Merge pull request #75 from eugenp/master

update

algorithms-miscellaneous-1/README.md

@@ -10,4 +10,4 @@ This module contains articles about algorithms. Some classes of algorithms, e.g.
 - [Introduction to Minimax Algorithm](https://www.baeldung.com/java-minimax-algorithm)
 - [How to Calculate Levenshtein Distance in Java?](https://www.baeldung.com/java-levenshtein-distance)
 - [How to Find the Kth Largest Element in Java](https://www.baeldung.com/java-kth-largest-element)
-- More articles: [[next -->]](/../algorithms-miscellaneous-2)
+- More articles: [[next -->]](/algorithms-miscellaneous-2)

algorithms-miscellaneous-2/README.md

@@ -14,4 +14,4 @@ This module contains articles about algorithms. Some classes of algorithms, e.g.
 - [Displaying Money Amounts in Words](https://www.baeldung.com/java-money-into-words)
 - [A Collaborative Filtering Recommendation System in Java](https://www.baeldung.com/java-collaborative-filtering-recommendations)
 - [Implementing A* Pathfinding in Java](https://www.baeldung.com/java-a-star-pathfinding)
-- More articles: [[<-- prev]](/../algorithms-miscellaneous-1) [[next -->]](/../algorithms-miscellaneous-3)
+- More articles: [[<-- prev]](/algorithms-miscellaneous-1) [[next -->]](/algorithms-miscellaneous-3)

algorithms-miscellaneous-5/README.md

@@ -15,5 +15,5 @@ This module contains articles about algorithms. Some classes of algorithms, e.g.
 - [Maximum Subarray Problem](https://www.baeldung.com/java-maximum-subarray)
 - [How to Merge Two Sorted Arrays](https://www.baeldung.com/java-merge-sorted-arrays)
 - [Median of Stream of Integers using Heap](https://www.baeldung.com/java-stream-integers-median-using-heap)
-- More articles: [[<-- prev]](/../algorithms-miscellaneous-4) [[next -->]](/../algorithms-miscellaneous-6)
+- More articles: [[<-- prev]](/algorithms-miscellaneous-4) [[next -->]](/algorithms-miscellaneous-6)
 

algorithms-miscellaneous-6/README.md

@@ -10,4 +10,4 @@
 - [Implementing a 2048 Solver in Java](https://www.baeldung.com/2048-java-solver)
 - [Finding Top K Elements in an Array](https://www.baeldung.com/java-array-top-elements)
 - [Reversing a Linked List in Java](https://www.baeldung.com/java-reverse-linked-list)
-- More articles: [[<-- prev]](/../algorithms-miscellaneous-5)
+- More articles: [[<-- prev]](/algorithms-miscellaneous-5)

apache-spark/README.md

@@ -8,3 +8,4 @@ This module contains articles about Apache Spark
 - [Building a Data Pipeline with Kafka, Spark Streaming and Cassandra](https://www.baeldung.com/kafka-spark-data-pipeline)
 - [Machine Learning with Spark MLlib](https://www.baeldung.com/spark-mlib-machine-learning)
 - [Introduction to Spark Graph Processing with GraphFrames](https://www.baeldung.com/spark-graph-graphframes)
+- [Apache Spark: Differences between Dataframes, Datasets and RDDs](https://www.baeldung.com/java-spark-dataframe-dataset-rdd)

core-java-modules/core-java-9-jigsaw/src/modules/com.baeldung.student.service.dbimpl/com/baeldung/student/service/dbimpl/StudentDbService.java

@@ -19,12 +19,12 @@ public class StudentDbService implements StudentService {
     }
 
     public Student update(Student student) {
-        logger.log(Level.INFO, "Updating sutdent in DB...");
+        logger.log(Level.INFO, "Updating student in DB...");
         return student;
     }
 
     public String delete(String registrationId) {
-        logger.log(Level.INFO, "Deleteing sutdent in DB...");
+        logger.log(Level.INFO, "Deleting student in DB...");
         return registrationId;
     }
 }

core-java-modules/core-java-collections-3/src/main/java/com/baeldung/collections/removeallperformance/HashSetBenchmark.java

@@ -33,11 +33,15 @@ public class HashSetBenchmark {
         private List<Employee> employeeList1 = new ArrayList<>();
         private Set<Employee> employeeSet2 = new HashSet<>();
         private List<Employee> employeeList2 = new ArrayList<>();
+        private Set<Employee> employeeSet3 = new HashSet<>();
+        private Set<Employee> employeeSet4 = new HashSet<>();
 
         private long set1Size = 60000;
         private long list1Size = 50000;
         private long set2Size = 50000;
         private long list2Size = 60000;
+        private long set3Size = 50000;
+        private long set4Size = 60000;
 
         @Setup(Level.Trial)
         public void setUp() {
@@ -58,6 +62,14 @@ public class HashSetBenchmark {
                 employeeList2.add(new Employee(i, RandomStringUtils.random(7, true, false)));
             }
             
+            for (long i = 0; i < set3Size; i++) {
+                employeeSet3.add(new Employee(i, RandomStringUtils.random(7, true, false)));
+            }
+
+            for (long i = 0; i < set4Size; i++) {
+                employeeSet4.add(new Employee(i, RandomStringUtils.random(7, true, false)));
+            }
+
         }
 
     }
@@ -72,6 +84,11 @@ public class HashSetBenchmark {
         return state.employeeSet2.removeAll(state.employeeList2);
     }
     
+    @Benchmark
+    public boolean given_SizeOfHashsetSmallerThanSizeOfAnotherHashSet_When_RemoveAllFromHashSet_Then_GoodPerformance(MyState state) {
+        return state.employeeSet3.removeAll(state.employeeSet4);
+    }
+
     public static void main(String[] args) throws Exception {
         Options options = new OptionsBuilder().include(HashSetBenchmark.class.getSimpleName())
             .threads(1)

core-java-modules/core-java-concurrency-advanced-3/src/main/java/com/baeldung/deadlockAndLivelock/LivelockExample.java

@@ -73,7 +73,7 @@ public class LivelockExample {
 
     public void tryLock(Lock lock, long millis) {
         try {
-            lock.tryLock(10, TimeUnit.MILLISECONDS);
+            lock.tryLock(millis, TimeUnit.MILLISECONDS);
         } catch (InterruptedException e) {
             e.printStackTrace();
         }

core-java-modules/core-java-exceptions-3/src/main/java/com/baeldung/exceptions/classcastexception/Animal.java

@@ -0,0 +1,6 @@
+package com.baeldung.exceptions.classcastexception;
+
+public interface Animal {
+
+    String getName();
+}

core-java-modules/core-java-exceptions-3/src/main/java/com/baeldung/exceptions/classcastexception/Box.java

@@ -0,0 +1,14 @@
+package com.baeldung.exceptions.classcastexception;
+
+public class Box<T> {
+
+    private T content;
+
+    public T getContent() {
+        return content;
+    }
+
+    public void setContent(T content) {
+        this.content = content;
+    }
+}

core-java-modules/core-java-exceptions-3/src/main/java/com/baeldung/exceptions/classcastexception/Frog.java

@@ -0,0 +1,9 @@
+package com.baeldung.exceptions.classcastexception;
+
+public class Frog extends Reptile {
+
+    @Override
+    public String getName() {
+        return super.getName() + ": Frog";
+    }
+}

core-java-modules/core-java-exceptions-3/src/main/java/com/baeldung/exceptions/classcastexception/Mammal.java

@@ -0,0 +1,9 @@
+package com.baeldung.exceptions.classcastexception;
+
+public class Mammal implements Animal {
+
+    @Override
+    public String getName() {
+        return "Mammal";
+    }
+}

core-java-modules/core-java-exceptions-3/src/main/java/com/baeldung/exceptions/classcastexception/Reptile.java

@@ -0,0 +1,9 @@
+package com.baeldung.exceptions.classcastexception;
+
+public class Reptile implements Animal {
+
+    @Override
+    public String getName() {
+        return "Reptile";
+    }
+}

core-java-modules/core-java-exceptions-3/src/test/java/com/baeldung/exceptions/classcastexception/CheckedCastsUnitTest.java

@@ -0,0 +1,40 @@
+package com.baeldung.exceptions.classcastexception;
+
+import org.junit.Test;
+
+import java.io.Serializable;
+
+public class CheckedCastsUnitTest {
+
+    @Test(expected = ClassCastException.class)
+    public void givenBaseTypeVariableReferencingChildInstance_whenCastToIncompatibleSubtype_thenClassCastException() {
+        Animal animal = new Frog();
+
+        //A checked downcast to Mammal is incompatible from Frog because Frog is not a subtype of Mammal.
+        Mammal mammal = (Mammal) animal;
+    }
+
+    @Test(expected = ClassCastException.class)
+    public void givenBaseTypeVariableReferencingChildInstance_whenCastToIncompatibleInterface_thenClassCastException() {
+        Animal animal = new Frog();
+
+        //A checked cast to Serializable is incompatible from Frog because Frog is not a subtype of Serializable.
+        Serializable serial = (Serializable) animal;
+    }
+
+    @Test(expected = ClassCastException.class)
+    public void givenObjectVariableReferencingPrimitiveArray_whenCastToBoxedTypeArray_thenClassCastException() {
+        Object primitives = new int[1];
+
+        //A checked cast to Integer[] is incompatible from primitive arrays. Auto-boxing does not work for arrays.
+        Integer[] integers = (Integer[]) primitives;
+    }
+
+    @Test(expected = ClassCastException.class)
+    public void givenObjectVariableReferencingPrimitiveArray_whenCastToPromotedTypeArray_thenClassCastException() {
+        Object primitives = new int[1];
+
+        //A checked cast to long[] is incompatible from int[]. Type promotion does not work for arrays.
+        long[] longs = (long[]) primitives;
+    }
+}

core-java-modules/core-java-exceptions-3/src/test/java/com/baeldung/exceptions/classcastexception/GenericConversionUnitTest.java

@@ -0,0 +1,21 @@
+package com.baeldung.exceptions.classcastexception;
+
+import org.junit.Test;
+
+public class GenericConversionUnitTest {
+
+    @Test(expected = ClassCastException.class)
+    public void givenIncompatibleType_whenConvertInstanceOfObject_thenClassCastException() {
+        // Should have been null, but due to type erasure, inside convertInstanceOfObject,
+        // it will attempt to cast to Object instead of String, so it casts to Object, which is always possible.
+        String shouldBeNull = convertInstanceOfObject(123);
+    }
+
+    public static <T> T convertInstanceOfObject(Object o) {
+        try {
+            return (T) o; // Casts to Object due to type erasure
+        } catch (ClassCastException e) {
+            return null; // Will never reach this
+        }
+    }
+}

core-java-modules/core-java-exceptions-3/src/test/java/com/baeldung/exceptions/classcastexception/UncheckedConversionUnitTest.java

@@ -0,0 +1,17 @@
+package com.baeldung.exceptions.classcastexception;
+
+import org.junit.Test;
+
+public class UncheckedConversionUnitTest {
+
+    @Test(expected = ClassCastException.class)
+    public void givenPollutedGenericType_whenGetProperty_thenClassCastException() {
+        Box<Long> originalBox = new Box<>();
+        Box raw = originalBox;
+        raw.setContent(2.5);
+        Box<Long> bound = (Box<Long>) raw;
+
+        //An incompatible element was found in the raw box.
+        Long content = bound.getContent();
+    }
+}

core-java-modules/core-java-lang-3/README.md

@@ -7,4 +7,5 @@ This module contains articles about core features in the Java language
 - [When are Static Variables Initialized in Java?](https://www.baeldung.com/java-static-variables-initialization)
 - [Checking if a Class Exists in Java](https://www.baeldung.com/java-check-class-exists)
 - [The Difference Between a.getClass() and A.class in Java](https://www.baeldung.com/java-getclass-vs-class)
+- [Constants in Java: Patterns and Anti-Patterns](https://www.baeldung.com/java-constants-good-practices)
 - [[<-- Prev]](/core-java-modules/core-java-lang-2)

core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/Calculator.java

@@ -0,0 +1,37 @@
+package com.baeldung.constantspatterns;
+
+public class Calculator {
+    public static final double PI = 3.14159265359;
+    private static final double UPPER_LIMIT = 0x1.fffffffffffffP+1023;
+
+    public enum Operation {
+        ADD, SUBTRACT, DIVIDE, MULTIPLY
+    }
+
+    public double operateOnTwoNumbers(double numberOne, double numberTwo, Operation operation) {
+        if (numberOne > UPPER_LIMIT) {
+            throw new IllegalArgumentException("'numberOne' is too large");
+        }
+        if (numberTwo > UPPER_LIMIT) {
+            throw new IllegalArgumentException("'numberTwo' is too large");
+        }
+        double answer = 0;
+
+        switch (operation) {
+        case ADD:
+            answer = numberOne + numberTwo;
+            break;
+        case SUBTRACT:
+            answer = numberOne - numberTwo;
+            break;
+        case DIVIDE:
+            answer = numberOne / numberTwo;
+            break;
+        case MULTIPLY:
+            answer = numberOne * numberTwo;
+            break;
+        }
+
+        return answer;
+    }
+}

core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/CalculatorConstants.java

@@ -0,0 +1,10 @@
+package com.baeldung.constantspatterns;
+
+public interface CalculatorConstants {
+    double PI = 3.14159265359;
+    double UPPER_LIMIT = 0x1.fffffffffffffP+1023;
+
+    enum Operation {
+        ADD, SUBTRACT, MULTIPLY, DIVIDE
+    };
+}

core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/GeometryCalculator.java

@@ -0,0 +1,32 @@
+package com.baeldung.constantspatterns;
+
+public class GeometryCalculator implements CalculatorConstants {
+    public static final double UPPER_LIMIT = 100000000000000000000.0;
+
+    public double operateOnTwoNumbers(double numberOne, double numberTwo, Operation operation) {
+        if (numberOne > UPPER_LIMIT) {
+            throw new IllegalArgumentException("'numberOne' is too large");
+        }
+        if (numberTwo > UPPER_LIMIT) {
+            throw new IllegalArgumentException("'numberTwo' is too large");
+        }
+        double answer = 0;
+
+        switch (operation) {
+        case ADD:
+            answer = numberOne + numberTwo;
+            break;
+        case SUBTRACT:
+            answer = numberOne - numberTwo;
+            break;
+        case DIVIDE:
+            answer = numberOne / numberTwo;
+            break;
+        case MULTIPLY:
+            answer = numberOne * numberTwo;
+            break;
+        }
+
+        return answer;
+    }
+}

core-java-modules/core-java-lang-3/src/main/java/com/baeldung/constantspatterns/calculations/MathConstants.java

@@ -0,0 +1,16 @@
+package com.baeldung.constantspatterns.calculations;
+
+public final class MathConstants {
+    public static final double PI = 3.14159265359;
+    static final double GOLDEN_RATIO = 1.6180;
+    static final double GRAVITATIONAL_ACCELERATION = 9.8;
+    static final double EULERS_NUMBER = 2.7182818284590452353602874713527;
+
+    public enum Operation {
+        ADD, SUBTRACT, DIVIDE, MULTIPLY
+    }
+
+    private MathConstants() {
+
+    }
+}

core-java-modules/core-java-lang-3/src/test/java/com/baeldung/constantspatterns/ConstantPatternUnitTest.java

@@ -0,0 +1,23 @@
+package com.baeldung.constantspatterns;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import org.junit.Test;
+
+public class ConstantPatternUnitTest {
+    @Test
+    public void givenTwoNumbersAndAdd_whenCallingCalculatorOperatOneTwoNumbers_thenCorrectAnswerReturned() {
+        Calculator calculator = new Calculator();
+        double expected = 4;
+        double answer = calculator.operateOnTwoNumbers(2, 2, Calculator.Operation.ADD);
+        assertEquals(expected, answer);
+    }
+    
+    @Test
+    public void givenTwoNumbersAndAdd_whenCallingGeometryCalculatorOperatOneTwoNumbers_thenCorrectAnswerReturned() {
+        GeometryCalculator calculator = new GeometryCalculator();
+        double expected = 4;
+        double answer = calculator.operateOnTwoNumbers(2, 2, GeometryCalculator.Operation.ADD);
+        assertEquals(expected, answer);
+    }
+}

core-java-modules/core-java-networking-2/README.md

@@ -14,4 +14,5 @@ This module contains articles about networking in Java
 - [Handling java.net.ConnectException](https://www.baeldung.com/java-net-connectexception)
 - [Getting MAC addresses in Java](https://www.baeldung.com/java-mac-address)
 - [Sending Emails with Attachments in Java](https://www.baeldung.com/java-send-emails-attachments)
+- [Finding a Free Port in Java](https://www.baeldung.com/java-free-port)
 - [[<-- Prev]](/core-java-modules/core-java-networking)

core-java-modules/core-java-security-2/src/main/java/com/baeldung/hashing/SHACommonUtils.java

@@ -3,7 +3,7 @@ package com.baeldung.hashing;
 class SHACommonUtils {
 
     public static String bytesToHex(byte[] hash) {
-        StringBuffer hexString = new StringBuffer();
+        StringBuilder hexString = new StringBuilder(2 * hash.length);
         for (byte h : hash) {
             String hex = Integer.toHexString(0xff & h);
             if (hex.length() == 1)

ddd/pom.xml

@@ -104,16 +104,12 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-surefire-plugin</artifactId>
-                <version>${maven-surefire-plugin.version}</version>
             </plugin>
         </plugins>
     </build>
 
     <properties>
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-
         <joda-money.version>1.0.1</joda-money.version>
 
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
     </properties>
 </project>

netflix-modules/mantis/pom.xml

@@ -0,0 +1,78 @@
+<?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>mantis</artifactId>
+    <name>Mantis</name>
+    <packaging>jar</packaging>
+    <description>Sample project for Netflix Mantis</description>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-boot-2</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../../parent-boot-2</relativePath>
+    </parent>
+
+    <dependencies>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter</artifactId>
+            <version>2.1.3.RELEASE</version>
+        </dependency>
+
+        <dependency>
+            <groupId>io.mantisrx</groupId>
+            <artifactId>mantis-runtime</artifactId>
+            <version>1.2.63</version>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.slf4j</groupId>
+                    <artifactId>slf4j-log4j12</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+            <version>2.10.2</version>
+        </dependency>
+
+        <dependency>
+            <groupId>net.andreinc.mockneat</groupId>
+            <artifactId>mockneat</artifactId>
+            <version>0.3.8</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>1.18.12</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-webflux</artifactId>
+            <version>5.0.9.RELEASE</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>io.projectreactor.netty</groupId>
+            <artifactId>reactor-netty</artifactId>
+            <version>0.9.12.RELEASE</version>
+            <scope>test</scope>
+        </dependency>
+
+    </dependencies>
+
+    <repositories>
+        <repository>
+            <id>SpringLibReleaseRepo</id>
+            <url>https://repo.spring.io/libs-release/</url>
+        </repository>
+    </repositories>
+
+</project>

netflix-modules/mantis/src/main/java/com/baeldung/netflix/mantis/MantisApplication.java

@@ -0,0 +1,23 @@
+package com.baeldung.netflix.mantis;
+
+import com.baeldung.netflix.mantis.job.LogAggregationJob;
+import io.mantisrx.runtime.executor.LocalJobExecutorNetworked;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@Slf4j
+@SpringBootApplication
+public class MantisApplication implements CommandLineRunner {
+
+    public static void main(String[] args) {
+        SpringApplication.run(MantisApplication.class, args);
+    }
+
+    @Override
+    public void run(String... args) {
+        LocalJobExecutorNetworked.execute(new LogAggregationJob().getJobInstance());
+    }
+
+}

netflix-modules/mantis/src/main/java/com/baeldung/netflix/mantis/job/LogAggregationJob.java

@@ -0,0 +1,37 @@
+package com.baeldung.netflix.mantis.job;
+
+import com.baeldung.netflix.mantis.model.LogAggregate;
+import com.baeldung.netflix.mantis.source.RandomLogSource;
+import com.baeldung.netflix.mantis.stage.CountLogStage;
+import com.baeldung.netflix.mantis.stage.GroupLogStage;
+import com.baeldung.netflix.mantis.stage.TransformLogStage;
+import io.mantisrx.runtime.Job;
+import io.mantisrx.runtime.MantisJob;
+import io.mantisrx.runtime.MantisJobProvider;
+import io.mantisrx.runtime.Metadata;
+import io.mantisrx.runtime.sink.Sink;
+import io.mantisrx.runtime.sink.Sinks;
+import lombok.AllArgsConstructor;
+import lombok.NoArgsConstructor;
+
+@NoArgsConstructor
+@AllArgsConstructor
+public class LogAggregationJob extends MantisJobProvider<LogAggregate> {
+
+    private Sink<LogAggregate> sink = Sinks.eagerSubscribe(Sinks.sse(LogAggregate::toJsonString));
+
+    @Override
+    public Job<LogAggregate> getJobInstance() {
+
+        return MantisJob
+          .source(new RandomLogSource())
+          .stage(new TransformLogStage(), TransformLogStage.stageConfig())
+          .stage(new GroupLogStage(), GroupLogStage.config())
+          .stage(new CountLogStage(), CountLogStage.config())
+          .sink(sink)
+          .metadata(new Metadata.Builder().build())
+          .create();
+
+    }
+
+}

netflix-modules/mantis/src/main/java/com/baeldung/netflix/mantis/job/LogCollectingJob.java

@@ -0,0 +1,34 @@
+package com.baeldung.netflix.mantis.job;
+
+import com.baeldung.netflix.mantis.model.LogEvent;
+import com.baeldung.netflix.mantis.sink.LogSink;
+import com.baeldung.netflix.mantis.source.RandomLogSource;
+import com.baeldung.netflix.mantis.stage.TransformLogStage;
+import io.mantisrx.runtime.Job;
+import io.mantisrx.runtime.MantisJob;
+import io.mantisrx.runtime.MantisJobProvider;
+import io.mantisrx.runtime.Metadata;
+import io.mantisrx.runtime.ScalarToScalar;
+import io.mantisrx.runtime.sink.Sink;
+import lombok.AllArgsConstructor;
+import lombok.NoArgsConstructor;
+
+@NoArgsConstructor
+@AllArgsConstructor
+public class LogCollectingJob extends MantisJobProvider<LogEvent> {
+
+    private Sink<LogEvent> sink = new LogSink();
+
+    @Override
+    public Job<LogEvent> getJobInstance() {
+
+        return MantisJob
+          .source(new RandomLogSource())
+          .stage(new TransformLogStage(), new ScalarToScalar.Config<>())
+          .sink(sink)
+          .metadata(new Metadata.Builder().build())
+          .create();
+
+    }
+
+}

netflix-modules/mantis/src/main/java/com/baeldung/netflix/mantis/model/LogAggregate.java

@@ -0,0 +1,28 @@
+package com.baeldung.netflix.mantis.model;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import io.mantisrx.runtime.codec.JsonType;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@NoArgsConstructor
+@AllArgsConstructor
+public class LogAggregate implements JsonType {
+
+    private static final ObjectMapper mapper = new ObjectMapper();
+
+    private Integer count;
+    private String level;
+
+    public String toJsonString() {
+        try {
+            return mapper.writeValueAsString(this);
+        } catch (JsonProcessingException e) {
+            return null;
+        }
+    }
+
+}

netflix-modules/mantis/src/main/java/com/baeldung/netflix/mantis/model/LogEvent.java

@@ -0,0 +1,35 @@
+package com.baeldung.netflix.mantis.model;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import io.mantisrx.runtime.codec.JsonType;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+@Getter
+@Setter
+@NoArgsConstructor
+public class LogEvent implements JsonType {
+
+    private static final ObjectMapper mapper = new ObjectMapper();
+
+    private Long index;
+    private String level;
+    private String message;
+
+    public LogEvent(String[] parts) {
+        this.index = Long.valueOf(parts[0]);
+        this.level = parts[1];
+        this.message = parts[2];
+    }
+
+    public String toJsonString() {
+        try {
+            return mapper.writeValueAsString(this);
+        } catch (JsonProcessingException e) {
+            return null;
+        }
+    }
+
+}

netflix-modules/mantis/src/main/java/com/baeldung/netflix/mantis/sink/LogSink.java

@@ -0,0 +1,37 @@
+package com.baeldung.netflix.mantis.sink;
+
+import com.baeldung.netflix.mantis.model.LogEvent;
+import io.mantisrx.runtime.Context;
+import io.mantisrx.runtime.PortRequest;
+import io.mantisrx.runtime.sink.SelfDocumentingSink;
+import io.mantisrx.runtime.sink.ServerSentEventsSink;
+import io.mantisrx.runtime.sink.Sink;
+import io.mantisrx.runtime.sink.predicate.Predicate;
+import rx.Observable;
+
+public class LogSink implements Sink<LogEvent> {
+
+    @Override
+    public void call(Context context, PortRequest portRequest, Observable<LogEvent> logEventObservable) {
+
+        SelfDocumentingSink<LogEvent> sink = new ServerSentEventsSink.Builder<LogEvent>()
+          .withEncoder(LogEvent::toJsonString)
+          .withPredicate(filterByLogMessage())
+          .build();
+
+        logEventObservable.subscribe();
+
+        sink.call(context, portRequest, logEventObservable);
+    }
+
+    private Predicate<LogEvent> filterByLogMessage() {
+        return new Predicate<>("filter by message",
+          parameters -> {
+            if (parameters != null && parameters.containsKey("filter")) {
+                return logEvent -> logEvent.getMessage().contains(parameters.get("filter").get(0));
+            }
+            return logEvent -> true;
+        });
+    }
+
+}

netflix-modules/mantis/src/main/java/com/baeldung/netflix/mantis/source/RandomLogSource.java

@@ -0,0 +1,46 @@
+package com.baeldung.netflix.mantis.source;
+
+import io.mantisrx.runtime.Context;
+import io.mantisrx.runtime.source.Index;
+import io.mantisrx.runtime.source.Source;
+import lombok.extern.slf4j.Slf4j;
+import net.andreinc.mockneat.MockNeat;
+import rx.Observable;
+
+import java.util.Date;
+import java.util.concurrent.TimeUnit;
+
+@Slf4j
+public class RandomLogSource implements Source<String> {
+
+    private MockNeat mockDataGenerator;
+
+    @Override
+    public void init(Context context, Index index) {
+        mockDataGenerator = MockNeat.threadLocal();
+    }
+
+    @Override
+    public Observable<Observable<String>> call(Context context, Index index) {
+        return Observable.just(
+          Observable
+            .interval(250, TimeUnit.MILLISECONDS)
+            .map(this::createRandomLogEvent));
+    }
+
+    private String createRandomLogEvent(Long tick) {
+        String level = mockDataGenerator.probabilites(String.class)
+          .add(0.5, "INFO")
+          .add(0.3, "WARN")
+          .add(0.2, "ERROR")
+          .get();
+
+        String message = mockDataGenerator.probabilites(String.class)
+          .add(0.5, "login attempt")
+          .add(0.5, "user created")
+          .get();
+
+        return tick + "#" + level + "#" + message;
+    }
+
+}

netflix-modules/mantis/src/main/java/com/baeldung/netflix/mantis/stage/CountLogStage.java

@@ -0,0 +1,58 @@
+package com.baeldung.netflix.mantis.stage;
+
+import com.baeldung.netflix.mantis.model.LogAggregate;
+import com.baeldung.netflix.mantis.model.LogEvent;
+import io.mantisrx.common.MantisGroup;
+import io.mantisrx.runtime.Context;
+import io.mantisrx.runtime.GroupToScalar;
+import io.mantisrx.runtime.codec.JacksonCodecs;
+import io.mantisrx.runtime.computation.GroupToScalarComputation;
+import io.mantisrx.runtime.parameter.ParameterDefinition;
+import io.mantisrx.runtime.parameter.type.IntParameter;
+import io.mantisrx.runtime.parameter.validator.Validators;
+import rx.Observable;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+
+public class CountLogStage implements GroupToScalarComputation<String, LogEvent, LogAggregate> {
+
+    private int duration;
+
+    @Override
+    public void init(Context context) {
+        duration = (int)context.getParameters().get("LogAggregationDuration", 1000);
+    }
+
+    @Override
+    public Observable<LogAggregate> call(Context context, Observable<MantisGroup<String, LogEvent>> mantisGroup) {
+        return mantisGroup
+          .window(duration, TimeUnit.MILLISECONDS)
+          .flatMap(o -> o.groupBy(MantisGroup::getKeyValue)
+            .flatMap(group -> group.reduce(0, (count, value) ->  count = count + 1)
+              .map((count) -> new LogAggregate(count, group.getKey()))
+            ));
+    }
+
+    public static GroupToScalar.Config<String, LogEvent, LogAggregate> config(){
+        return new GroupToScalar.Config<String, LogEvent, LogAggregate>()
+          .description("sum events for a log level")
+          .codec(JacksonCodecs.pojo(LogAggregate.class))
+          .withParameters(getParameters());
+    }
+
+    public static List<ParameterDefinition<?>> getParameters() {
+        List<ParameterDefinition<?>> params = new ArrayList<>();
+
+        params.add(new IntParameter()
+          .name("LogAggregationDuration")
+          .description("window size for aggregation in milliseconds")
+          .validator(Validators.range(100, 10000))
+          .defaultValue(5000)
+          .build())	;
+
+        return params;
+    }
+    
+}

netflix-modules/mantis/src/main/java/com/baeldung/netflix/mantis/stage/GroupLogStage.java

@@ -0,0 +1,25 @@
+package com.baeldung.netflix.mantis.stage;
+
+import com.baeldung.netflix.mantis.model.LogEvent;
+import io.mantisrx.common.MantisGroup;
+import io.mantisrx.runtime.Context;
+import io.mantisrx.runtime.ScalarToGroup;
+import io.mantisrx.runtime.codec.JacksonCodecs;
+import io.mantisrx.runtime.computation.ToGroupComputation;
+import rx.Observable;
+
+public class GroupLogStage implements ToGroupComputation<LogEvent, String, LogEvent> {
+
+    @Override
+    public Observable<MantisGroup<String, LogEvent>> call(Context context, Observable<LogEvent> logEvent) {
+        return logEvent.map(log -> new MantisGroup<>(log.getLevel(), log));
+    }
+
+    public static ScalarToGroup.Config<LogEvent, String, LogEvent> config(){
+        return new ScalarToGroup.Config<LogEvent, String, LogEvent>()
+          .description("Group event data by level")
+          .codec(JacksonCodecs.pojo(LogEvent.class))
+          .concurrentInput();
+    }
+    
+}

netflix-modules/mantis/src/main/java/com/baeldung/netflix/mantis/stage/TransformLogStage.java

@@ -0,0 +1,24 @@
+package com.baeldung.netflix.mantis.stage;
+
+import com.baeldung.netflix.mantis.model.LogEvent;
+import io.mantisrx.runtime.Context;
+import io.mantisrx.runtime.ScalarToScalar;
+import io.mantisrx.runtime.codec.JacksonCodecs;
+import io.mantisrx.runtime.computation.ScalarComputation;
+import rx.Observable;
+
+public class TransformLogStage implements ScalarComputation<String, LogEvent> {
+
+    @Override
+    public Observable<LogEvent> call(Context context, Observable<String> logEntry) {
+        return logEntry
+          .map(log -> log.split("#"))
+          .filter(parts -> parts.length == 3)
+          .map(LogEvent::new);
+    }
+
+    public static ScalarToScalar.Config<String, LogEvent> stageConfig() {
+        return new ScalarToScalar.Config<String, LogEvent>()
+          .codec(JacksonCodecs.pojo(LogEvent.class));
+    }
+}

netflix-modules/mantis/src/test/java/com/baeldung/netflix/mantis/job/LogAggregationJobIntegrationTest.java

@@ -0,0 +1,56 @@
+package com.baeldung.netflix.mantis.job;
+
+import com.baeldung.netflix.mantis.model.LogAggregate;
+import io.mantisrx.runtime.PortRequest;
+import io.mantisrx.runtime.sink.Sinks;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import static java.util.Arrays.asList;
+import static java.util.Optional.of;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class LogAggregationJobIntegrationTest extends MantisJobTestBase<LogAggregate> {
+
+    private final static int PORT = 7382;
+    private final static String SINK_URL = "http://localhost:" + PORT;
+
+    @BeforeAll
+    static void beforeAll() {
+        start(new LogAggregationJob((context, portRequest, logAggregateObservable) -> {
+            logAggregateObservable.subscribe();
+            Sinks.sse(LogAggregate::toJsonString).call(context, new PortRequest(PORT), logAggregateObservable);
+        }));
+    }
+
+    @Override
+    public String getSinkUrl() {
+        return SINK_URL;
+    }
+
+    @Override
+    public Class<LogAggregate> getEventType() {
+        return LogAggregate.class;
+    }
+
+    @Test
+    void whenReadingFromSink_thenShouldRetrieveCorrectNumberOfLogAggregates() {
+        assertEquals(of(5L), sinkStream.take(5).count().blockOptional());
+    }
+
+    @Test
+    void whenReadingFromSink_thenShouldRetrieveLogAggregate() {
+        assertNotNull(sinkStream.take(1).blockFirst());
+    }
+
+    @Test
+    void whenReadingFromSink_thenShouldRetrieveValidLogAggregate() {
+        LogAggregate logAggregate = sinkStream.take(1).blockFirst();
+
+        assertTrue(asList("ERROR", "WARN", "INFO").contains(logAggregate.getLevel()));
+        assertTrue(logAggregate.getCount() > 0);
+    }
+
+}

netflix-modules/mantis/src/test/java/com/baeldung/netflix/mantis/job/LogCollectingJobIntegrationTest.java

@@ -0,0 +1,73 @@
+package com.baeldung.netflix.mantis.job;
+
+import com.baeldung.netflix.mantis.model.LogEvent;
+import com.baeldung.netflix.mantis.sink.LogSink;
+import io.mantisrx.runtime.Context;
+import io.mantisrx.runtime.PortRequest;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import rx.Observable;
+
+import static java.util.Arrays.asList;
+import static java.util.Optional.of;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+class LogCollectingJobIntegrationTest extends MantisJobTestBase<LogEvent> {
+
+    private final static int PORT = 7381;
+    private final static String SINK_URL = "http://localhost:" + PORT;
+
+    @BeforeAll
+    static void beforeAll() {
+
+        start(new LogCollectingJob(new LogSink() {
+
+            @Override
+            public void call(Context context, PortRequest portRequest, Observable<LogEvent> observable) {
+                super.call(context, new PortRequest(PORT), observable);
+            }
+
+        }));
+
+    }
+
+    @Override
+    public String getSinkUrl() {
+        return SINK_URL;
+    }
+
+    @Override
+    public Class<LogEvent> getEventType() {
+        return LogEvent.class;
+    }
+
+    @Test
+    void whenReadingFromSink_thenShouldRetrieveCorrectNumberOfLogEvents() {
+        assertEquals(of(5L), sinkStream.take(5).count().blockOptional());
+    }
+
+    @Test
+    void whenReadingFromSink_thenShouldRetrieveLogEvent() {
+        assertNotNull(sinkStream.take(1).blockFirst());
+    }
+
+    @Test
+    void whenReadingFromSink_thenShouldRetrieveValidLogEvent() {
+        LogEvent logEvent = sinkStream.take(1).blockFirst();
+
+        assertTrue(asList("ERROR", "WARN", "INFO").contains(logEvent.getLevel()));
+        assertTrue(asList("login attempt", "user created").contains(logEvent.getMessage()));
+    }
+
+    @Test
+    void whenReadingFromSink_thenShouldRetrieveFilteredLogEvents() {
+        getSinkStream(SINK_URL + "?filter=login")
+          .take(7)
+          .toStream().forEach(
+            logEvent -> assertEquals("login attempt", logEvent.getMessage())
+        );
+    }
+
+}

netflix-modules/mantis/src/test/java/com/baeldung/netflix/mantis/job/MantisJobTestBase.java

@@ -0,0 +1,49 @@
+package com.baeldung.netflix.mantis.job;
+
+import io.mantisrx.runtime.Job;
+import io.mantisrx.runtime.MantisJobProvider;
+import io.mantisrx.runtime.executor.LocalJobExecutorNetworked;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeEach;
+import org.springframework.web.reactive.function.client.WebClient;
+import reactor.core.publisher.Flux;
+import reactor.util.retry.Retry;
+
+import java.time.Duration;
+
+public abstract class MantisJobTestBase<T> {
+
+    private static Job jobInstance;
+    Flux<T> sinkStream;
+
+    public abstract String getSinkUrl();
+    public abstract Class<T> getEventType();
+
+    @BeforeEach
+    void setUp() {
+        sinkStream = getSinkStream(getSinkUrl());
+    }
+
+    @AfterAll
+    static void afterAll() {
+        stopJob();
+    }
+
+    protected Flux<T> getSinkStream(String sinkUrl) {
+        return WebClient.builder().build().get()
+          .uri(sinkUrl)
+          .retrieve()
+          .bodyToFlux(getEventType())
+          .retryWhen(Retry.fixedDelay(10, Duration.ofMillis(2000)));
+    }
+
+    static <T> void start(MantisJobProvider<T> job) {
+        jobInstance = job.getJobInstance();
+        new Thread(() -> LocalJobExecutorNetworked.execute(jobInstance)).start();
+    }
+
+    static void stopJob() {
+        jobInstance.getLifecycle().shutdown();
+    }
+
+}

netflix-modules/pom.xml

@@ -15,6 +15,7 @@
 
     <modules>
         <module>genie</module>
+        <module>mantis</module>
     </modules>
 
 </project>

persistence-modules/core-java-persistence-2/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [Getting Database URL From JDBC Connection Object](https://www.baeldung.com/jdbc-get-url-from-connection)

persistence-modules/core-java-persistence-2/pom.xml

@@ -0,0 +1,29 @@
+<?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>
+    <groupId>com.baeldung.core-java-persistence-2</groupId>
+    <artifactId>core-java-persistence-2</artifactId>
+    <version>0.1.0-SNAPSHOT</version>
+    <name>core-java-persistence-2</name>
+    <packaging>jar</packaging>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>persistence-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.h2database</groupId>
+            <artifactId>h2</artifactId>
+            <version>${h2.version}</version>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <h2.version>1.4.200</h2.version>
+    </properties>
+
+</project>

persistence-modules/core-java-persistence-2/src/main/java/com/baeldung/getdburl/DBConfiguration.java

@@ -0,0 +1,13 @@
+package com.baeldung.getdburl;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+
+public class DBConfiguration {
+
+    public static Connection getConnection() throws Exception {
+        Class.forName("org.h2.Driver");
+        String url = "jdbc:h2:mem:testdb";
+        return DriverManager.getConnection(url, "user", "password");
+    }
+}

persistence-modules/core-java-persistence-2/src/test/java/com/baeldung/getdburl/DBConfigurationUnitTest.java

@@ -0,0 +1,18 @@
+package com.baeldung.getdburl;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.sql.Connection;
+
+import org.junit.jupiter.api.Test;
+
+class DBConfigurationUnitTest {
+
+    @Test
+    void givenConnectionObject_whenExtractMetaData_thenGetDbURL() throws Exception {
+        Connection connection = DBConfiguration.getConnection();
+        String dbUrl = connection.getMetaData().getURL();
+        assertEquals("jdbc:h2:mem:testdb", dbUrl);
+    }
+
+}

persistence-modules/flyway-repair/pom.xml

@@ -76,10 +76,6 @@
     <properties>
         <flyway.configFiles>src/main/resources/application-${spring-boot.run.profiles}.properties</flyway.configFiles>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/flyway/pom.xml

@@ -66,10 +66,6 @@
         <flyway-core.version>5.2.3</flyway-core.version>
         <flyway-maven-plugin.version>5.0.2</flyway-maven-plugin.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/jpabootstrap/application/Application.java

@@ -8,7 +8,7 @@ public class Application {
     
     public static void main(String[] args) {
         EntityManager entityManager = getJpaEntityManager();
-        User user = entityManager.find(User.class, 1);
+        User user = entityManager.find(User.class, 1l);
         System.out.println(user);
         entityManager.getTransaction().begin();
         user.setName("John");

persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/onetoone/sharedkeybased/Address.java

@@ -1,9 +1,9 @@
 package com.baeldung.hibernate.onetoone.sharedkeybased;
 
-
 import javax.persistence.Column;
 import javax.persistence.Entity;
 import javax.persistence.Id;
+import javax.persistence.JoinColumn;
 import javax.persistence.MapsId;
 import javax.persistence.OneToOne;
 import javax.persistence.Table;
@@ -13,7 +13,7 @@ import javax.persistence.Table;
 public class Address {
 
     @Id
-    @Column(name = "id")
+    @Column(name = "user_id")
     private Long id;
 
     @Column(name = "street")
@@ -24,6 +24,7 @@ public class Address {
 
     @OneToOne
     @MapsId
+    @JoinColumn(name = "user_id")
     private User user;
 
     public Long getId() {

persistence-modules/hibernate-jpa/src/main/java/com/baeldung/hibernate/onetoone/sharedkeybased/User.java

@@ -8,6 +8,7 @@ import javax.persistence.GeneratedValue;
 import javax.persistence.GenerationType;
 import javax.persistence.Id;
 import javax.persistence.OneToOne;
+import javax.persistence.PrimaryKeyJoinColumn;
 import javax.persistence.Table;
 
 @Entity
@@ -22,6 +23,7 @@ public class User {
     private String userName;
 
     @OneToOne(mappedBy = "user", cascade = CascadeType.ALL)
+    @PrimaryKeyJoinColumn
     private Address address;
 
     public Long getId() {

persistence-modules/pom.xml

@@ -17,6 +17,7 @@
         <module>apache-bookkeeper</module><!-- BAEL-2322 -->
         <module>apache-cayenne</module>
         <module>core-java-persistence</module>
+        <module>core-java-persistence-2</module>
         <module>deltaspike</module>
         <module>elasticsearch</module>
         <module>flyway</module>

persistence-modules/r2dbc/pom.xml

@@ -69,10 +69,6 @@
         <r2dbc-h2.version>0.8.1.RELEASE</r2dbc-h2.version>
         <h2.version>1.4.200</h2.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/redis/pom.xml

@@ -62,10 +62,6 @@
         <jedis.version>3.3.0</jedis.version>
         <epoll.version>4.1.50.Final</epoll.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-boot-mysql/pom.xml

@@ -40,10 +40,6 @@
     <properties>
         <mysql-connector-java.version>8.0.12</mysql-connector-java.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-boot-persistence-2/README.md

@@ -5,4 +5,5 @@
 - [Integrating Spring Boot with HSQLDB](https://www.baeldung.com/spring-boot-hsqldb)
 - [List of In-Memory Databases](https://www.baeldung.com/java-in-memory-databases)
 - [Oracle Connection Pooling With Spring](https://www.baeldung.com/spring-oracle-connection-pooling)
+- [Object States in Hibernate’s Session](https://www.baeldung.com/hibernate-session-object-states)
 - More articles: [[<-- prev]](../spring-boot-persistence)

persistence-modules/spring-boot-persistence-h2/pom.xml

@@ -47,10 +47,6 @@
         <start-class>com.baeldung.h2db.demo.server.SpringBootApp</start-class>
         <db-util.version>1.0.4</db-util.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-boot-persistence-mongodb/pom.xml

@@ -37,9 +37,5 @@
     </dependencies>
 
     <properties>
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 </project>

persistence-modules/spring-boot-persistence/pom.xml

@@ -76,11 +76,6 @@
     <properties>
         <mockito.version>2.23.0</mockito.version>
         <validation-api.version>2.0.1.Final</validation-api.version>
-
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-data-cassandra-reactive/pom.xml

@@ -54,10 +54,6 @@
         <spring-boot.version>2.2.6.RELEASE</spring-boot.version>
         <cassandra-unit-spring.version>3.11.2.0</cassandra-unit-spring.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-data-cassandra/pom.xml

@@ -105,10 +105,6 @@
         <cassandra-unit-shaded.version>2.1.9.2</cassandra-unit-shaded.version>
         <hector-core.version>2.0-0</hector-core.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-data-cosmosdb/pom.xml

@@ -17,10 +17,6 @@
         <java.version>1.8</java.version>
         <cosmodb.version>2.3.0</cosmodb.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
     
     <dependencies>

persistence-modules/spring-data-dynamodb/pom.xml

@@ -182,11 +182,6 @@
         <dynamodblocal.version>1.11.86</dynamodblocal.version>
         <dynamodblocal.repository.url>https://s3-us-west-2.amazonaws.com/dynamodb-local/release</dynamodblocal.repository.url>
         <maven-dependency-plugin.version>3.1.1</maven-dependency-plugin.version>
-
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-data-elasticsearch/pom.xml

@@ -69,10 +69,5 @@
         <fastjson.version>1.2.47</fastjson.version>
         <spatial4j.version>0.7</spatial4j.version>
         <jts.version>1.15.0</jts.version>
-
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 </project>

persistence-modules/spring-data-jdbc/pom.xml

@@ -28,9 +28,5 @@
 	</dependencies>
 
 	<properties>
-		<!-- testing -->
-		<maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-		<junit-jupiter.version>5.6.2</junit-jupiter.version>
-		<junit.version>4.13</junit.version>
 	</properties>
 </project>

persistence-modules/spring-data-jpa-annotations/pom.xml

@@ -73,10 +73,6 @@
         <postgresql.version>42.2.5</postgresql.version>
         <guava.version>21.0</guava.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-data-jpa-crud/pom.xml

@@ -16,10 +16,6 @@
 
     <dependencies>
         <!-- Prod Dependencies -->
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-web</artifactId>
-        </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-data-jpa</artifactId>
@@ -66,11 +62,6 @@
         <datasource-proxy.version>1.4.1</datasource-proxy.version>
         <guava.version>21.0</guava.version>
         <testcontainers.version>1.12.2</testcontainers.version>
-
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-data-jpa-enterprise/pom.xml

@@ -99,10 +99,6 @@
         <guava.version>21.0</guava.version>
         <testcontainers.version>1.12.2</testcontainers.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-data-jpa-filtering/pom.xml

@@ -73,10 +73,6 @@
         <postgresql.version>42.2.5</postgresql.version>
         <guava.version>21.0</guava.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-data-jpa-query-2/pom.xml

@@ -84,10 +84,6 @@
     </dependencies>
 
     <properties>
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
         <tomcat-dbcp.version>9.0.0.M26</tomcat-dbcp.version>
         <jta.version>1.1</jta.version>
         <guava.version>21.0</guava.version>

persistence-modules/spring-data-jpa-query/pom.xml

@@ -44,10 +44,6 @@
     <properties>
         <datasource-proxy.version>1.4.1</datasource-proxy.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-data-jpa-repo-2/pom.xml

@@ -44,9 +44,5 @@
     <properties>
         <guava.version>29.0-jre</guava.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 </project>

persistence-modules/spring-data-jpa-repo/pom.xml

@@ -50,9 +50,6 @@
     </dependencies>
 
     <properties>
-        <!-- testing -->
+      
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 </project>

persistence-modules/spring-data-keyvalue/pom.xml

@@ -29,9 +29,6 @@
     </dependencies>
 
     <properties>
-        <!-- testing -->
+   
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 </project>

persistence-modules/spring-data-mongodb/pom.xml

@@ -108,10 +108,6 @@
         <projectreactor.version>3.2.0.RELEASE</projectreactor.version>
         <mongodb-driver.version>4.0.5</mongodb-driver.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-data-redis/pom.xml

@@ -98,11 +98,6 @@
         <cglib.version>3.2.4</cglib.version>
         <nosqlunit.version>0.10.0</nosqlunit.version>
         <embedded-redis.version>0.6</embedded-redis.version>
-
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-data-redis/src/main/java/com/baeldung/spring/data/redis/config/RedisConfig.java

@@ -5,7 +5,6 @@ import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.annotation.PropertySource;
 import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;
-import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory;
 import org.springframework.data.redis.core.RedisTemplate;
 import org.springframework.data.redis.listener.ChannelTopic;
 import org.springframework.data.redis.listener.RedisMessageListenerContainer;

persistence-modules/spring-data-redis/src/test/java/com/baeldung/SpringContextTest.java

@@ -1,16 +1,32 @@
 package com.baeldung;
 
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
 import org.junit.Test;
-import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
-import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.annotation.DirtiesContext;
-import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.annotation.DirtiesContext.ClassMode;
 
-import com.baeldung.spring.data.redis.config.RedisConfig;
+import com.baeldung.spring.data.redis.SpringRedisApplication;
 
-@RunWith(SpringJUnit4ClassRunner.class)
+import redis.embedded.RedisServerBuilder;
-@ContextConfiguration(classes = RedisConfig.class)
+
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT, classes = SpringRedisApplication.class)
+@DirtiesContext(classMode = ClassMode.BEFORE_CLASS)
 public class SpringContextTest {
     
+    private static redis.embedded.RedisServer redisServer;
+    
+    @BeforeClass
+    public static void startRedisServer() {
+        redisServer = new RedisServerBuilder().port(6379).setting("maxmemory 256M").build();
+        redisServer.start();
+    }
+
+    @AfterClass
+    public static void stopRedisServer() {
+        redisServer.stop();
+    }
     @Test
     public void whenSpringContextIsBootstrapped_thenNoExceptions() {
     }

persistence-modules/spring-data-solr/pom.xml

@@ -46,10 +46,6 @@
     <properties>
         <spring-data-solr.version>2.0.5.RELEASE</spring-data-solr.version>
 
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 
 </project>

persistence-modules/spring-jdbc/pom.xml

@@ -18,7 +18,6 @@
         <dependency>
             <groupId>org.springframework.data</groupId>
             <artifactId>spring-data-jdbc</artifactId>
-            <version>${spring-data-jdbc.version}</version>
         </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
@@ -36,11 +35,5 @@
     </dependencies>
 
     <properties>
-        <spring-data-jdbc.version>2.0.3.RELEASE</spring-data-jdbc.version>
-
-        <!-- testing -->
-        <maven-surefire-plugin.version>2.22.2</maven-surefire-plugin.version>
-        <junit-jupiter.version>5.6.2</junit-jupiter.version>
-        <junit.version>4.13</junit.version>
     </properties>
 </project>

persistence-modules/spring-persistence-simple/README.md

@@ -7,6 +7,7 @@
 - [Transaction Propagation and Isolation in Spring @Transactional](https://www.baeldung.com/spring-transactional-propagation-isolation)
 - [JTA Transaction with Spring](https://www.baeldung.com/spring-vs-jta-transactional)
 - [Test a Mock JNDI Datasource with Spring](https://www.baeldung.com/spring-mock-jndi-datasource)
+- [Detecting If a Spring Transaction Is Active](https://www.baeldung.com/spring-transaction-active)
 
 ### Eclipse Config 
 After importing the project into Eclipse, you may see the following error:  

spring-boot-modules/spring-boot-annotations/README.md

@@ -9,3 +9,4 @@ This module contains articles about Spring Boot annotations
 - [Spring Web Annotations](https://www.baeldung.com/spring-mvc-annotations)
 - [Spring Core Annotations](https://www.baeldung.com/spring-core-annotations)
 - [Spring Bean Annotations](https://www.baeldung.com/spring-bean-annotations)
+- [Difference Between @ComponentScan and @EnableAutoConfiguration in Spring Boot](https://www.baeldung.com/spring-componentscan-vs-enableautoconfiguration)

spring-boot-modules/spring-boot-mvc-birt/pom.xml

@@ -4,11 +4,12 @@
          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>
 
+	<!--  this module should use the Boot parent directly to avoid inherit the logback dependency from our other parents -->
     <parent>
-        <groupId>com.baeldung.spring-boot-modules</groupId>
+        <groupId>org.springframework.boot</groupId>
-        <artifactId>spring-boot-modules</artifactId>
+        <artifactId>spring-boot-starter-parent</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
+        <version>2.1.1.RELEASE</version>
-        <relativePath>../</relativePath>
+        <relativePath/> <!-- lookup parent from repository -->
     </parent>
 
     <artifactId>spring-boot-mvc-birt</artifactId>
@@ -19,10 +20,6 @@
     <description>Module For Spring Boot Integration with BIRT</description>
 
     <dependencies>
-        <dependency>
-            <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter</artifactId>
-        </dependency>
 
         <dependency>
             <groupId>org.springframework.boot</groupId>
@@ -51,17 +48,14 @@
             <artifactId>org.eclipse.birt.runtime_4.8.0-20180626</artifactId>
             <version>${eclipse.birt.runtime.version}</version>
         </dependency>
-        <!-- https://mvnrepository.com/artifact/log4j/log4j -->
         <dependency>
             <groupId>log4j</groupId>
             <artifactId>log4j</artifactId>
             <version>${log4j.version}</version>
         </dependency>
-        <!-- https://mvnrepository.com/artifact/org.projectlombok/lombok -->
         <dependency>
             <groupId>org.projectlombok</groupId>
             <artifactId>lombok</artifactId>
-            <version>${lombok.version}</version>
             <scope>provided</scope>
         </dependency>
 
@@ -81,6 +75,7 @@
         <maven.compiler.source>1.8</maven.compiler.source>
         <maven.compiler.target>1.8</maven.compiler.target>
         <eclipse.birt.runtime.version>4.8.0</eclipse.birt.runtime.version>
+        <log4j.version>1.2.17</log4j.version>
     </properties>
 
 </project>

spring-boot-modules/spring-boot-mvc-birt/src/main/resources/log4j.properties

@@ -0,0 +1,9 @@
+# Set root logger level to DEBUG and its only appender to A1.
+log4j.rootLogger=DEBUG, A1
+
+# A1 is set to be a ConsoleAppender.
+log4j.appender.A1=org.apache.log4j.ConsoleAppender
+
+# A1 uses PatternLayout.
+log4j.appender.A1.layout=org.apache.log4j.PatternLayout
+log4j.appender.A1.layout.ConversionPattern=%-4r [%t] %-5p %c %x - %m%n

spring-boot-modules/spring-boot-mvc-birt/src/test/java/com/baeldung/birt/engine/SpringContextTest.java

@@ -0,0 +1,13 @@
+package com.baeldung.birt.engine;
+
+import org.junit.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+public class SpringContextTest {
+    
+    @Test
+    public void whenSpringContextIsBootstrapped_thenNoExceptions() {
+
+    }
+}

spring-cloud/spring-cloud-openfeign/src/main/java/com/baeldung/cloud/openfeign/config/ClientConfiguration.java

@@ -2,6 +2,7 @@ package com.baeldung.cloud.openfeign.config;
 
 import feign.Logger;
 import feign.RequestInterceptor;
+import feign.auth.BasicAuthRequestInterceptor;
 import feign.codec.ErrorDecoder;
 import feign.okhttp.OkHttpClient;
 import org.apache.http.entity.ContentType;
@@ -34,4 +35,9 @@ public class ClientConfiguration {
             requestTemplate.header("Accept", ContentType.APPLICATION_JSON.getMimeType());
         };
     }
+
+    // @Bean - uncomment to use this interceptor and remove @Bean from the requestInterceptor()
+    public BasicAuthRequestInterceptor basicAuthRequestInterceptor() {
+        return new BasicAuthRequestInterceptor("ajeje", "brazof");
+    }
 }

spring-jersey/pom.xml

@@ -226,7 +226,7 @@
         <httpcore.version>4.4.9</httpcore.version>
         <httpclient.version>4.5.5</httpclient.version>
         <javax.servlet-api.version>4.0.0</javax.servlet-api.version>
-        <wiremock.version>2.25.1</wiremock.version>
+        <wiremock.version>2.27.2</wiremock.version>
         <assertj-core.version>3.10.0</assertj-core.version>
         <spring-boot.version>1.5.10.RELEASE</spring-boot.version>
     </properties>

spring-jooq/pom.xml

@@ -206,7 +206,7 @@
         <lifecycle-mapping.version>1.0.0</lifecycle-mapping.version>
         <sql-maven-plugin.version>1.5</sql-maven-plugin.version>
         <properties-maven-plugin.version>1.0.0</properties-maven-plugin.version>
-        <start-class>org.jooq.example.spring.Application</start-class>
+        <h2.version>1.4.198</h2.version>
     </properties>
 
 </project>

spring-mvc-basics-2/src/main/java/com/baeldung/spring/configuration/EmailConfiguration.java

@@ -119,7 +119,7 @@ public class EmailConfiguration {
     @Bean
     public ResourceBundleMessageSource emailMessageSource() {
         final ResourceBundleMessageSource messageSource = new ResourceBundleMessageSource();
-        messageSource.setBasename("/mailMessages");
+        messageSource.setBasename("mailMessages");
         return messageSource;
     }
 

spring-mvc-basics-3/src/main/java/com/baeldung/validation/listvalidation/constraint/MaxSizeConstraintValidator.java

@@ -11,11 +11,7 @@ public class MaxSizeConstraintValidator implements ConstraintValidator<MaxSizeCo
 
     @Override
     public boolean isValid(List<Movie> values, ConstraintValidatorContext context) {
-        boolean isValid = true;
+       return values.size() <= 4;
-        if (values.size() > 4) {
-            isValid = false;
-        }
-        return isValid;
     }
 
 }

spring-resttemplate-2/src/main/java/com/baeldung/resttemplate/RestTemplateConfigurationApplication.java

@@ -1,7 +1,6 @@
 package com.baeldung.resttemplate;
 
 import org.springframework.boot.SpringApplication;
-import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 
 @SpringBootApplication

spring-resttemplate-2/src/main/java/com/baeldung/resttemplate/logging/RestTemplateConfigurationApplication.java

@@ -1,14 +0,0 @@
-package com.baeldung.resttemplate.logging;
-
-import org.springframework.boot.SpringApplication;
-import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
-import org.springframework.boot.autoconfigure.SpringBootApplication;
-
-@SpringBootApplication
-@EnableAutoConfiguration
-public class RestTemplateConfigurationApplication {
-
-    public static void main(String[] args) {
-        SpringApplication.run(RestTemplateConfigurationApplication.class, args);
-    }
-}

spring-resttemplate-2/src/test/java/com/baeldung/resttemplate/logging/LoggingInterceptor.java

@@ -14,16 +14,18 @@ import org.springframework.http.client.ClientHttpResponse;
 
 public class LoggingInterceptor implements ClientHttpRequestInterceptor {
 
-    final static Logger log = LoggerFactory.getLogger(LoggingInterceptor.class);
+    final static Logger LOGGER = LoggerFactory.getLogger(LoggingInterceptor.class);
 
     @Override
     public ClientHttpResponse intercept(HttpRequest req, byte[] reqBody, ClientHttpRequestExecution ex) throws IOException {
-        log.debug("Request body: {}", new String(reqBody, StandardCharsets.UTF_8));
+        LOGGER.debug("Request body: {}", new String(reqBody, StandardCharsets.UTF_8));
         ClientHttpResponse response = ex.execute(req, reqBody);
+        if (LOGGER.isDebugEnabled()) {
             InputStreamReader isr = new InputStreamReader(response.getBody(), StandardCharsets.UTF_8);
             String body = new BufferedReader(isr).lines()
                 .collect(Collectors.joining("\n"));
-        log.debug("Response body: {}", body);
+            LOGGER.debug("Response body: {}", body);
+        }
         return response;
     }
 }

spring-resttemplate-2/src/test/java/com/baeldung/resttemplate/logging/RestTemplateLoggingLiveTest.java

@@ -1,18 +1,21 @@
 package com.baeldung.resttemplate.logging;
 
-import static org.hamcrest.CoreMatchers.equalTo;
+import static org.junit.Assert.assertEquals;
-
-import static org.hamcrest.MatcherAssert.assertThat;
 
 import java.util.ArrayList;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
+import org.springframework.http.client.ClientHttpRequestFactory;
 import org.springframework.http.client.ClientHttpRequestInterceptor;
 import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
+import org.springframework.http.client.SimpleClientHttpRequestFactory;
+import org.springframework.http.client.BufferingClientHttpRequestFactory;
 import org.springframework.test.context.junit4.SpringRunner;
 import org.springframework.util.CollectionUtils;
 import org.springframework.web.client.RestTemplate;
@@ -22,6 +25,7 @@ import org.springframework.web.client.RestTemplate;
 public class RestTemplateLoggingLiveTest {
 
     private static final String baseUrl = "http://localhost:8080/spring-rest";
+    private static final Logger LOGGER = LoggerFactory.getLogger(RestTemplateLoggingLiveTest.class);
 
     @Test
     public void givenHttpClientConfiguration_whenSendGetForRequestEntity_thenRequestResponseFullLog() {
@@ -30,13 +34,22 @@ public class RestTemplateLoggingLiveTest {
         restTemplate.setRequestFactory(new HttpComponentsClientHttpRequestFactory());
 
         final ResponseEntity<String> response = restTemplate.postForEntity(baseUrl + "/persons", "my request body", String.class);
-        assertThat(response.getStatusCode(), equalTo(HttpStatus.OK));
+        assertEquals(HttpStatus.OK, response.getStatusCode());
+        assertEquals("[\"Lucie\",\"Jackie\",\"Danesh\",\"Tao\"]", response.getBody());
     }
 
     @Test
     public void givenLoggingInterceptorConfiguration_whenSendGetForRequestEntity_thenRequestResponseCustomLog() {
 
-        RestTemplate restTemplate = new RestTemplate();
+        RestTemplate restTemplate = null;
+        if (LOGGER.isDebugEnabled()) {
+            ClientHttpRequestFactory factory = new BufferingClientHttpRequestFactory(
+                    new SimpleClientHttpRequestFactory());
+            restTemplate = new RestTemplate(factory);
+        } else {
+            restTemplate = new RestTemplate();
+        }
+
         List<ClientHttpRequestInterceptor> interceptors = restTemplate.getInterceptors();
         if (CollectionUtils.isEmpty(interceptors)) {
             interceptors = new ArrayList<>();
@@ -45,6 +58,7 @@ public class RestTemplateLoggingLiveTest {
         restTemplate.setInterceptors(interceptors);
 
         final ResponseEntity<String> response = restTemplate.postForEntity(baseUrl + "/persons", "my request body", String.class);
-        assertThat(response.getStatusCode(), equalTo(HttpStatus.OK));
+        assertEquals(HttpStatus.OK, response.getStatusCode());
+        assertEquals("[\"Lucie\",\"Jackie\",\"Danesh\",\"Tao\"]", response.getBody());
     }
 }

spring-resttemplate-2/src/test/resources/application.properties

@@ -1,5 +1,5 @@
 logging.level.org.springframework.web.client.RestTemplate=DEBUG
-logging.level.com.baeldung.resttemplate.logging.LoggingInterceptor=DEBUG
+logging.level.com.baeldung.resttemplate.logging=DEBUG
 logging.level.org.apache.http=DEBUG
 logging.level.httpclient.wire=DEBUG
 logging.pattern.console=%20logger{20} - %msg%n

spring-security-modules/pom.xml

@@ -28,6 +28,7 @@
         <module>spring-security-web-login</module>
         <module>spring-security-web-persisted-remember-me</module>
         <module>spring-security-web-sockets</module>
+        <module>spring-security-legacy-oidc</module>
         <module>spring-security-oidc</module>
         <module>spring-security-okta</module>
         <module>spring-security-web-react</module>   

spring-security-modules/spring-security-legacy-oidc/README.md

@@ -0,0 +1,23 @@
+## Spring Security OpenID
+
+This module contains articles about OpenID with Spring Security
+
+### Relevant articles
+
+- [Spring Security and OpenID Connect (Legacy)](https://www.baeldung.com/spring-security-openid-connect-legacy)
+
+### OpenID Connect with Spring Security
+
+### Run the Project
+
+```
+mvn spring-boot:run
+```
+
+### Obtain Google App - Client ID, Secret
+
+- We need to get client id and client secret by creating a new project at [Google Developer Console](https://console.developers.google.com/project/_/apiui/credential?pli=1)
+- We can follow these instructions to register our client application on their platform
+
+- Once we have the client id and secret, we have to make sure we add them to the application.properties file.
+

spring-security-modules/spring-security-legacy-oidc/pom.xml

@@ -0,0 +1,58 @@
+<?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>spring-security-legacy-oidc</artifactId>
+    <name>spring-security-legacy-oidc</name>
+    <packaging>war</packaging>
+    <description>Spring OpenID Connect sample project</description>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-boot-2</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../../parent-boot-2</relativePath>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-security</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-tomcat</artifactId>
+        </dependency>
+
+        <dependency>
+            <groupId>org.springframework.security.oauth</groupId>
+            <artifactId>spring-security-oauth2</artifactId>
+            <version>${spring-security-oauth2.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.springframework.security</groupId>
+            <artifactId>spring-security-jwt</artifactId>
+            <version>${spring-security-jwt.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>com.auth0</groupId>
+            <artifactId>jwks-rsa</artifactId>
+            <version>${jwks-rsa.version}</version>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <spring-security-oauth2.version>2.2.1.RELEASE</spring-security-oauth2.version>
+        <spring-security-jwt.version>1.0.9.RELEASE</spring-security-jwt.version>
+        <jwks-rsa.version>0.3.0</jwks-rsa.version>
+    </properties>
+
+</project>

spring-security-modules/spring-security-legacy-oidc/src/main/java/com/baeldung/openid/oidc/GoogleOpenIdConnectConfig.java

@@ -0,0 +1,51 @@
+package com.baeldung.openid.oidc;
+
+import java.util.Arrays;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.oauth2.client.OAuth2ClientContext;
+import org.springframework.security.oauth2.client.OAuth2RestTemplate;
+import org.springframework.security.oauth2.client.resource.OAuth2ProtectedResourceDetails;
+import org.springframework.security.oauth2.client.token.grant.code.AuthorizationCodeResourceDetails;
+import org.springframework.security.oauth2.config.annotation.web.configuration.EnableOAuth2Client;
+
+@Configuration
+@EnableOAuth2Client
+public class GoogleOpenIdConnectConfig {
+    @Value("${google.clientId}")
+    private String clientId;
+
+    @Value("${google.clientSecret}")
+    private String clientSecret;
+
+    @Value("${google.accessTokenUri}")
+    private String accessTokenUri;
+
+    @Value("${google.userAuthorizationUri}")
+    private String userAuthorizationUri;
+
+    @Value("${google.redirectUri}")
+    private String redirectUri;
+
+    @Bean
+    public OAuth2ProtectedResourceDetails googleOpenId() {
+        final AuthorizationCodeResourceDetails details = new AuthorizationCodeResourceDetails();
+        details.setClientId(clientId);
+        details.setClientSecret(clientSecret);
+        details.setAccessTokenUri(accessTokenUri);
+        details.setUserAuthorizationUri(userAuthorizationUri);
+        details.setScope(Arrays.asList("openid", "email"));
+        details.setPreEstablishedRedirectUri(redirectUri);
+        details.setUseCurrentUri(false);
+        return details;
+    }
+
+    @Bean
+    public OAuth2RestTemplate googleOpenIdTemplate(final OAuth2ClientContext clientContext) {
+        final OAuth2RestTemplate template = new OAuth2RestTemplate(googleOpenId(), clientContext);
+        return template;
+    }
+
+}

spring-security-modules/spring-security-legacy-oidc/src/main/java/com/baeldung/openid/oidc/HomeController.java

@@ -0,0 +1,22 @@
+package com.baeldung.openid.oidc;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.ResponseBody;
+
+@Controller
+public class HomeController {
+    private final Logger logger = LoggerFactory.getLogger(getClass());
+
+    @RequestMapping("/")
+    @ResponseBody
+    public final String home() {
+        final String username = SecurityContextHolder.getContext().getAuthentication().getName();
+        logger.info(username);
+        return "Welcome, " + username;
+    }
+
+}

spring-security-modules/spring-security-legacy-oidc/src/main/java/com/baeldung/openid/oidc/OpenIdConnectFilter.java

@@ -0,0 +1,103 @@
+package com.baeldung.openid.oidc;
+
+import java.io.IOException;
+import java.net.URL;
+import java.security.interfaces.RSAPublicKey;
+import java.util.Date;
+import java.util.Map;
+
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.security.authentication.AuthenticationManager;
+import org.springframework.security.authentication.BadCredentialsException;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.AuthenticationException;
+import org.springframework.security.jwt.Jwt;
+import org.springframework.security.jwt.JwtHelper;
+import org.springframework.security.jwt.crypto.sign.RsaVerifier;
+import org.springframework.security.oauth2.client.OAuth2RestOperations;
+import org.springframework.security.oauth2.client.OAuth2RestTemplate;
+import org.springframework.security.oauth2.common.OAuth2AccessToken;
+import org.springframework.security.oauth2.common.exceptions.OAuth2Exception;
+import org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter;
+
+import com.auth0.jwk.Jwk;
+import com.auth0.jwk.JwkProvider;
+import com.auth0.jwk.UrlJwkProvider;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+public class OpenIdConnectFilter extends AbstractAuthenticationProcessingFilter {
+    @Value("${google.clientId}")
+    private String clientId;
+
+    @Value("${google.issuer}")
+    private String issuer;
+
+    @Value("${google.jwkUrl}")
+    private String jwkUrl;
+
+    public OAuth2RestOperations restTemplate;
+
+    public OpenIdConnectFilter(String defaultFilterProcessesUrl) {
+        super(defaultFilterProcessesUrl);
+        setAuthenticationManager(new NoopAuthenticationManager());
+    }
+
+    @Override
+    public Authentication attemptAuthentication(HttpServletRequest request, HttpServletResponse response) throws AuthenticationException, IOException, ServletException {
+
+        OAuth2AccessToken accessToken;
+        try {
+            accessToken = restTemplate.getAccessToken();
+        } catch (final OAuth2Exception e) {
+            throw new BadCredentialsException("Could not obtain access token", e);
+        }
+        try {
+            final String idToken = accessToken.getAdditionalInformation().get("id_token").toString();
+            String kid = JwtHelper.headers(idToken)
+                .get("kid");
+            final Jwt tokenDecoded = JwtHelper.decodeAndVerify(idToken, verifier(kid));
+            final Map<String, String> authInfo = new ObjectMapper().readValue(tokenDecoded.getClaims(), Map.class);
+            verifyClaims(authInfo);
+            final OpenIdConnectUserDetails user = new OpenIdConnectUserDetails(authInfo, accessToken);
+            return new UsernamePasswordAuthenticationToken(user, null, user.getAuthorities());
+        } catch (final Exception e) {
+            throw new BadCredentialsException("Could not obtain user details from token", e);
+        }
+
+    }
+
+    public void verifyClaims(Map claims) {
+        int exp = (int) claims.get("exp");
+        Date expireDate = new Date(exp * 1000L);
+        Date now = new Date();
+        if (expireDate.before(now) || !claims.get("iss").equals(issuer) || !claims.get("aud").equals(clientId)) {
+            throw new RuntimeException("Invalid claims");
+        }
+    }
+
+
+    private RsaVerifier verifier(String kid) throws Exception {
+        JwkProvider provider = new UrlJwkProvider(new URL(jwkUrl));
+        Jwk jwk = provider.get(kid);
+        return new RsaVerifier((RSAPublicKey) jwk.getPublicKey());
+    }
+
+    public void setRestTemplate(OAuth2RestTemplate restTemplate2) {
+        restTemplate = restTemplate2;
+
+    }
+
+    private static class NoopAuthenticationManager implements AuthenticationManager {
+
+        @Override
+        public Authentication authenticate(Authentication authentication) throws AuthenticationException {
+            throw new UnsupportedOperationException("No authentication should be done with this AuthenticationManager");
+        }
+
+    }
+}

spring-security-modules/spring-security-legacy-oidc/src/main/java/com/baeldung/openid/oidc/OpenIdConnectUserDetails.java

@@ -0,0 +1,81 @@
+package com.baeldung.openid.oidc;
+
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Map;
+
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.authority.SimpleGrantedAuthority;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.oauth2.common.OAuth2AccessToken;
+
+public class OpenIdConnectUserDetails implements UserDetails {
+
+    private static final long serialVersionUID = 1L;
+
+    private String userId;
+    private String username;
+    private OAuth2AccessToken token;
+
+    public OpenIdConnectUserDetails(Map<String, String> userInfo, OAuth2AccessToken token) {
+        this.userId = userInfo.get("sub");
+        this.username = userInfo.get("email");
+        this.token = token;
+    }
+
+    @Override
+    public String getUsername() {
+        return username;
+    }
+
+    @Override
+    public Collection<? extends GrantedAuthority> getAuthorities() {
+        return Arrays.asList(new SimpleGrantedAuthority("ROLE_USER"));
+    }
+
+    public String getUserId() {
+        return userId;
+    }
+
+    public void setUserId(String userId) {
+        this.userId = userId;
+    }
+
+    public OAuth2AccessToken getToken() {
+        return token;
+    }
+
+    public void setToken(OAuth2AccessToken token) {
+        this.token = token;
+    }
+
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    @Override
+    public String getPassword() {
+        return null;
+    }
+
+    @Override
+    public boolean isAccountNonExpired() {
+        return true;
+    }
+
+    @Override
+    public boolean isAccountNonLocked() {
+        return true;
+    }
+
+    @Override
+    public boolean isCredentialsNonExpired() {
+        return true;
+    }
+
+    @Override
+    public boolean isEnabled() {
+        return true;
+    }
+
+}