Merge pull request #4320 from softjake/master

BAEL-1764 Code update for Spring RestTemplate Exception Handling article.

spring-rest-simple/pom.xml

@@ -31,7 +31,8 @@
         </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-test</artifactId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <scope>test</scope>
         </dependency>
 
         <!-- Spring -->
@@ -240,7 +241,7 @@
                 <artifactId>cargo-maven2-plugin</artifactId>
                 <version>${cargo-maven2-plugin.version}</version>
                 <configuration>
-                    <wait>true</wait>
+                    <!--<wait>true</wait> caused errors on commit-->
                     <container>
                         <containerId>tomcat8x</containerId>
                         <type>embedded</type>

spring-rest-simple/src/main/java/org/baeldung/config/WebConfig.java

@@ -1,8 +1,5 @@
 package org.baeldung.config;
 
-import java.text.SimpleDateFormat;
-import java.util.List;
-
 import org.baeldung.config.converter.KryoHttpMessageConverter;
 import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;
@@ -19,6 +16,9 @@ import org.springframework.web.servlet.config.annotation.ContentNegotiationConfi
 import org.springframework.web.servlet.config.annotation.EnableWebMvc;
 import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
 
+import java.text.SimpleDateFormat;
+import java.util.List;
+
 /*
  * Please note that main web configuration is in src/main/webapp/WEB-INF/api-servlet.xml
  */

spring-rest-simple/src/main/java/org/baeldung/web/exception/NotFoundException.java

@@ -0,0 +1,4 @@
+package org.baeldung.web.exception;
+
+public class NotFoundException extends RuntimeException {
+}

spring-rest-simple/src/main/java/org/baeldung/web/handler/RestTemplateResponseErrorHandler.java

@@ -0,0 +1,43 @@
+package org.baeldung.web.handler;
+
+import org.baeldung.web.exception.NotFoundException;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.client.ClientHttpResponse;
+import org.springframework.stereotype.Component;
+import org.springframework.web.client.ResponseErrorHandler;
+
+import java.io.IOException;
+
+@Component
+public class RestTemplateResponseErrorHandler
+    implements ResponseErrorHandler {
+
+    @Override
+    public boolean hasError(ClientHttpResponse httpResponse)
+        throws IOException {
+
+        return (httpResponse
+          .getStatusCode()
+          .series() == HttpStatus.Series.CLIENT_ERROR || httpResponse
+          .getStatusCode()
+          .series() == HttpStatus.Series.SERVER_ERROR);
+    }
+
+    @Override
+    public void handleError(ClientHttpResponse httpResponse)
+        throws IOException {
+
+        if (httpResponse
+          .getStatusCode()
+          .series() == HttpStatus.Series.SERVER_ERROR) {
+            //Handle SERVER_ERROR
+        } else if (httpResponse
+          .getStatusCode()
+          .series() == HttpStatus.Series.CLIENT_ERROR) {
+            //Handle CLIENT_ERROR
+            if (httpResponse.getStatusCode() == HttpStatus.NOT_FOUND) {
+                throw new NotFoundException();
+            }
+        }
+    }
+}

spring-rest-simple/src/main/java/org/baeldung/web/model/Bar.java

@@ -0,0 +1,22 @@
+package org.baeldung.web.model;
+
+public class Bar {
+    private String id;
+    private String name;
+
+    public String getId() {
+        return id;
+    }
+
+    public void setId(String id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+}

spring-rest-simple/src/main/java/org/baeldung/web/service/BarConsumerService.java

@@ -0,0 +1,26 @@
+package org.baeldung.web.service;
+
+import org.baeldung.web.handler.RestTemplateResponseErrorHandler;
+import org.baeldung.web.model.Bar;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.web.client.RestTemplateBuilder;
+import org.springframework.stereotype.Service;
+import org.springframework.web.client.RestTemplate;
+
+@Service
+public class BarConsumerService {
+
+    private RestTemplate restTemplate;
+
+    @Autowired
+    public BarConsumerService(RestTemplateBuilder restTemplateBuilder) {
+        RestTemplate restTemplate = restTemplateBuilder
+          .errorHandler(new RestTemplateResponseErrorHandler())
+          .build();
+    }
+
+    public Bar fetchBarById(String barId) {
+        return restTemplate.getForObject("/bars/4242", Bar.class);
+    }
+
+}

spring-rest-simple/src/test/java/org/baeldung/web/handler/RestTemplateResponseErrorHandlerIntegrationTest.java

@@ -0,0 +1,48 @@
+package org.baeldung.web.handler;
+
+import org.baeldung.web.exception.NotFoundException;
+import org.baeldung.web.model.Bar;
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.client.RestClientTest;
+import org.springframework.boot.web.client.RestTemplateBuilder;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.HttpStatus;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.web.client.ExpectedCount;
+import org.springframework.test.web.client.MockRestServiceServer;
+import org.springframework.web.client.RestTemplate;
+
+import static org.springframework.test.web.client.match.MockRestRequestMatchers.method;
+import static org.springframework.test.web.client.match.MockRestRequestMatchers.requestTo;
+import static org.springframework.test.web.client.response.MockRestResponseCreators.withStatus;
+
+@RunWith(SpringRunner.class)
+@ContextConfiguration(classes = { NotFoundException.class, Bar.class })
+@RestClientTest
+public class RestTemplateResponseErrorHandlerIntegrationTest {
+
+    @Autowired private MockRestServiceServer server;
+    @Autowired private RestTemplateBuilder builder;
+
+    @Test(expected = NotFoundException.class)
+    public void givenRemoteApiCall_when404Error_thenThrowNotFound() {
+        Assert.assertNotNull(this.builder);
+        Assert.assertNotNull(this.server);
+
+        RestTemplate restTemplate = this.builder
+          .errorHandler(new RestTemplateResponseErrorHandler())
+          .build();
+
+        this.server
+          .expect(ExpectedCount.once(), requestTo("/bars/4242"))
+          .andExpect(method(HttpMethod.GET))
+          .andRespond(withStatus(HttpStatus.NOT_FOUND));
+
+        Bar response = restTemplate.getForObject("/bars/4242", Bar.class);
+        this.server.verify();
+    }
+}