StringBuilder b = new StringBuilder();
+            for(Object o : (Collection<?>) param) {
+                if(b.length() > 0) {
+                    b.append(",");
+                }
+                b.append(String.valueOf(o));
+            }
+            return b.toString();
+        } else {
+            return String.valueOf(param);
+        }
+    }
+
+    /**
+    * Formats the specified collection path parameter to a string value.
+    *
+    * @param collectionFormat The collection format of the parameter.
+    * @param values The values of the parameter.
+    * @return String representation of the parameter
+    */
+    public String collectionPathParameterToString(CollectionFormat collectionFormat, Collection<?> values) {
+        // create the value based on the collection format
+        if (CollectionFormat.MULTI.equals(collectionFormat)) {
+            // not valid for path params
+            return parameterToString(values);
+        }
+
+        // collectionFormat is assumed to be "csv" by default
+        if(collectionFormat == null) {
+            collectionFormat = CollectionFormat.CSV;
+        }
+
+        return collectionFormat.collectionToString(values);
+    }
+
+    /**
+     * Converts a parameter to a {@link MultiValueMap} for use in REST requests
+     * @param collectionFormat The format to convert to
+     * @param name The name of the parameter
+     * @param value The parameter's value
+     * @return a Map containing the String value(s) of the input parameter
+     */
+    public MultiValueMap<String, String> parameterToMultiValueMap(CollectionFormat collectionFormat, String name, Object value) {
+        final MultiValueMap<String, String> params = new LinkedMultiValueMap<String, String>();
+
+        if (name == null || name.isEmpty() || value == null) {
+            return params;
+        }
+
+        if(collectionFormat == null) {
+            collectionFormat = CollectionFormat.CSV;
+        }
+
+        Collection<?> valueCollection = null;
+        if (value instanceof Collection) {
+            valueCollection = (Collection<?>) value;
+        } else {
+            params.add(name, parameterToString(value));
+            return params;
+        }
+
+        if (valueCollection.isEmpty()){
+            return params;
+        }
+
+        if (collectionFormat.equals(CollectionFormat.MULTI)) {
+            for (Object item : valueCollection) {
+                params.add(name, parameterToString(item));
+            }
+            return params;
+        }
+
+        List<String> values = new ArrayList<String>();
+        for(Object o : valueCollection) {
+            values.add(parameterToString(o));
+        }
+        params.add(name, collectionFormat.collectionToString(values));
+
+        return params;
+    }
+
+    /**
+    * Check if the given {@code String} is a JSON MIME.
+    * @param mediaType the input MediaType
+    * @return boolean true if the MediaType represents JSON, false otherwise
+    */
+    public boolean isJsonMime(String mediaType) {
+        // "* / *" is default to JSON
+        if ("*/*".equals(mediaType)) {
+            return true;
+        }
+
+        try {
+            return isJsonMime(MediaType.parseMediaType(mediaType));
+        } catch (InvalidMediaTypeException e) {
+        }
+        return false;
+    }
+
+    /**
+     * Check if the given MIME is a JSON MIME.
+     * JSON MIME examples:
+     *     application/json
+     *     application/json; charset=UTF8
+     *     APPLICATION/JSON
+     * @param mediaType the input MediaType
+     * @return boolean true if the MediaType represents JSON, false otherwise
+     */
+    public boolean isJsonMime(MediaType mediaType) {
+        return mediaType != null && (MediaType.APPLICATION_JSON.isCompatibleWith(mediaType) || mediaType.getSubtype().matches("^.*\\+json[;]?\\s*$"));
+    }
+
+    /**
+     * Select the Accept header's value from the given accepts array:
+     *     if JSON exists in the given array, use it;
+     *     otherwise use all of them (joining into a string)
+     *
+     * @param accepts The accepts array to select from
+     * @return List The list of MediaTypes to use for the Accept header
+     */
+    public List<MediaType> selectHeaderAccept(String[] accepts) {
+        if (accepts.length == 0) {
+            return null;
+        }
+        for (String accept : accepts) {
+            MediaType mediaType = MediaType.parseMediaType(accept);
+            if (isJsonMime(mediaType)) {
+                return Collections.singletonList(mediaType);
+            }
+        }
+        return MediaType.parseMediaTypes(StringUtils.arrayToCommaDelimitedString(accepts));
+    }
+
+    /**
+     * Select the Content-Type header's value from the given array:
+     *     if JSON exists in the given array, use it;
+     *     otherwise use the first one of the array.
+     *
+     * @param contentTypes The Content-Type array to select from
+     * @return MediaType The Content-Type header to use. If the given array is empty, JSON will be used.
+     */
+    public MediaType selectHeaderContentType(String[] contentTypes) {
+        if (contentTypes.length == 0) {
+            return MediaType.APPLICATION_JSON;
+        }
+        for (String contentType : contentTypes) {
+            MediaType mediaType = MediaType.parseMediaType(contentType);
+            if (isJsonMime(mediaType)) {
+                return mediaType;
+            }
+        }
+        return MediaType.parseMediaType(contentTypes[0]);
+    }
+
+    /**
+     * Select the body to use for the request
+     * @param obj the body object
+     * @param formParams the form parameters
+     * @param contentType the content type of the request
+     * @return Object the selected body
+     */
+    protected Object selectBody(Object obj, MultiValueMap<String, Object> formParams, MediaType contentType) {
+        boolean isForm = MediaType.MULTIPART_FORM_DATA.isCompatibleWith(contentType) || MediaType.APPLICATION_FORM_URLENCODED.isCompatibleWith(contentType);
+        return isForm ? formParams : obj;
+    }
+
+    /**
+     * Expand path template with variables
+     * @param pathTemplate path template with placeholders
+     * @param variables variables to replace
+     * @return path with placeholders replaced by variables
+     */
+    public String expandPath(String pathTemplate, Map<String, Object> variables) {
+        return restTemplate.getUriTemplateHandler().expand(pathTemplate, variables).toString();
+    }
+
+    /**
+     * Invoke API by sending HTTP request with the given options.
+     *
+     * @param <T> the return type to use
+     * @param path The sub-path of the HTTP URL
+     * @param method The request method
+     * @param queryParams The query parameters
+     * @param body The request body object
+     * @param headerParams The header parameters
+     * @param cookieParams The cookie parameters
+     * @param formParams The form parameters
+     * @param accept The request's Accept header
+     * @param contentType The request's Content-Type header
+     * @param authNames The authentications to apply
+     * @param returnType The return type into which to deserialize the response
+     * @return ResponseEntity&lt;T&gt; The response of the chosen type
+     */
+    public <T> ResponseEntity<T> invokeAPI(String path, HttpMethod method, MultiValueMap<String, String> queryParams, Object body, HttpHeaders headerParams, MultiValueMap<String, String> cookieParams, MultiValueMap<String, Object> formParams, List<MediaType> accept, MediaType contentType, String[] authNames, ParameterizedTypeReference<T> returnType) throws RestClientException {
+        updateParamsForAuth(authNames, queryParams, headerParams, cookieParams);
+
+        final UriComponentsBuilder builder = UriComponentsBuilder.fromHttpUrl(basePath).path(path);
+        if (queryParams != null) {
+            //encode the query parameters in case they contain unsafe characters
+            for (List<String> values : queryParams.values()) {
+                if (values != null) {
+                    for (int i = 0; i < values.size(); i++) {
+                        try {
+                            values.set(i, URLEncoder.encode(values.get(i), "utf8"));
+                        } catch (UnsupportedEncodingException e) {
+
+                        }
+                    }
+                }
+            }
+            builder.queryParams(queryParams);
+        }
+
+		URI uri;
+        try {
+            uri = new URI(builder.build().toUriString());
+        } catch(URISyntaxException ex)  {
+            throw new RestClientException("Could not build URL: " + builder.toUriString(), ex);
+        }
+
+        final BodyBuilder requestBuilder = RequestEntity.method(method, uri);
+        if(accept != null) {
+            requestBuilder.accept(accept.toArray(new MediaType[accept.size()]));
+        }
+        if(contentType != null) {
+            requestBuilder.contentType(contentType);
+        }
+
+        addHeadersToRequest(headerParams, requestBuilder);
+        addHeadersToRequest(defaultHeaders, requestBuilder);
+        addCookiesToRequest(cookieParams, requestBuilder);
+        addCookiesToRequest(defaultCookies, requestBuilder);
+
+        RequestEntity<Object> requestEntity = requestBuilder.body(selectBody(body, formParams, contentType));
+
+        ResponseEntity<T> responseEntity = restTemplate.exchange(requestEntity, returnType);
+
+        if (responseEntity.getStatusCode().is2xxSuccessful()) {
+            return responseEntity;
+        } else {
+            // The error handler built into the RestTemplate should handle 400 and 500 series errors.
+            throw new RestClientException("API returned " + responseEntity.getStatusCode() + " and it wasn't handled by the RestTemplate error handler");
+        }
+    }
+
+    /**
+     * Add headers to the request that is being built
+     * @param headers The headers to add
+     * @param requestBuilder The current request
+     */
+    protected void addHeadersToRequest(HttpHeaders headers, BodyBuilder requestBuilder) {
+        for (Entry<String, List<String>> entry : headers.entrySet()) {
+            List<String> values = entry.getValue();
+            for(String value : values) {
+                if (value != null) {
+                    requestBuilder.header(entry.getKey(), value);
+                }
+            }
+        }
+    }
+
+    /**
+     * Add cookies to the request that is being built
+     * @param cookies The cookies to add
+     * @param requestBuilder The current request
+     */
+    protected void addCookiesToRequest(MultiValueMap<String, String> cookies, BodyBuilder requestBuilder) {
+        if (!cookies.isEmpty()) {
+            requestBuilder.header("Cookie", buildCookieHeader(cookies));
+        }
+    }
+
+    /**
+     * Build cookie header. Keeps a single value per cookie (as per <a href="https://tools.ietf.org/html/rfc6265#section-5.3">
+     * RFC6265 section 5.3</a>).
+     *
+     * @param cookies map all cookies
+     * @return header string for cookies.
+     */
+    private String buildCookieHeader(MultiValueMap<String, String> cookies) {
+        final StringBuilder cookieValue = new StringBuilder();
+        String delimiter = "";
+        for (final Map.Entry<String, List<String>> entry : cookies.entrySet()) {
+            final String value = entry.getValue().get(entry.getValue().size() - 1);
+            cookieValue.append(String.format("%s%s=%s", delimiter, entry.getKey(), value));
+            delimiter = "; ";
+        }
+        return cookieValue.toString();
+    }
+
+    /**
+     * Build the RestTemplate used to make HTTP requests.
+     * @return RestTemplate
+     */
+    protected RestTemplate buildRestTemplate() {
+        RestTemplate restTemplate = new RestTemplate();
+        for(HttpMessageConverter converter:restTemplate.getMessageConverters()){
+            if(converter instanceof AbstractJackson2HttpMessageConverter){
+                ObjectMapper mapper = ((AbstractJackson2HttpMessageConverter)converter).getObjectMapper();
+                ThreeTenModule module = new ThreeTenModule();
+                module.addDeserializer(Instant.class, CustomInstantDeserializer.INSTANT);
+                module.addDeserializer(OffsetDateTime.class, CustomInstantDeserializer.OFFSET_DATE_TIME);
+                module.addDeserializer(ZonedDateTime.class, CustomInstantDeserializer.ZONED_DATE_TIME);
+                mapper.registerModule(module);
+                mapper.registerModule(new JsonNullableModule());
+            }
+        }
+        // This allows us to read the response more than once - Necessary for debugging.
+        restTemplate.setRequestFactory(new BufferingClientHttpRequestFactory(restTemplate.getRequestFactory()));
+        return restTemplate;
+    }
+
+    /**
+     * Update query and header parameters based on authentication settings.
+     *
+     * @param authNames The authentications to apply
+     * @param queryParams The query parameters
+     * @param headerParams The header parameters
+     */
+    private void updateParamsForAuth(String[] authNames, MultiValueMap<String, String> queryParams, HttpHeaders headerParams, MultiValueMap<String, String> cookieParams) {
+        for (String authName : authNames) {
+            Authentication auth = authentications.get(authName);
+            if (auth == null) {
+                throw new RestClientException("Authentication undefined: " + authName);
+            }
+            auth.applyToParams(queryParams, headerParams, cookieParams);
+        }
+    }
+
+    private class ApiClientHttpRequestInterceptor implements ClientHttpRequestInterceptor {
+        private final Log log = LogFactory.getLog(ApiClientHttpRequestInterceptor.class);
+
+        @Override
+        public ClientHttpResponse intercept(HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException {
+            logRequest(request, body);
+            ClientHttpResponse response = execution.execute(request, body);
+            logResponse(response);
+            return response;
+        }
+
+        private void logRequest(HttpRequest request, byte[] body) throws UnsupportedEncodingException {
+            log.info("URI: " + request.getURI());
+            log.info("HTTP Method: " + request.getMethod());
+            log.info("HTTP Headers: " + headersToString(request.getHeaders()));
+            log.info("Request Body: " + new String(body, StandardCharsets.UTF_8));
+        }
+
+        private void logResponse(ClientHttpResponse response) throws IOException {
+            log.info("HTTP Status Code: " + response.getRawStatusCode());
+            log.info("Status Text: " + response.getStatusText());
+            log.info("HTTP Headers: " + headersToString(response.getHeaders()));
+            log.info("Response Body: " + bodyToString(response.getBody()));
+        }
+
+        private String headersToString(HttpHeaders headers) {
+            StringBuilder builder = new StringBuilder();
+            for(Entry<String, List<String>> entry : headers.entrySet()) {
+                builder.append(entry.getKey()).append("=[");
+                for(String value : entry.getValue()) {
+                    builder.append(value).append(",");
+                }
+                builder.setLength(builder.length() - 1); // Get rid of trailing comma
+                builder.append("],");
+            }
+            builder.setLength(builder.length() - 1); // Get rid of trailing comma
+            return builder.toString();
+        }
+
+        private String bodyToString(InputStream body) throws IOException {
+            StringBuilder builder = new StringBuilder();
+            BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(body, StandardCharsets.UTF_8));
+            String line = bufferedReader.readLine();
+            while (line != null) {
+                builder.append(line).append(System.lineSeparator());
+                line = bufferedReader.readLine();
+            }
+            bufferedReader.close();
+            return builder.toString();
+        }
+    }
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/invoker/CustomInstantDeserializer.java

@@ -0,0 +1,233 @@
+package com.baeldung.petstore.client.invoker;
+
+import com.fasterxml.jackson.core.JsonParser;
+import com.fasterxml.jackson.core.JsonTokenId;
+import com.fasterxml.jackson.databind.DeserializationContext;
+import com.fasterxml.jackson.databind.DeserializationFeature;
+import com.fasterxml.jackson.databind.JsonDeserializer;
+import com.fasterxml.jackson.datatype.threetenbp.DecimalUtils;
+import com.fasterxml.jackson.datatype.threetenbp.deser.ThreeTenDateTimeDeserializerBase;
+import com.fasterxml.jackson.datatype.threetenbp.function.BiFunction;
+import com.fasterxml.jackson.datatype.threetenbp.function.Function;
+
+import java.io.IOException;
+import java.math.BigDecimal;
+
+import org.threeten.bp.DateTimeException;
+import org.threeten.bp.DateTimeUtils;
+import org.threeten.bp.Instant;
+import org.threeten.bp.OffsetDateTime;
+import org.threeten.bp.ZoneId;
+import org.threeten.bp.ZonedDateTime;
+import org.threeten.bp.format.DateTimeFormatter;
+import org.threeten.bp.temporal.Temporal;
+import org.threeten.bp.temporal.TemporalAccessor;
+
+/**
+ * Deserializer for ThreeTen temporal {@link Instant}s, {@link OffsetDateTime}, and {@link ZonedDateTime}s.
+ * Adapted from the jackson threetenbp InstantDeserializer to add support for deserializing rfc822 format.
+ *
+ * @author Nick Williams
+ */
+public class CustomInstantDeserializer<T extends Temporal>
+    extends ThreeTenDateTimeDeserializerBase<T> {
+  private static final long serialVersionUID = 1L;
+
+  public static final CustomInstantDeserializer<Instant> INSTANT = new CustomInstantDeserializer<Instant>(
+      Instant.class, DateTimeFormatter.ISO_INSTANT,
+      new Function<TemporalAccessor, Instant>() {
+        @Override
+        public Instant apply(TemporalAccessor temporalAccessor) {
+          return Instant.from(temporalAccessor);
+        }
+      },
+      new Function<FromIntegerArguments, Instant>() {
+        @Override
+        public Instant apply(FromIntegerArguments a) {
+          return Instant.ofEpochMilli(a.value);
+        }
+      },
+      new Function<FromDecimalArguments, Instant>() {
+        @Override
+        public Instant apply(FromDecimalArguments a) {
+          return Instant.ofEpochSecond(a.integer, a.fraction);
+        }
+      },
+      null
+  );
+
+  public static final CustomInstantDeserializer<OffsetDateTime> OFFSET_DATE_TIME = new CustomInstantDeserializer<OffsetDateTime>(
+      OffsetDateTime.class, DateTimeFormatter.ISO_OFFSET_DATE_TIME,
+      new Function<TemporalAccessor, OffsetDateTime>() {
+        @Override
+        public OffsetDateTime apply(TemporalAccessor temporalAccessor) {
+          return OffsetDateTime.from(temporalAccessor);
+        }
+      },
+      new Function<FromIntegerArguments, OffsetDateTime>() {
+        @Override
+        public OffsetDateTime apply(FromIntegerArguments a) {
+          return OffsetDateTime.ofInstant(Instant.ofEpochMilli(a.value), a.zoneId);
+        }
+      },
+      new Function<FromDecimalArguments, OffsetDateTime>() {
+        @Override
+        public OffsetDateTime apply(FromDecimalArguments a) {
+          return OffsetDateTime.ofInstant(Instant.ofEpochSecond(a.integer, a.fraction), a.zoneId);
+        }
+      },
+      new BiFunction<OffsetDateTime, ZoneId, OffsetDateTime>() {
+        @Override
+        public OffsetDateTime apply(OffsetDateTime d, ZoneId z) {
+          return d.withOffsetSameInstant(z.getRules().getOffset(d.toLocalDateTime()));
+        }
+      }
+  );
+
+  public static final CustomInstantDeserializer<ZonedDateTime> ZONED_DATE_TIME = new CustomInstantDeserializer<ZonedDateTime>(
+      ZonedDateTime.class, DateTimeFormatter.ISO_ZONED_DATE_TIME,
+      new Function<TemporalAccessor, ZonedDateTime>() {
+        @Override
+        public ZonedDateTime apply(TemporalAccessor temporalAccessor) {
+          return ZonedDateTime.from(temporalAccessor);
+        }
+      },
+      new Function<FromIntegerArguments, ZonedDateTime>() {
+        @Override
+        public ZonedDateTime apply(FromIntegerArguments a) {
+          return ZonedDateTime.ofInstant(Instant.ofEpochMilli(a.value), a.zoneId);
+        }
+      },
+      new Function<FromDecimalArguments, ZonedDateTime>() {
+        @Override
+        public ZonedDateTime apply(FromDecimalArguments a) {
+          return ZonedDateTime.ofInstant(Instant.ofEpochSecond(a.integer, a.fraction), a.zoneId);
+        }
+      },
+      new BiFunction<ZonedDateTime, ZoneId, ZonedDateTime>() {
+        @Override
+        public ZonedDateTime apply(ZonedDateTime zonedDateTime, ZoneId zoneId) {
+          return zonedDateTime.withZoneSameInstant(zoneId);
+        }
+      }
+  );
+
+  protected final Function<FromIntegerArguments, T> fromMilliseconds;
+
+  protected final Function<FromDecimalArguments, T> fromNanoseconds;
+
+  protected final Function<TemporalAccessor, T> parsedToValue;
+
+  protected final BiFunction<T, ZoneId, T> adjust;
+
+  protected CustomInstantDeserializer(Class<T> supportedType,
+                    DateTimeFormatter parser,
+                    Function<TemporalAccessor, T> parsedToValue,
+                    Function<FromIntegerArguments, T> fromMilliseconds,
+                    Function<FromDecimalArguments, T> fromNanoseconds,
+                    BiFunction<T, ZoneId, T> adjust) {
+    super(supportedType, parser);
+    this.parsedToValue = parsedToValue;
+    this.fromMilliseconds = fromMilliseconds;
+    this.fromNanoseconds = fromNanoseconds;
+    this.adjust = adjust == null ? new BiFunction<T, ZoneId, T>() {
+      @Override
+      public T apply(T t, ZoneId zoneId) {
+        return t;
+      }
+    } : adjust;
+  }
+
+  @SuppressWarnings("unchecked")
+  protected CustomInstantDeserializer(CustomInstantDeserializer<T> base, DateTimeFormatter f) {
+    super((Class<T>) base.handledType(), f);
+    parsedToValue = base.parsedToValue;
+    fromMilliseconds = base.fromMilliseconds;
+    fromNanoseconds = base.fromNanoseconds;
+    adjust = base.adjust;
+  }
+
+  @Override
+  protected JsonDeserializer<T> withDateFormat(DateTimeFormatter dtf) {
+    if (dtf == _formatter) {
+      return this;
+    }
+    return new CustomInstantDeserializer<T>(this, dtf);
+  }
+
+  @Override
+  public T deserialize(JsonParser parser, DeserializationContext context) throws IOException {
+    //NOTE: Timestamps contain no timezone info, and are always in configured TZ. Only
+    //string values have to be adjusted to the configured TZ.
+    switch (parser.getCurrentTokenId()) {
+      case JsonTokenId.ID_NUMBER_FLOAT: {
+        BigDecimal value = parser.getDecimalValue();
+        long seconds = value.longValue();
+        int nanoseconds = DecimalUtils.extractNanosecondDecimal(value, seconds);
+        return fromNanoseconds.apply(new FromDecimalArguments(
+            seconds, nanoseconds, getZone(context)));
+      }
+
+      case JsonTokenId.ID_NUMBER_INT: {
+        long timestamp = parser.getLongValue();
+        if (context.isEnabled(DeserializationFeature.READ_DATE_TIMESTAMPS_AS_NANOSECONDS)) {
+          return this.fromNanoseconds.apply(new FromDecimalArguments(
+              timestamp, 0, this.getZone(context)
+          ));
+        }
+        return this.fromMilliseconds.apply(new FromIntegerArguments(
+            timestamp, this.getZone(context)
+        ));
+      }
+
+      case JsonTokenId.ID_STRING: {
+        String string = parser.getText().trim();
+        if (string.length() == 0) {
+          return null;
+        }
+        if (string.endsWith("+0000")) {
+          string = string.substring(0, string.length() - 5) + "Z";
+        }
+        T value;
+        try {
+          TemporalAccessor acc = _formatter.parse(string);
+          value = parsedToValue.apply(acc);
+          if (context.isEnabled(DeserializationFeature.ADJUST_DATES_TO_CONTEXT_TIME_ZONE)) {
+            return adjust.apply(value, this.getZone(context));
+          }
+        } catch (DateTimeException e) {
+          throw _peelDTE(e);
+        }
+        return value;
+      }
+    }
+    throw context.mappingException("Expected type float, integer, or string.");
+  }
+
+  private ZoneId getZone(DeserializationContext context) {
+    // Instants are always in UTC, so don't waste compute cycles
+    return (_valueClass == Instant.class) ? null : DateTimeUtils.toZoneId(context.getTimeZone());
+  }
+
+  private static class FromIntegerArguments {
+    public final long value;
+    public final ZoneId zoneId;
+
+    private FromIntegerArguments(long value, ZoneId zoneId) {
+      this.value = value;
+      this.zoneId = zoneId;
+    }
+  }
+
+  private static class FromDecimalArguments {
+    public final long integer;
+    public final int fraction;
+    public final ZoneId zoneId;
+
+    private FromDecimalArguments(long integer, int fraction, ZoneId zoneId) {
+      this.integer = integer;
+      this.fraction = fraction;
+      this.zoneId = zoneId;
+    }
+  }
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/invoker/RFC3339DateFormat.java

@@ -0,0 +1,32 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+package com.baeldung.petstore.client.invoker;
+
+import com.fasterxml.jackson.databind.util.ISO8601DateFormat;
+import com.fasterxml.jackson.databind.util.ISO8601Utils;
+
+import java.text.FieldPosition;
+import java.util.Date;
+
+
+public class RFC3339DateFormat extends ISO8601DateFormat {
+
+  // Same as ISO8601DateFormat but serializing milliseconds.
+  @Override
+  public StringBuffer format(Date date, StringBuffer toAppendTo, FieldPosition fieldPosition) {
+    String value = ISO8601Utils.format(date, true);
+    toAppendTo.append(value);
+    return toAppendTo;
+  }
+
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/invoker/auth/ApiKeyAuth.java

@@ -0,0 +1,62 @@
+package com.baeldung.petstore.client.invoker.auth;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.util.MultiValueMap;
+
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+public class ApiKeyAuth implements Authentication {
+    private final String location;
+    private final String paramName;
+
+    private String apiKey;
+    private String apiKeyPrefix;
+
+    public ApiKeyAuth(String location, String paramName) {
+        this.location = location;
+        this.paramName = paramName;
+    }
+
+    public String getLocation() {
+        return location;
+    }
+
+    public String getParamName() {
+        return paramName;
+    }
+
+    public String getApiKey() {
+        return apiKey;
+    }
+
+    public void setApiKey(String apiKey) {
+        this.apiKey = apiKey;
+    }
+
+    public String getApiKeyPrefix() {
+        return apiKeyPrefix;
+    }
+
+    public void setApiKeyPrefix(String apiKeyPrefix) {
+        this.apiKeyPrefix = apiKeyPrefix;
+    }
+
+    @Override
+    public void applyToParams(MultiValueMap<String, String> queryParams, HttpHeaders headerParams, MultiValueMap<String, String> cookieParams) {
+        if (apiKey == null) {
+            return;
+        }
+        String value;
+        if (apiKeyPrefix != null) {
+            value = apiKeyPrefix + " " + apiKey;
+        } else {
+            value = apiKey;
+        }
+        if (location.equals("query")) {
+            queryParams.add(paramName, value);
+        } else if (location.equals("header")) {
+            headerParams.add(paramName, value);
+        } else if (location.equals("cookie")) {
+            cookieParams.add(paramName, value);
+        }
+    }
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/invoker/auth/Authentication.java

@@ -0,0 +1,14 @@
+package com.baeldung.petstore.client.invoker.auth;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.util.MultiValueMap;
+
+public interface Authentication {
+    /**
+     * Apply authentication settings to header and / or query parameters.
+     * @param queryParams The query parameters for the request
+     * @param headerParams The header parameters for the request
+     * @param cookieParams The cookie parameters for the request
+     */
+    public void applyToParams(MultiValueMap<String, String> queryParams, HttpHeaders headerParams, MultiValueMap<String, String> cookieParams);
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/invoker/auth/HttpBasicAuth.java

@@ -0,0 +1,38 @@
+package com.baeldung.petstore.client.invoker.auth;
+
+import java.nio.charset.StandardCharsets;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.util.Base64Utils;
+import org.springframework.util.MultiValueMap;
+
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+public class HttpBasicAuth implements Authentication {
+    private String username;
+    private String password;
+
+    public String getUsername() {
+        return username;
+    }
+
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    public String getPassword() {
+        return password;
+    }
+
+    public void setPassword(String password) {
+        this.password = password;
+    }
+
+    @Override
+    public void applyToParams(MultiValueMap<String, String> queryParams, HttpHeaders headerParams, MultiValueMap<String, String> cookieParams) {
+        if (username == null && password == null) {
+            return;
+        }
+        String str = (username == null ? "" : username) + ":" + (password == null ? "" : password);
+        headerParams.add(HttpHeaders.AUTHORIZATION, "Basic " + Base64Utils.encodeToString(str.getBytes(StandardCharsets.UTF_8)));
+    }
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/invoker/auth/HttpBearerAuth.java

@@ -0,0 +1,34 @@
+package com.baeldung.petstore.client.invoker.auth;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.util.MultiValueMap;
+
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+public class HttpBearerAuth implements Authentication {
+    private final String scheme;
+    private String bearerToken;
+
+    public HttpBearerAuth(String scheme) {
+        this.scheme = scheme;
+    }
+
+    public String getBearerToken() {
+        return bearerToken;
+    }
+
+    public void setBearerToken(String bearerToken) {
+        this.bearerToken = bearerToken;
+    }
+
+    @Override
+    public void applyToParams(MultiValueMap<String, String> queryParams, HttpHeaders headerParams, MultiValueMap<String, String> cookieParams) {
+        if (bearerToken == null) {
+            return;
+        }
+        headerParams.add(HttpHeaders.AUTHORIZATION, (scheme != null ? upperCaseBearer(scheme) + " " : "") + bearerToken);
+    }
+
+    private static String upperCaseBearer(String scheme) {
+        return ("bearer".equalsIgnoreCase(scheme)) ? "Bearer" : scheme;
+    }
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/invoker/auth/OAuth.java

@@ -0,0 +1,24 @@
+package com.baeldung.petstore.client.invoker.auth;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.util.MultiValueMap;
+
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+public class OAuth implements Authentication {
+    private String accessToken;
+
+    public String getAccessToken() {
+        return accessToken;
+    }
+
+    public void setAccessToken(String accessToken) {
+        this.accessToken = accessToken;
+    }
+
+    @Override
+    public void applyToParams(MultiValueMap<String, String> queryParams, HttpHeaders headerParams, MultiValueMap<String, String> cookieParams) {
+        if (accessToken != null) {
+            headerParams.add(HttpHeaders.AUTHORIZATION, "Bearer " + accessToken);
+        }
+    }
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/invoker/auth/OAuthFlow.java

@@ -0,0 +1,5 @@
+package com.baeldung.petstore.client.invoker.auth;
+
+public enum OAuthFlow {
+    accessCode, implicit, password, application
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/model/Category.java

@@ -0,0 +1,131 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.model;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+
+import java.util.Objects;
+
+import io.swagger.annotations.ApiModelProperty;
+
+/**
+ * Category
+ */
+@JsonPropertyOrder({
+  Category.JSON_PROPERTY_ID,
+  Category.JSON_PROPERTY_NAME
+})
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+public class Category {
+  public static final String JSON_PROPERTY_ID = "id";
+  private Long id;
+
+  public static final String JSON_PROPERTY_NAME = "name";
+  private String name;
+
+
+  public Category id(Long id) {
+
+    this.id = id;
+    return this;
+  }
+
+   /**
+   * Get id
+   * @return id
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_ID)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public Long getId() {
+    return id;
+  }
+
+
+  public void setId(Long id) {
+    this.id = id;
+  }
+
+
+  public Category name(String name) {
+
+    this.name = name;
+    return this;
+  }
+
+   /**
+   * Get name
+   * @return name
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_NAME)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public String getName() {
+    return name;
+  }
+
+
+  public void setName(String name) {
+    this.name = name;
+  }
+
+
+  @Override
+  public boolean equals(java.lang.Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+    Category category = (Category) o;
+    return Objects.equals(this.id, category.id) &&
+        Objects.equals(this.name, category.name);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(id, name);
+  }
+
+
+  @Override
+  public String toString() {
+    StringBuilder sb = new StringBuilder();
+    sb.append("class Category {\n");
+    sb.append("    id: ").append(toIndentedString(id)).append("\n");
+    sb.append("    name: ").append(toIndentedString(name)).append("\n");
+    sb.append("}");
+    return sb.toString();
+  }
+
+  /**
+   * Convert the given object to string with each line indented by 4 spaces
+   * (except the first line).
+   */
+  private String toIndentedString(java.lang.Object o) {
+    if (o == null) {
+      return "null";
+    }
+    return o.toString().replace("\n", "\n    ");
+  }
+
+}
+

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/model/ModelApiResponse.java

@@ -0,0 +1,162 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.model;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+
+import java.util.Objects;
+
+import io.swagger.annotations.ApiModelProperty;
+
+/**
+ * ModelApiResponse
+ */
+@JsonPropertyOrder({
+  ModelApiResponse.JSON_PROPERTY_CODE,
+  ModelApiResponse.JSON_PROPERTY_TYPE,
+  ModelApiResponse.JSON_PROPERTY_MESSAGE
+})
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+public class ModelApiResponse {
+  public static final String JSON_PROPERTY_CODE = "code";
+  private Integer code;
+
+  public static final String JSON_PROPERTY_TYPE = "type";
+  private String type;
+
+  public static final String JSON_PROPERTY_MESSAGE = "message";
+  private String message;
+
+
+  public ModelApiResponse code(Integer code) {
+
+    this.code = code;
+    return this;
+  }
+
+   /**
+   * Get code
+   * @return code
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_CODE)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public Integer getCode() {
+    return code;
+  }
+
+
+  public void setCode(Integer code) {
+    this.code = code;
+  }
+
+
+  public ModelApiResponse type(String type) {
+
+    this.type = type;
+    return this;
+  }
+
+   /**
+   * Get type
+   * @return type
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_TYPE)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public String getType() {
+    return type;
+  }
+
+
+  public void setType(String type) {
+    this.type = type;
+  }
+
+
+  public ModelApiResponse message(String message) {
+
+    this.message = message;
+    return this;
+  }
+
+   /**
+   * Get message
+   * @return message
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_MESSAGE)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public String getMessage() {
+    return message;
+  }
+
+
+  public void setMessage(String message) {
+    this.message = message;
+  }
+
+
+  @Override
+  public boolean equals(java.lang.Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+    ModelApiResponse _apiResponse = (ModelApiResponse) o;
+    return Objects.equals(this.code, _apiResponse.code) &&
+        Objects.equals(this.type, _apiResponse.type) &&
+        Objects.equals(this.message, _apiResponse.message);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(code, type, message);
+  }
+
+
+  @Override
+  public String toString() {
+    StringBuilder sb = new StringBuilder();
+    sb.append("class ModelApiResponse {\n");
+    sb.append("    code: ").append(toIndentedString(code)).append("\n");
+    sb.append("    type: ").append(toIndentedString(type)).append("\n");
+    sb.append("    message: ").append(toIndentedString(message)).append("\n");
+    sb.append("}");
+    return sb.toString();
+  }
+
+  /**
+   * Convert the given object to string with each line indented by 4 spaces
+   * (except the first line).
+   */
+  private String toIndentedString(java.lang.Object o) {
+    if (o == null) {
+      return "null";
+    }
+    return o.toString().replace("\n", "\n    ");
+  }
+
+}
+

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/model/Order.java

@@ -0,0 +1,296 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.model;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+import com.fasterxml.jackson.annotation.JsonValue;
+
+import java.util.Objects;
+
+import org.threeten.bp.OffsetDateTime;
+
+import io.swagger.annotations.ApiModelProperty;
+
+/**
+ * Order
+ */
+@JsonPropertyOrder({
+  Order.JSON_PROPERTY_ID,
+  Order.JSON_PROPERTY_PET_ID,
+  Order.JSON_PROPERTY_QUANTITY,
+  Order.JSON_PROPERTY_SHIP_DATE,
+  Order.JSON_PROPERTY_STATUS,
+  Order.JSON_PROPERTY_COMPLETE
+})
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+public class Order {
+  public static final String JSON_PROPERTY_ID = "id";
+  private Long id;
+
+  public static final String JSON_PROPERTY_PET_ID = "petId";
+  private Long petId;
+
+  public static final String JSON_PROPERTY_QUANTITY = "quantity";
+  private Integer quantity;
+
+  public static final String JSON_PROPERTY_SHIP_DATE = "shipDate";
+  private OffsetDateTime shipDate;
+
+  /**
+   * Order Status
+   */
+  public enum StatusEnum {
+    PLACED("placed"),
+
+    APPROVED("approved"),
+
+    DELIVERED("delivered");
+
+    private String value;
+
+    StatusEnum(String value) {
+      this.value = value;
+    }
+
+    @JsonValue
+    public String getValue() {
+      return value;
+    }
+
+    @Override
+    public String toString() {
+      return String.valueOf(value);
+    }
+
+    @JsonCreator
+    public static StatusEnum fromValue(String value) {
+      for (StatusEnum b : StatusEnum.values()) {
+        if (b.value.equals(value)) {
+          return b;
+        }
+      }
+      throw new IllegalArgumentException("Unexpected value '" + value + "'");
+    }
+  }
+
+  public static final String JSON_PROPERTY_STATUS = "status";
+  private StatusEnum status;
+
+  public static final String JSON_PROPERTY_COMPLETE = "complete";
+  private Boolean complete;
+
+
+  public Order id(Long id) {
+
+    this.id = id;
+    return this;
+  }
+
+   /**
+   * Get id
+   * @return id
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_ID)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public Long getId() {
+    return id;
+  }
+
+
+  public void setId(Long id) {
+    this.id = id;
+  }
+
+
+  public Order petId(Long petId) {
+
+    this.petId = petId;
+    return this;
+  }
+
+   /**
+   * Get petId
+   * @return petId
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_PET_ID)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public Long getPetId() {
+    return petId;
+  }
+
+
+  public void setPetId(Long petId) {
+    this.petId = petId;
+  }
+
+
+  public Order quantity(Integer quantity) {
+
+    this.quantity = quantity;
+    return this;
+  }
+
+   /**
+   * Get quantity
+   * @return quantity
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_QUANTITY)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public Integer getQuantity() {
+    return quantity;
+  }
+
+
+  public void setQuantity(Integer quantity) {
+    this.quantity = quantity;
+  }
+
+
+  public Order shipDate(OffsetDateTime shipDate) {
+
+    this.shipDate = shipDate;
+    return this;
+  }
+
+   /**
+   * Get shipDate
+   * @return shipDate
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_SHIP_DATE)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public OffsetDateTime getShipDate() {
+    return shipDate;
+  }
+
+
+  public void setShipDate(OffsetDateTime shipDate) {
+    this.shipDate = shipDate;
+  }
+
+
+  public Order status(StatusEnum status) {
+
+    this.status = status;
+    return this;
+  }
+
+   /**
+   * Order Status
+   * @return status
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "Order Status")
+  @JsonProperty(JSON_PROPERTY_STATUS)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public StatusEnum getStatus() {
+    return status;
+  }
+
+
+  public void setStatus(StatusEnum status) {
+    this.status = status;
+  }
+
+
+  public Order complete(Boolean complete) {
+
+    this.complete = complete;
+    return this;
+  }
+
+   /**
+   * Get complete
+   * @return complete
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_COMPLETE)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public Boolean getComplete() {
+    return complete;
+  }
+
+
+  public void setComplete(Boolean complete) {
+    this.complete = complete;
+  }
+
+
+  @Override
+  public boolean equals(java.lang.Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+    Order order = (Order) o;
+    return Objects.equals(this.id, order.id) &&
+        Objects.equals(this.petId, order.petId) &&
+        Objects.equals(this.quantity, order.quantity) &&
+        Objects.equals(this.shipDate, order.shipDate) &&
+        Objects.equals(this.status, order.status) &&
+        Objects.equals(this.complete, order.complete);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(id, petId, quantity, shipDate, status, complete);
+  }
+
+
+  @Override
+  public String toString() {
+    StringBuilder sb = new StringBuilder();
+    sb.append("class Order {\n");
+    sb.append("    id: ").append(toIndentedString(id)).append("\n");
+    sb.append("    petId: ").append(toIndentedString(petId)).append("\n");
+    sb.append("    quantity: ").append(toIndentedString(quantity)).append("\n");
+    sb.append("    shipDate: ").append(toIndentedString(shipDate)).append("\n");
+    sb.append("    status: ").append(toIndentedString(status)).append("\n");
+    sb.append("    complete: ").append(toIndentedString(complete)).append("\n");
+    sb.append("}");
+    return sb.toString();
+  }
+
+  /**
+   * Convert the given object to string with each line indented by 4 spaces
+   * (except the first line).
+   */
+  private String toIndentedString(java.lang.Object o) {
+    if (o == null) {
+      return "null";
+    }
+    return o.toString().replace("\n", "\n    ");
+  }
+
+}
+

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/model/Pet.java

@@ -0,0 +1,310 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.model;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+import com.fasterxml.jackson.annotation.JsonValue;
+
+import com.baeldung.petstore.client.model.Category;
+import com.baeldung.petstore.client.model.Tag;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+import io.swagger.annotations.ApiModelProperty;
+
+/**
+ * Pet
+ */
+@JsonPropertyOrder({
+  Pet.JSON_PROPERTY_ID,
+  Pet.JSON_PROPERTY_CATEGORY,
+  Pet.JSON_PROPERTY_NAME,
+  Pet.JSON_PROPERTY_PHOTO_URLS,
+  Pet.JSON_PROPERTY_TAGS,
+  Pet.JSON_PROPERTY_STATUS
+})
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+public class Pet {
+  public static final String JSON_PROPERTY_ID = "id";
+  private Long id;
+
+  public static final String JSON_PROPERTY_CATEGORY = "category";
+  private Category category;
+
+  public static final String JSON_PROPERTY_NAME = "name";
+  private String name;
+
+  public static final String JSON_PROPERTY_PHOTO_URLS = "photoUrls";
+  private List<String> photoUrls = new ArrayList<>();
+
+  public static final String JSON_PROPERTY_TAGS = "tags";
+  private List<Tag> tags = null;
+
+  /**
+   * pet status in the store
+   */
+  public enum StatusEnum {
+    AVAILABLE("available"),
+
+    PENDING("pending"),
+
+    SOLD("sold");
+
+    private String value;
+
+    StatusEnum(String value) {
+      this.value = value;
+    }
+
+    @JsonValue
+    public String getValue() {
+      return value;
+    }
+
+    @Override
+    public String toString() {
+      return String.valueOf(value);
+    }
+
+    @JsonCreator
+    public static StatusEnum fromValue(String value) {
+      for (StatusEnum b : StatusEnum.values()) {
+        if (b.value.equals(value)) {
+          return b;
+        }
+      }
+      throw new IllegalArgumentException("Unexpected value '" + value + "'");
+    }
+  }
+
+  public static final String JSON_PROPERTY_STATUS = "status";
+  private StatusEnum status;
+
+
+  public Pet id(Long id) {
+
+    this.id = id;
+    return this;
+  }
+
+   /**
+   * Get id
+   * @return id
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_ID)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public Long getId() {
+    return id;
+  }
+
+
+  public void setId(Long id) {
+    this.id = id;
+  }
+
+
+  public Pet category(Category category) {
+
+    this.category = category;
+    return this;
+  }
+
+   /**
+   * Get category
+   * @return category
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_CATEGORY)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public Category getCategory() {
+    return category;
+  }
+
+
+  public void setCategory(Category category) {
+    this.category = category;
+  }
+
+
+  public Pet name(String name) {
+
+    this.name = name;
+    return this;
+  }
+
+   /**
+   * Get name
+   * @return name
+  **/
+  @ApiModelProperty(example = "doggie", required = true, value = "")
+  @JsonProperty(JSON_PROPERTY_NAME)
+  @JsonInclude(value = JsonInclude.Include.ALWAYS)
+
+  public String getName() {
+    return name;
+  }
+
+
+  public void setName(String name) {
+    this.name = name;
+  }
+
+
+  public Pet photoUrls(List<String> photoUrls) {
+
+    this.photoUrls = photoUrls;
+    return this;
+  }
+
+  public Pet addPhotoUrlsItem(String photoUrlsItem) {
+    this.photoUrls.add(photoUrlsItem);
+    return this;
+  }
+
+   /**
+   * Get photoUrls
+   * @return photoUrls
+  **/
+  @ApiModelProperty(required = true, value = "")
+  @JsonProperty(JSON_PROPERTY_PHOTO_URLS)
+  @JsonInclude(value = JsonInclude.Include.ALWAYS)
+
+  public List<String> getPhotoUrls() {
+    return photoUrls;
+  }
+
+
+  public void setPhotoUrls(List<String> photoUrls) {
+    this.photoUrls = photoUrls;
+  }
+
+
+  public Pet tags(List<Tag> tags) {
+
+    this.tags = tags;
+    return this;
+  }
+
+  public Pet addTagsItem(Tag tagsItem) {
+    if (this.tags == null) {
+      this.tags = new ArrayList<>();
+    }
+    this.tags.add(tagsItem);
+    return this;
+  }
+
+   /**
+   * Get tags
+   * @return tags
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_TAGS)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public List<Tag> getTags() {
+    return tags;
+  }
+
+
+  public void setTags(List<Tag> tags) {
+    this.tags = tags;
+  }
+
+
+  public Pet status(StatusEnum status) {
+
+    this.status = status;
+    return this;
+  }
+
+   /**
+   * pet status in the store
+   * @return status
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "pet status in the store")
+  @JsonProperty(JSON_PROPERTY_STATUS)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public StatusEnum getStatus() {
+    return status;
+  }
+
+
+  public void setStatus(StatusEnum status) {
+    this.status = status;
+  }
+
+
+  @Override
+  public boolean equals(java.lang.Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+    Pet pet = (Pet) o;
+    return Objects.equals(this.id, pet.id) &&
+        Objects.equals(this.category, pet.category) &&
+        Objects.equals(this.name, pet.name) &&
+        Objects.equals(this.photoUrls, pet.photoUrls) &&
+        Objects.equals(this.tags, pet.tags) &&
+        Objects.equals(this.status, pet.status);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(id, category, name, photoUrls, tags, status);
+  }
+
+
+  @Override
+  public String toString() {
+    StringBuilder sb = new StringBuilder();
+    sb.append("class Pet {\n");
+    sb.append("    id: ").append(toIndentedString(id)).append("\n");
+    sb.append("    category: ").append(toIndentedString(category)).append("\n");
+    sb.append("    name: ").append(toIndentedString(name)).append("\n");
+    sb.append("    photoUrls: ").append(toIndentedString(photoUrls)).append("\n");
+    sb.append("    tags: ").append(toIndentedString(tags)).append("\n");
+    sb.append("    status: ").append(toIndentedString(status)).append("\n");
+    sb.append("}");
+    return sb.toString();
+  }
+
+  /**
+   * Convert the given object to string with each line indented by 4 spaces
+   * (except the first line).
+   */
+  private String toIndentedString(java.lang.Object o) {
+    if (o == null) {
+      return "null";
+    }
+    return o.toString().replace("\n", "\n    ");
+  }
+
+}
+

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/model/Tag.java

@@ -0,0 +1,131 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.model;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+
+import java.util.Objects;
+
+import io.swagger.annotations.ApiModelProperty;
+
+/**
+ * Tag
+ */
+@JsonPropertyOrder({
+  Tag.JSON_PROPERTY_ID,
+  Tag.JSON_PROPERTY_NAME
+})
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+public class Tag {
+  public static final String JSON_PROPERTY_ID = "id";
+  private Long id;
+
+  public static final String JSON_PROPERTY_NAME = "name";
+  private String name;
+
+
+  public Tag id(Long id) {
+
+    this.id = id;
+    return this;
+  }
+
+   /**
+   * Get id
+   * @return id
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_ID)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public Long getId() {
+    return id;
+  }
+
+
+  public void setId(Long id) {
+    this.id = id;
+  }
+
+
+  public Tag name(String name) {
+
+    this.name = name;
+    return this;
+  }
+
+   /**
+   * Get name
+   * @return name
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_NAME)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public String getName() {
+    return name;
+  }
+
+
+  public void setName(String name) {
+    this.name = name;
+  }
+
+
+  @Override
+  public boolean equals(java.lang.Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+    Tag tag = (Tag) o;
+    return Objects.equals(this.id, tag.id) &&
+        Objects.equals(this.name, tag.name);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(id, name);
+  }
+
+
+  @Override
+  public String toString() {
+    StringBuilder sb = new StringBuilder();
+    sb.append("class Tag {\n");
+    sb.append("    id: ").append(toIndentedString(id)).append("\n");
+    sb.append("    name: ").append(toIndentedString(name)).append("\n");
+    sb.append("}");
+    return sb.toString();
+  }
+
+  /**
+   * Convert the given object to string with each line indented by 4 spaces
+   * (except the first line).
+   */
+  private String toIndentedString(java.lang.Object o) {
+    if (o == null) {
+      return "null";
+    }
+    return o.toString().replace("\n", "\n    ");
+  }
+
+}
+

spring-swagger-codegen/spring-openapi-generator-api-client/src/main/java/com/baeldung/petstore/client/model/User.java

@@ -0,0 +1,317 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.model;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+
+import java.util.Objects;
+
+import io.swagger.annotations.ApiModelProperty;
+
+/**
+ * User
+ */
+@JsonPropertyOrder({
+  User.JSON_PROPERTY_ID,
+  User.JSON_PROPERTY_USERNAME,
+  User.JSON_PROPERTY_FIRST_NAME,
+  User.JSON_PROPERTY_LAST_NAME,
+  User.JSON_PROPERTY_EMAIL,
+  User.JSON_PROPERTY_PASSWORD,
+  User.JSON_PROPERTY_PHONE,
+  User.JSON_PROPERTY_USER_STATUS
+})
+@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2020-03-15T06:14:01.568992-05:00[America/Chicago]")
+public class User {
+  public static final String JSON_PROPERTY_ID = "id";
+  private Long id;
+
+  public static final String JSON_PROPERTY_USERNAME = "username";
+  private String username;
+
+  public static final String JSON_PROPERTY_FIRST_NAME = "firstName";
+  private String firstName;
+
+  public static final String JSON_PROPERTY_LAST_NAME = "lastName";
+  private String lastName;
+
+  public static final String JSON_PROPERTY_EMAIL = "email";
+  private String email;
+
+  public static final String JSON_PROPERTY_PASSWORD = "password";
+  private String password;
+
+  public static final String JSON_PROPERTY_PHONE = "phone";
+  private String phone;
+
+  public static final String JSON_PROPERTY_USER_STATUS = "userStatus";
+  private Integer userStatus;
+
+
+  public User id(Long id) {
+
+    this.id = id;
+    return this;
+  }
+
+   /**
+   * Get id
+   * @return id
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_ID)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public Long getId() {
+    return id;
+  }
+
+
+  public void setId(Long id) {
+    this.id = id;
+  }
+
+
+  public User username(String username) {
+
+    this.username = username;
+    return this;
+  }
+
+   /**
+   * Get username
+   * @return username
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_USERNAME)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public String getUsername() {
+    return username;
+  }
+
+
+  public void setUsername(String username) {
+    this.username = username;
+  }
+
+
+  public User firstName(String firstName) {
+
+    this.firstName = firstName;
+    return this;
+  }
+
+   /**
+   * Get firstName
+   * @return firstName
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_FIRST_NAME)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public String getFirstName() {
+    return firstName;
+  }
+
+
+  public void setFirstName(String firstName) {
+    this.firstName = firstName;
+  }
+
+
+  public User lastName(String lastName) {
+
+    this.lastName = lastName;
+    return this;
+  }
+
+   /**
+   * Get lastName
+   * @return lastName
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_LAST_NAME)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public String getLastName() {
+    return lastName;
+  }
+
+
+  public void setLastName(String lastName) {
+    this.lastName = lastName;
+  }
+
+
+  public User email(String email) {
+
+    this.email = email;
+    return this;
+  }
+
+   /**
+   * Get email
+   * @return email
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_EMAIL)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public String getEmail() {
+    return email;
+  }
+
+
+  public void setEmail(String email) {
+    this.email = email;
+  }
+
+
+  public User password(String password) {
+
+    this.password = password;
+    return this;
+  }
+
+   /**
+   * Get password
+   * @return password
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_PASSWORD)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public String getPassword() {
+    return password;
+  }
+
+
+  public void setPassword(String password) {
+    this.password = password;
+  }
+
+
+  public User phone(String phone) {
+
+    this.phone = phone;
+    return this;
+  }
+
+   /**
+   * Get phone
+   * @return phone
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "")
+  @JsonProperty(JSON_PROPERTY_PHONE)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public String getPhone() {
+    return phone;
+  }
+
+
+  public void setPhone(String phone) {
+    this.phone = phone;
+  }
+
+
+  public User userStatus(Integer userStatus) {
+
+    this.userStatus = userStatus;
+    return this;
+  }
+
+   /**
+   * User Status
+   * @return userStatus
+  **/
+  @javax.annotation.Nullable
+  @ApiModelProperty(value = "User Status")
+  @JsonProperty(JSON_PROPERTY_USER_STATUS)
+  @JsonInclude(value = JsonInclude.Include.USE_DEFAULTS)
+
+  public Integer getUserStatus() {
+    return userStatus;
+  }
+
+
+  public void setUserStatus(Integer userStatus) {
+    this.userStatus = userStatus;
+  }
+
+
+  @Override
+  public boolean equals(java.lang.Object o) {
+    if (this == o) {
+      return true;
+    }
+    if (o == null || getClass() != o.getClass()) {
+      return false;
+    }
+    User user = (User) o;
+    return Objects.equals(this.id, user.id) &&
+        Objects.equals(this.username, user.username) &&
+        Objects.equals(this.firstName, user.firstName) &&
+        Objects.equals(this.lastName, user.lastName) &&
+        Objects.equals(this.email, user.email) &&
+        Objects.equals(this.password, user.password) &&
+        Objects.equals(this.phone, user.phone) &&
+        Objects.equals(this.userStatus, user.userStatus);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(id, username, firstName, lastName, email, password, phone, userStatus);
+  }
+
+
+  @Override
+  public String toString() {
+    StringBuilder sb = new StringBuilder();
+    sb.append("class User {\n");
+    sb.append("    id: ").append(toIndentedString(id)).append("\n");
+    sb.append("    username: ").append(toIndentedString(username)).append("\n");
+    sb.append("    firstName: ").append(toIndentedString(firstName)).append("\n");
+    sb.append("    lastName: ").append(toIndentedString(lastName)).append("\n");
+    sb.append("    email: ").append(toIndentedString(email)).append("\n");
+    sb.append("    password: ").append(toIndentedString(password)).append("\n");
+    sb.append("    phone: ").append(toIndentedString(phone)).append("\n");
+    sb.append("    userStatus: ").append(toIndentedString(userStatus)).append("\n");
+    sb.append("}");
+    return sb.toString();
+  }
+
+  /**
+   * Convert the given object to string with each line indented by 4 spaces
+   * (except the first line).
+   */
+  private String toIndentedString(java.lang.Object o) {
+    if (o == null) {
+      return "null";
+    }
+    return o.toString().replace("\n", "\n    ");
+  }
+
+}
+

spring-swagger-codegen/spring-openapi-generator-api-client/src/test/java/com/baeldung/petstore/client/api/PetApiTest.java

@@ -0,0 +1,167 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.api;
+
+import com.baeldung.petstore.client.model.ModelApiResponse;
+import com.baeldung.petstore.client.model.Pet;
+
+import java.io.File;
+import java.util.List;
+
+import org.junit.Ignore;
+import org.junit.Test;
+
+/**
+ * API tests for PetApi
+ */
+@Ignore
+public class PetApiTest {
+
+    private final PetApi api = new PetApi();
+
+
+    /**
+     * Add a new pet to the store
+     *
+     *
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void addPetTest() {
+        Pet body = null;
+        api.addPet(body);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Deletes a pet
+     *
+     *
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void deletePetTest() {
+        Long petId = null;
+        String apiKey = null;
+        api.deletePet(petId, apiKey);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Finds Pets by status
+     *
+     * Multiple status values can be provided with comma separated strings
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void findPetsByStatusTest() {
+        List<String> status = null;
+        List<Pet> response = api.findPetsByStatus(status);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Finds Pets by tags
+     *
+     * Multiple tags can be provided with comma separated strings. Use tag1, tag2, tag3 for testing.
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void findPetsByTagsTest() {
+        List<String> tags = null;
+        List<Pet> response = api.findPetsByTags(tags);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Find pet by ID
+     *
+     * Returns a single pet
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void getPetByIdTest() {
+        Long petId = null;
+        Pet response = api.getPetById(petId);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Update an existing pet
+     *
+     *
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void updatePetTest() {
+        Pet body = null;
+        api.updatePet(body);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Updates a pet in the store with form data
+     *
+     *
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void updatePetWithFormTest() {
+        Long petId = null;
+        String name = null;
+        String status = null;
+        api.updatePetWithForm(petId, name, status);
+
+        // TODO: test validations
+    }
+
+    /**
+     * uploads an image
+     *
+     *
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void uploadFileTest() {
+        Long petId = null;
+        String additionalMetadata = null;
+        File file = null;
+        ModelApiResponse response = api.uploadFile(petId, additionalMetadata, file);
+
+        // TODO: test validations
+    }
+
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/test/java/com/baeldung/petstore/client/api/StoreApiTest.java

@@ -0,0 +1,95 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.api;
+
+import com.baeldung.petstore.client.model.Order;
+
+import java.util.Map;
+
+import org.junit.Ignore;
+import org.junit.Test;
+
+/**
+ * API tests for StoreApi
+ */
+@Ignore
+public class StoreApiTest {
+
+    private final StoreApi api = new StoreApi();
+
+
+    /**
+     * Delete purchase order by ID
+     *
+     * For valid response try integer IDs with positive integer value. Negative or non-integer values will generate API errors
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void deleteOrderTest() {
+        Long orderId = null;
+        api.deleteOrder(orderId);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Returns pet inventories by status
+     *
+     * Returns a map of status codes to quantities
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void getInventoryTest() {
+        Map<String, Integer> response = api.getInventory();
+
+        // TODO: test validations
+    }
+
+    /**
+     * Find purchase order by ID
+     *
+     * For valid response try integer IDs with value &gt;&#x3D; 1 and &lt;&#x3D; 10. Other values will generated exceptions
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void getOrderByIdTest() {
+        Long orderId = null;
+        Order response = api.getOrderById(orderId);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Place an order for a pet
+     *
+     *
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void placeOrderTest() {
+        Order body = null;
+        Order response = api.placeOrder(body);
+
+        // TODO: test validations
+    }
+
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/test/java/com/baeldung/petstore/client/api/UserApiTest.java

@@ -0,0 +1,161 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.api;
+
+import com.baeldung.petstore.client.model.User;
+
+import java.util.List;
+
+import org.junit.Ignore;
+import org.junit.Test;
+
+/**
+ * API tests for UserApi
+ */
+@Ignore
+public class UserApiTest {
+
+    private final UserApi api = new UserApi();
+
+
+    /**
+     * Create user
+     *
+     * This can only be done by the logged in user.
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void createUserTest() {
+        User body = null;
+        api.createUser(body);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Creates list of users with given input array
+     *
+     *
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void createUsersWithArrayInputTest() {
+        List<User> body = null;
+        api.createUsersWithArrayInput(body);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Creates list of users with given input array
+     *
+     *
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void createUsersWithListInputTest() {
+        List<User> body = null;
+        api.createUsersWithListInput(body);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Delete user
+     *
+     * This can only be done by the logged in user.
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void deleteUserTest() {
+        String username = null;
+        api.deleteUser(username);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Get user by user name
+     *
+     *
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void getUserByNameTest() {
+        String username = null;
+        User response = api.getUserByName(username);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Logs user into the system
+     *
+     *
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void loginUserTest() {
+        String username = null;
+        String password = null;
+        String response = api.loginUser(username, password);
+
+        // TODO: test validations
+    }
+
+    /**
+     * Logs out current logged in user session
+     *
+     *
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void logoutUserTest() {
+        api.logoutUser();
+
+        // TODO: test validations
+    }
+
+    /**
+     * Updated user
+     *
+     * This can only be done by the logged in user.
+     *
+     * @throws ApiException
+     *          if the Api call fails
+     */
+    @Test
+    public void updateUserTest() {
+        String username = null;
+        User body = null;
+        api.updateUser(username, body);
+
+        // TODO: test validations
+    }
+
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/test/java/com/baeldung/petstore/client/model/CategoryTest.java

@@ -0,0 +1,49 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.model;
+
+import org.junit.Test;
+
+
+/**
+ * Model tests for Category
+ */
+public class CategoryTest {
+    private final Category model = new Category();
+
+    /**
+     * Model tests for Category
+     */
+    @Test
+    public void testCategory() {
+        // TODO: test Category
+    }
+
+    /**
+     * Test the property 'id'
+     */
+    @Test
+    public void idTest() {
+        // TODO: test id
+    }
+
+    /**
+     * Test the property 'name'
+     */
+    @Test
+    public void nameTest() {
+        // TODO: test name
+    }
+
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/test/java/com/baeldung/petstore/client/model/ModelApiResponseTest.java

@@ -0,0 +1,57 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.model;
+
+import org.junit.Test;
+
+
+/**
+ * Model tests for ModelApiResponse
+ */
+public class ModelApiResponseTest {
+    private final ModelApiResponse model = new ModelApiResponse();
+
+    /**
+     * Model tests for ModelApiResponse
+     */
+    @Test
+    public void testModelApiResponse() {
+        // TODO: test ModelApiResponse
+    }
+
+    /**
+     * Test the property 'code'
+     */
+    @Test
+    public void codeTest() {
+        // TODO: test code
+    }
+
+    /**
+     * Test the property 'type'
+     */
+    @Test
+    public void typeTest() {
+        // TODO: test type
+    }
+
+    /**
+     * Test the property 'message'
+     */
+    @Test
+    public void messageTest() {
+        // TODO: test message
+    }
+
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/test/java/com/baeldung/petstore/client/model/OrderTest.java

@@ -0,0 +1,81 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.model;
+
+import org.junit.Test;
+
+
+/**
+ * Model tests for Order
+ */
+public class OrderTest {
+    private final Order model = new Order();
+
+    /**
+     * Model tests for Order
+     */
+    @Test
+    public void testOrder() {
+        // TODO: test Order
+    }
+
+    /**
+     * Test the property 'id'
+     */
+    @Test
+    public void idTest() {
+        // TODO: test id
+    }
+
+    /**
+     * Test the property 'petId'
+     */
+    @Test
+    public void petIdTest() {
+        // TODO: test petId
+    }
+
+    /**
+     * Test the property 'quantity'
+     */
+    @Test
+    public void quantityTest() {
+        // TODO: test quantity
+    }
+
+    /**
+     * Test the property 'shipDate'
+     */
+    @Test
+    public void shipDateTest() {
+        // TODO: test shipDate
+    }
+
+    /**
+     * Test the property 'status'
+     */
+    @Test
+    public void statusTest() {
+        // TODO: test status
+    }
+
+    /**
+     * Test the property 'complete'
+     */
+    @Test
+    public void completeTest() {
+        // TODO: test complete
+    }
+
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/test/java/com/baeldung/petstore/client/model/PetTest.java

@@ -0,0 +1,81 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.model;
+
+import org.junit.Test;
+
+
+/**
+ * Model tests for Pet
+ */
+public class PetTest {
+    private final Pet model = new Pet();
+
+    /**
+     * Model tests for Pet
+     */
+    @Test
+    public void testPet() {
+        // TODO: test Pet
+    }
+
+    /**
+     * Test the property 'id'
+     */
+    @Test
+    public void idTest() {
+        // TODO: test id
+    }
+
+    /**
+     * Test the property 'category'
+     */
+    @Test
+    public void categoryTest() {
+        // TODO: test category
+    }
+
+    /**
+     * Test the property 'name'
+     */
+    @Test
+    public void nameTest() {
+        // TODO: test name
+    }
+
+    /**
+     * Test the property 'photoUrls'
+     */
+    @Test
+    public void photoUrlsTest() {
+        // TODO: test photoUrls
+    }
+
+    /**
+     * Test the property 'tags'
+     */
+    @Test
+    public void tagsTest() {
+        // TODO: test tags
+    }
+
+    /**
+     * Test the property 'status'
+     */
+    @Test
+    public void statusTest() {
+        // TODO: test status
+    }
+
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/test/java/com/baeldung/petstore/client/model/TagTest.java

@@ -0,0 +1,49 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.model;
+
+import org.junit.Test;
+
+
+/**
+ * Model tests for Tag
+ */
+public class TagTest {
+    private final Tag model = new Tag();
+
+    /**
+     * Model tests for Tag
+     */
+    @Test
+    public void testTag() {
+        // TODO: test Tag
+    }
+
+    /**
+     * Test the property 'id'
+     */
+    @Test
+    public void idTest() {
+        // TODO: test id
+    }
+
+    /**
+     * Test the property 'name'
+     */
+    @Test
+    public void nameTest() {
+        // TODO: test name
+    }
+
+}

spring-swagger-codegen/spring-openapi-generator-api-client/src/test/java/com/baeldung/petstore/client/model/UserTest.java

@@ -0,0 +1,97 @@
+/*
+ * Swagger Petstore
+ * This is a sample server Petstore server.  You can find out more about Swagger at [http://swagger.io](http://swagger.io) or on [irc.freenode.net, #swagger](http://swagger.io/irc/).  For this sample, you can use the api key `special-key` to test the authorization filters.
+ *
+ * The version of the OpenAPI document: 1.0.3
+ * Contact: apiteam@swagger.io
+ *
+ * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
+ * https://openapi-generator.tech
+ * Do not edit the class manually.
+ */
+
+
+package com.baeldung.petstore.client.model;
+
+import org.junit.Test;
+
+
+/**
+ * Model tests for User
+ */
+public class UserTest {
+    private final User model = new User();
+
+    /**
+     * Model tests for User
+     */
+    @Test
+    public void testUser() {
+        // TODO: test User
+    }
+
+    /**
+     * Test the property 'id'
+     */
+    @Test
+    public void idTest() {
+        // TODO: test id
+    }
+
+    /**
+     * Test the property 'username'
+     */
+    @Test
+    public void usernameTest() {
+        // TODO: test username
+    }
+
+    /**
+     * Test the property 'firstName'
+     */
+    @Test
+    public void firstNameTest() {
+        // TODO: test firstName
+    }
+
+    /**
+     * Test the property 'lastName'
+     */
+    @Test
+    public void lastNameTest() {
+        // TODO: test lastName
+    }
+
+    /**
+     * Test the property 'email'
+     */
+    @Test
+    public void emailTest() {
+        // TODO: test email
+    }
+
+    /**
+     * Test the property 'password'
+     */
+    @Test
+    public void passwordTest() {
+        // TODO: test password
+    }
+
+    /**
+     * Test the property 'phone'
+     */
+    @Test
+    public void phoneTest() {
+        // TODO: test phone
+    }
+
+    /**
+     * Test the property 'userStatus'
+     */
+    @Test
+    public void userStatusTest() {
+        // TODO: test userStatus
+    }
+
+}