Merge branch 'eugenp:master' into master

apache-libraries/pom.xml

@@ -133,6 +133,11 @@
             <artifactId>jackson-databind</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.jayway.awaitility</groupId>
             <artifactId>awaitility</artifactId>
@@ -196,7 +201,6 @@
         <maven.compiler.source>1.8</maven.compiler.source>
         <maven.compiler.target>1.8</maven.compiler.target>
         <avro.version>1.8.2</avro.version>
-        <slf4j.version>1.7.25</slf4j.version>
         <beam.version>2.19.0</beam.version>
         <assertj.version>3.9.0</assertj.version>
         <bval.version>1.1.2</bval.version>

apache-libraries/src/test/java/com/baeldung/apache/beam/intro/WordCountUnitTest.java

@@ -10,7 +10,6 @@ import com.baeldung.apache.beam.intro.WordCount;
 public class WordCountUnitTest {
     
     @Test
-    // @Ignore
     public void givenInputFile_whenWordCountRuns_thenJobFinishWithoutError() {
         boolean jobDone = WordCount.wordCount("src/test/resources/wordcount.txt", "target/output");
         assertTrue(jobDone);

apache-thrift/pom.xml

@@ -29,7 +29,7 @@
         <dependency>
             <groupId>org.slf4j</groupId>
             <artifactId>slf4j-simple</artifactId>
-            <version>${org.slf4j.slf4j-simple.version}</version>
+            <version>${org.slf4j.version}</version>
             <scope>test</scope>
         </dependency>
     </dependencies>
@@ -61,7 +61,6 @@
     <properties>
         <thrift.version>0.10.0</thrift.version>
         <maven-thrift.version>0.1.11</maven-thrift.version>
-        <org.slf4j.slf4j-simple.version>1.7.12</org.slf4j.slf4j-simple.version>
         <build-helper-maven-plugin.version>3.0.0</build-helper-maven-plugin.version>
     </properties>
 

core-groovy-2/pom.xml

@@ -166,7 +166,6 @@
         <hsqldb.version>2.4.0</hsqldb.version>
         <spock-core.version>1.1-groovy-2.4</spock-core.version>
         <groovy-wslite.version>1.1.3</groovy-wslite.version>
-        <logback.version>1.2.3</logback.version>
         <groovy.version>2.5.7</groovy.version>
         <assembly.plugin.version>3.1.0</assembly.plugin.version>
         <compiler.plugin.version>3.8.0</compiler.plugin.version>

core-java-modules/core-java-16/README.md

@@ -1,3 +1,4 @@
 ### Relevant articles:
 
 - [Collect a Java Stream to an Immutable Collection](https://www.baeldung.com/java-stream-immutable-collection)
+- [Guide to mapMulti in Stream API](https://www.baeldung.com/java-mapmulti)

core-java-modules/core-java-arrays-operations-advanced/README.md

@@ -10,3 +10,4 @@ This module contains articles about advanced operations on arrays in Java. They
 - [Intersection Between two Integer Arrays](https://www.baeldung.com/java-array-intersection)
 - [Comparing Arrays in Java](https://www.baeldung.com/java-comparing-arrays)
 - [Concatenate Two Arrays in Java](https://www.baeldung.com/java-concatenate-arrays)
+- [Performance of System.arraycopy() vs. Arrays.copyOf()](https://www.baeldung.com/java-system-arraycopy-arrays-copyof-performance)

core-java-modules/core-java-arrays-operations-advanced/pom.xml

@@ -26,10 +26,50 @@
             <version>${assertj-core.version}</version>
             <scope>test</scope>
         </dependency>
+
+        <dependency>
+            <groupId>org.openjdk.jmh</groupId>
+            <artifactId>jmh-core</artifactId>
+            <version>${jmh.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.openjdk.jmh</groupId>
+            <artifactId>jmh-generator-annprocess</artifactId>
+            <version>${jmh.version}</version>
+        </dependency>
     </dependencies>
 
     <properties>
         <assertj-core.version>3.10.0</assertj-core.version>
+        <jmh.version>1.33</jmh.version>
     </properties>
 
+    <build>
+        <plugins>
+            <plugin>
+                <artifactId>maven-assembly-plugin</artifactId>
+                <configuration>
+                    <descriptorRefs>
+                        <descriptorRef>jar-with-dependencies</descriptorRef>
+                    </descriptorRefs>
+                    <archive>
+                        <manifest>
+                            <mainClass>com.baeldung.copyarraymethodsperformance.BenchmarkRunner</mainClass>
+                        </manifest>
+                    </archive>
+                </configuration>
+                <executions>
+                    <execution>
+                        <id>make-assembly</id>
+                        <phase>package</phase>
+                        <goals>
+                            <goal>single</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+
 </project>

core-java-modules/core-java-arrays-operations-advanced/src/main/java/com/baeldung/copyarraymethodsperformance/BenchmarkRunner.java

@@ -0,0 +1,11 @@
+package com.baeldung.copyarraymethodsperformance;
+
+public class BenchmarkRunner {
+
+    public static void main(String[] args) throws Exception {
+
+        org.openjdk.jmh.Main.main(args);
+
+    }
+
+}

core-java-modules/core-java-arrays-operations-advanced/src/main/java/com/baeldung/copyarraymethodsperformance/ObjectsCopyBenchmark.java

@@ -0,0 +1,42 @@
+package com.baeldung.copyarraymethodsperformance;
+
+import org.openjdk.jmh.annotations.*;
+
+import java.util.Arrays;
+import java.util.Random;
+import java.util.concurrent.TimeUnit;
+
+@BenchmarkMode(Mode.AverageTime)
+@State(Scope.Thread)
+@OutputTimeUnit(TimeUnit.NANOSECONDS)
+@Warmup(iterations = 10)
+@Fork(1)
+@Measurement(iterations = 100)
+public class ObjectsCopyBenchmark {
+
+    @Param({ "10", "1000000" })
+    public int SIZE;
+    Integer[] src;
+
+    @Setup
+    public void setup() {
+        Random r = new Random();
+        src = new Integer[SIZE];
+
+        for (int i = 0; i < SIZE; i++) {
+            src[i] = r.nextInt();
+        }
+    }
+
+    @Benchmark
+    public Integer[] systemArrayCopyBenchmark() {
+        Integer[] target = new Integer[SIZE];
+        System.arraycopy(src, 0, target, 0, SIZE);
+        return target;
+    }
+
+    @Benchmark
+    public Integer[] arraysCopyOfBenchmark() {
+        return Arrays.copyOf(src, SIZE);
+    }
+}

core-java-modules/core-java-arrays-operations-advanced/src/main/java/com/baeldung/copyarraymethodsperformance/PrimitivesCopyBenchmark.java

@@ -0,0 +1,43 @@
+package com.baeldung.copyarraymethodsperformance;
+
+import org.openjdk.jmh.annotations.*;
+
+import java.util.Arrays;
+import java.util.Random;
+import java.util.concurrent.TimeUnit;
+
+@BenchmarkMode(Mode.AverageTime)
+@State(Scope.Thread)
+@OutputTimeUnit(TimeUnit.NANOSECONDS)
+@Warmup(iterations = 10)
+@Fork(1)
+@Measurement(iterations = 100)
+public class PrimitivesCopyBenchmark {
+
+    @Param({ "10", "1000000" })
+    public int SIZE;
+
+    int[] src;
+
+    @Setup
+    public void setup() {
+        Random r = new Random();
+        src = new int[SIZE];
+
+        for (int i = 0; i < SIZE; i++) {
+            src[i] = r.nextInt();
+        }
+    }
+
+    @Benchmark
+    public int[] systemArrayCopyBenchmark() {
+        int[] target = new int[SIZE];
+        System.arraycopy(src, 0, target, 0, SIZE);
+        return target;
+    }
+
+    @Benchmark
+    public int[] arraysCopyOfBenchmark() {
+        return Arrays.copyOf(src, SIZE);
+    }
+}

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

@@ -8,4 +8,5 @@ This module contains articles about networking in Java
 - [Downloading Email Attachments in Java](https://www.baeldung.com/java-download-email-attachments)
 - [Connection Timeout vs. Read Timeout for Java Sockets](https://www.baeldung.com/java-socket-connection-read-timeout)
 - [Find Whether an IP Address Is in the Specified Range or Not in Java](https://www.baeldung.com/java-check-ip-address-range)
+- [Find the IP Address of a Client Connected to a Server](https://www.baeldung.com/java-client-get-ip-address)
 - [[<-- Prev]](/core-java-modules/core-java-networking-2)

core-java-modules/core-java-networking-3/src/main/java/com/baeldung/clientaddress/ApplicationClient.java

@@ -0,0 +1,39 @@
+package com.baeldung.clientaddress;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.PrintWriter;
+import java.net.Socket;
+
+public class ApplicationClient {
+
+    private Socket clientSocket;
+    private PrintWriter out;
+    private BufferedReader in;
+
+    public void connect(String ip, int port) throws IOException {
+        clientSocket = new Socket(ip, port);
+        out = new PrintWriter(clientSocket.getOutputStream(), true);
+        in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
+    }
+
+    public void sendGreetings(String msg) throws IOException {
+        out.println(msg);
+        String reply = in.readLine();
+        System.out.println("Reply received from the server :: " + reply);
+    }
+
+    public void disconnect() throws IOException {
+        in.close();
+        out.close();
+        clientSocket.close();
+    }
+
+    public static void main(String[] args) throws IOException {
+        ApplicationClient client = new ApplicationClient();
+        client.connect(args[0], Integer.parseInt(args[1])); // IP address and port number of the server
+        client.sendGreetings(args[2]); // greetings message
+        client.disconnect();
+    }
+}

core-java-modules/core-java-networking-3/src/main/java/com/baeldung/clientaddress/ApplicationServer.java

@@ -0,0 +1,51 @@
+package com.baeldung.clientaddress;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.PrintWriter;
+import java.net.InetSocketAddress;
+import java.net.ServerSocket;
+import java.net.Socket;
+
+public class ApplicationServer {
+
+    private ServerSocket serverSocket;
+    private Socket connectedSocket;
+    private PrintWriter out;
+    private BufferedReader in;
+
+    public void startServer(int port) throws IOException {
+        serverSocket = new ServerSocket(port);
+        connectedSocket = serverSocket.accept();
+
+        InetSocketAddress socketAddress = (InetSocketAddress) connectedSocket.getRemoteSocketAddress();
+        String clientIpAddress = socketAddress.getAddress()
+            .getHostAddress();
+        System.out.println("IP address of the connected client :: " + clientIpAddress);
+
+        out = new PrintWriter(connectedSocket.getOutputStream(), true);
+        in = new BufferedReader(new InputStreamReader(connectedSocket.getInputStream()));
+        String msg = in.readLine();
+        System.out.println("Message received from the client :: " + msg);
+        out.println("Hello Client !!");
+
+        closeIO();
+        stopServer();
+    }
+
+    private void closeIO() throws IOException {
+        in.close();
+        out.close();
+    }
+
+    private void stopServer() throws IOException {
+        connectedSocket.close();
+        serverSocket.close();
+    }
+
+    public static void main(String[] args) throws IOException {
+        ApplicationServer server = new ApplicationServer();
+        server.startServer(5000);
+    }
+}

core-java-modules/core-java-os/src/main/java/com/baeldung/java9/process/ProcessAPIEnhancements.java

@@ -0,0 +1,101 @@
+package com.baeldung.java9.process;
+
+import java.io.IOException;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.stream.Stream;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class ProcessAPIEnhancements {
+
+    static Logger log = LoggerFactory.getLogger(ProcessAPIEnhancements.class);
+
+    public static void main(String[] args) throws IOException, InterruptedException, ExecutionException {
+        infoOfCurrentProcess();
+        infoOfLiveProcesses();
+        infoOfSpawnProcess();
+        infoOfExitCallback();
+        infoOfChildProcess();
+    }
+
+    private static void infoOfCurrentProcess() {
+        ProcessHandle processHandle = ProcessHandle.current();
+        ProcessHandle.Info processInfo = processHandle.info();
+
+        log.info("PID: " + processHandle.pid());
+        log.info("Arguments: " + processInfo.arguments());
+        log.info("Command: " + processInfo.command());
+        log.info("Instant: " + processInfo.startInstant());
+        log.info("Total CPU duration: " + processInfo.totalCpuDuration());
+        log.info("User: " + processInfo.user());
+    }
+
+    private static void infoOfSpawnProcess() throws IOException {
+
+        String javaCmd = ProcessUtils.getJavaCmd().getAbsolutePath();
+        ProcessBuilder processBuilder = new ProcessBuilder(javaCmd, "-version");
+        Process process = processBuilder.inheritIO().start();
+        ProcessHandle processHandle = process.toHandle();
+        ProcessHandle.Info processInfo = processHandle.info();
+
+        log.info("PID: " + processHandle.pid());
+        log.info("Arguments: " + processInfo.arguments());
+        log.info("Command: " + processInfo.command());
+        log.info("Instant: " + processInfo.startInstant());
+        log.info("Total CPU duration: " + processInfo.totalCpuDuration());
+        log.info("User: " + processInfo.user());
+    }
+
+    private static void infoOfLiveProcesses() {
+        Stream<ProcessHandle> liveProcesses = ProcessHandle.allProcesses();
+        liveProcesses.filter(ProcessHandle::isAlive)
+            .forEach(ph -> {
+                log.info("PID: " + ph.pid());
+                log.info("Instance: " + ph.info().startInstant());
+                log.info("User: " + ph.info().user());
+            });
+    }
+
+    private static void infoOfChildProcess() throws IOException {
+        int childProcessCount = 5;
+        for (int i = 0; i < childProcessCount; i++) {
+            String javaCmd = ProcessUtils.getJavaCmd()
+              .getAbsolutePath();
+            ProcessBuilder processBuilder
+              = new ProcessBuilder(javaCmd, "-version");
+            processBuilder.inheritIO().start();
+        }
+
+        Stream<ProcessHandle> children = ProcessHandle.current()
+          .children();
+        children.filter(ProcessHandle::isAlive)
+          .forEach(ph -> log.info("PID: {}, Cmd: {}", ph.pid(), ph.info()
+            .command()));
+        Stream<ProcessHandle> descendants = ProcessHandle.current()
+          .descendants();
+        descendants.filter(ProcessHandle::isAlive)
+          .forEach(ph -> log.info("PID: {}, Cmd: {}", ph.pid(), ph.info()
+            .command()));
+    }
+
+    private static void infoOfExitCallback() throws IOException, InterruptedException, ExecutionException {
+        String javaCmd = ProcessUtils.getJavaCmd()
+          .getAbsolutePath();
+        ProcessBuilder processBuilder
+          = new ProcessBuilder(javaCmd, "-version");
+        Process process = processBuilder.inheritIO()
+          .start();
+        ProcessHandle processHandle = process.toHandle();
+
+        log.info("PID: {} has started", processHandle.pid());
+        CompletableFuture<ProcessHandle> onProcessExit = processHandle.onExit();
+        onProcessExit.get();
+        log.info("Alive: " + processHandle.isAlive());
+        onProcessExit.thenAccept(ph -> {
+            log.info("PID: {} has stopped", ph.pid());
+        });
+    }
+
+}

core-java-modules/core-java-os/src/test/java/com/baeldung/java9/process/ProcessAPIEnhancementsUnitTest.java

@@ -1,132 +0,0 @@
-package com.baeldung.java9.process;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
-
-import java.io.IOException;
-import java.util.concurrent.CompletableFuture;
-import java.util.stream.Stream;
-
-import org.junit.Test;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-/**
- * Created by sanaulla on 2/23/2017.
- */
-
-public class ProcessAPIEnhancementsUnitTest {
-
-    Logger log = LoggerFactory.getLogger(ProcessAPIEnhancementsUnitTest.class);
-
-    // @Test
-    // OS / Java version dependent
-    public void givenCurrentProcess_whenInvokeGetInfo_thenSuccess() throws IOException {
-        ProcessHandle processHandle = ProcessHandle.current();
-        ProcessHandle.Info processInfo = processHandle.info();
-        assertNotNull(processHandle.pid());
-        assertEquals(true, processInfo.arguments()
-          .isPresent());
-        assertEquals(true, processInfo.command()
-          .isPresent());
-        assertTrue(processInfo.command()
-          .get()
-          .contains("java"));
-
-        assertEquals(true, processInfo.startInstant()
-          .isPresent());
-        assertEquals(true, processInfo.totalCpuDuration()
-          .isPresent());
-        assertEquals(true, processInfo.user()
-          .isPresent());
-    }
-
-    // @Test
-    // OS / Java version dependent
-    public void givenSpawnProcess_whenInvokeGetInfo_thenSuccess() throws IOException {
-
-        String javaCmd = ProcessUtils.getJavaCmd()
-          .getAbsolutePath();
-        ProcessBuilder processBuilder = new ProcessBuilder(javaCmd, "-version");
-        Process process = processBuilder.inheritIO()
-          .start();
-        ProcessHandle processHandle = process.toHandle();
-        ProcessHandle.Info processInfo = processHandle.info();
-        assertNotNull(processHandle.pid());
-        assertEquals(true, processInfo.arguments()
-          .isPresent());
-        assertEquals(true, processInfo.command()
-          .isPresent());
-        assertTrue(processInfo.command()
-          .get()
-          .contains("java"));
-        assertEquals(true, processInfo.startInstant()
-          .isPresent());
-        assertEquals(false, processInfo.totalCpuDuration()
-          .isPresent());
-        assertEquals(true, processInfo.user()
-          .isPresent());
-    }
-
-    // @Test
-    // OS / Java version dependent
-    public void givenLiveProcesses_whenInvokeGetInfo_thenSuccess() {
-        Stream<ProcessHandle> liveProcesses = ProcessHandle.allProcesses();
-        liveProcesses.filter(ProcessHandle::isAlive)
-            .forEach(ph -> {
-                assertNotNull(ph.pid());
-                assertEquals(true, ph.info()
-                  .startInstant()
-                  .isPresent());
-                assertEquals(true, ph.info()
-                  .user()
-                  .isPresent());
-            });
-    }
-
-    // @Test
-    // OS / Java version dependent
-    public void givenProcess_whenGetChildProcess_thenSuccess() throws IOException {
-        int childProcessCount = 5;
-        for (int i = 0; i < childProcessCount; i++) {
-            String javaCmd = ProcessUtils.getJavaCmd()
-              .getAbsolutePath();
-            ProcessBuilder processBuilder
-              = new ProcessBuilder(javaCmd, "-version");
-            processBuilder.inheritIO().start();
-        }
-
-        Stream<ProcessHandle> children = ProcessHandle.current()
-          .children();
-        children.filter(ProcessHandle::isAlive)
-          .forEach(ph -> log.info("PID: {}, Cmd: {}", ph.pid(), ph.info()
-            .command()));
-        Stream<ProcessHandle> descendants = ProcessHandle.current()
-          .descendants();
-        descendants.filter(ProcessHandle::isAlive)
-          .forEach(ph -> log.info("PID: {}, Cmd: {}", ph.pid(), ph.info()
-            .command()));
-    }
-
-    // @Test
-    // OS / Java version dependent
-    public void givenProcess_whenAddExitCallback_thenSuccess() throws Exception {
-        String javaCmd = ProcessUtils.getJavaCmd()
-          .getAbsolutePath();
-        ProcessBuilder processBuilder
-          = new ProcessBuilder(javaCmd, "-version");
-        Process process = processBuilder.inheritIO()
-          .start();
-        ProcessHandle processHandle = process.toHandle();
-
-        log.info("PID: {} has started", processHandle.pid());
-        CompletableFuture<ProcessHandle> onProcessExit = processHandle.onExit();
-        onProcessExit.get();
-        assertEquals(false, processHandle.isAlive());
-        onProcessExit.thenAccept(ph -> {
-            log.info("PID: {} has stopped", ph.pid());
-        });
-    }
-
-}

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

@@ -5,4 +5,5 @@ This module contains articles about core Java Security
 ### Relevant Articles:
 
 - [Secret Key and String Conversion in Java](https://www.baeldung.com/java-secret-key-to-string)
+- [Enabling Unlimited Strength Cryptography in Java](https://www.baeldung.com/jce-enable-unlimited-strength)
 - More articles: [[<-- prev]](/core-java-modules/core-java-security-2)

core-java-modules/core-java-security-3/src/test/java/com/baeldung/cryptography/CryptographyStrengthUnitTest.java

@@ -0,0 +1,17 @@
+package com.baeldung.cryptography;
+
+import org.junit.Test;
+
+import java.security.NoSuchAlgorithmException;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class CryptographyStrengthUnitTest {
+    private static final int UNLIMITED_KEY_SIZE = 2147483647;
+
+    @Test
+    public void whenDefaultCheck_thenUnlimitedReturned() throws NoSuchAlgorithmException {
+        int maxKeySize = javax.crypto.Cipher.getMaxAllowedKeyLength("AES");
+        assertThat(maxKeySize).isEqualTo(UNLIMITED_KEY_SIZE);
+    }
+}

deeplearning4j/pom.xml

@@ -39,12 +39,12 @@
         <dependency>
             <groupId>org.slf4j</groupId>
             <artifactId>slf4j-api</artifactId>
-            <version>${slf4j.version}</version>
+            <version>${org.slf4j.version}</version>
         </dependency>
         <dependency>
             <groupId>org.slf4j</groupId>
             <artifactId>slf4j-log4j12</artifactId>
-            <version>${slf4j.version}</version>
+            <version>${org.slf4j.version}</version>
         </dependency>
         <!-- https://mvnrepository.com/artifact/org.datavec/datavec-api -->
         <dependency>
@@ -62,7 +62,6 @@
     <properties>
         <dl4j.version>0.9.1</dl4j.version> <!-- Latest non beta version -->
         <httpclient.version>4.3.5</httpclient.version>
-        <slf4j.version>1.7.5</slf4j.version>
     </properties>
 
 </project>

ethereum/pom.xml

@@ -99,7 +99,7 @@
         <dependency>
             <groupId>org.slf4j</groupId>
             <artifactId>jcl-over-slf4j</artifactId>
-            <version>${slf4j.version}</version>
+            <version>${org.slf4j.version}</version>
         </dependency>
         <dependency>
             <groupId>ch.qos.logback</groupId>
@@ -204,8 +204,6 @@
         <spring.boot.version>1.5.6.RELEASE</spring.boot.version>
         <mockito.version>2.21.0</mockito.version>
         <jsonpath.version>2.4.0</jsonpath.version>
-        <logback.version>1.2.3</logback.version>
-        <slf4j.version>1.7.25</slf4j.version>
         <spring-boot-maven-plugin.version>2.0.4.RELEASE</spring-boot-maven-plugin.version>
         <compiler.plugin.version>3.1</compiler.plugin.version>
     </properties>

jackson-modules/jackson-conversions-2/pom.xml

@@ -24,7 +24,7 @@
         <dependency>
             <groupId>com.fasterxml.jackson.datatype</groupId>
             <artifactId>jackson-datatype-jsr310</artifactId>
-            <version>${jackson-datatype.version}</version>
+            <version>${jackson.version}</version>
         </dependency>
         <!-- CSV -->
         <dependency>
@@ -52,7 +52,6 @@
 
     <properties>
         <assertj.version>3.11.0</assertj.version>
-        <jackson-datatype.version>2.9.8</jackson-datatype.version>
     </properties>
 
 </project>

jackson-modules/jackson/src/test/java/com/baeldung/jackson/inheritance/SubTypeHandlingUnitTest.java

@@ -1,14 +1,22 @@
 package com.baeldung.jackson.inheritance;
 
+import static org.hamcrest.CoreMatchers.instanceOf;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThat;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
 
 import org.junit.Test;
 
-import java.util.List;
+import com.baeldung.jackson.inheritance.SubTypeConstructorStructure.Car;
-import java.util.ArrayList;
+import com.baeldung.jackson.inheritance.SubTypeConstructorStructure.Fleet;
-import java.io.IOException;
+import com.baeldung.jackson.inheritance.SubTypeConstructorStructure.Truck;
-
+import com.baeldung.jackson.inheritance.SubTypeConstructorStructure.Vehicle;
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.jsontype.BasicPolymorphicTypeValidator;
+import com.fasterxml.jackson.databind.jsontype.PolymorphicTypeValidator;
 
 public class SubTypeHandlingUnitTest {
     @Test
@@ -23,21 +31,30 @@ public class SubTypeHandlingUnitTest {
     }
 
     @Test
-    public void givenSubType_whenNotUsingNoArgsConstructors_thenSucceed() throws IOException {
+    public void givenSubType_whenNotUsingNoArgsConstructors_thenSucceed() throws IOException {        
         ObjectMapper mapper = new ObjectMapper();
-        mapper.enableDefaultTyping();
+        PolymorphicTypeValidator ptv = BasicPolymorphicTypeValidator.builder()
+            .allowIfSubType("com.baeldung.jackson.inheritance")
+            .allowIfSubType("java.util.ArrayList")
+            .build();
+        mapper.activateDefaultTyping(ptv, ObjectMapper.DefaultTyping.NON_FINAL);
+        
+        Car car = new Car("Mercedes-Benz", "S500", 5, 250.0);
+        Truck truck = new Truck("Isuzu", "NQR", 7500.0);
 
-        SubTypeConstructorStructure.Car car = new SubTypeConstructorStructure.Car("Mercedes-Benz", "S500", 5, 250.0);
+        List<Vehicle> vehicles = new ArrayList<>();
-        SubTypeConstructorStructure.Truck truck = new SubTypeConstructorStructure.Truck("Isuzu", "NQR", 7500.0);
-
-        List<SubTypeConstructorStructure.Vehicle> vehicles = new ArrayList<>();
         vehicles.add(car);
         vehicles.add(truck);
 
-        SubTypeConstructorStructure.Fleet serializedFleet = new SubTypeConstructorStructure.Fleet();
+        Fleet serializedFleet = new Fleet();
         serializedFleet.setVehicles(vehicles);
 
         String jsonDataString = mapper.writeValueAsString(serializedFleet);
-        mapper.readValue(jsonDataString, SubTypeConstructorStructure.Fleet.class);
+        mapper.readValue(jsonDataString, Fleet.class);
+
+        Fleet deserializedFleet = mapper.readValue(jsonDataString, Fleet.class);
+
+        assertThat(deserializedFleet.getVehicles().get(0), instanceOf(Car.class));
+        assertThat(deserializedFleet.getVehicles().get(1), instanceOf(Truck.class));
     }
 }

jackson-modules/jackson/src/test/java/com/baeldung/jackson/inheritance/TypeInfoInclusionUnitTest.java

@@ -10,12 +10,18 @@ import java.util.ArrayList;
 import java.io.IOException;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.jsontype.BasicPolymorphicTypeValidator;
+import com.fasterxml.jackson.databind.jsontype.PolymorphicTypeValidator;
 
 public class TypeInfoInclusionUnitTest {
     @Test
     public void givenTypeInfo_whenAnnotatingGlobally_thenTypesAreCorrectlyRecovered() throws IOException {
         ObjectMapper mapper = new ObjectMapper();
-        mapper.enableDefaultTyping();
+        PolymorphicTypeValidator ptv = BasicPolymorphicTypeValidator.builder()
+            .allowIfSubType("com.baeldung.jackson.inheritance")
+            .allowIfSubType("java.util.ArrayList")
+            .build();
+        mapper.activateDefaultTyping(ptv, ObjectMapper.DefaultTyping.NON_FINAL);
 
         TypeInfoStructure.Car car = new TypeInfoStructure.Car("Mercedes-Benz", "S500", 5, 250.0);
         TypeInfoStructure.Truck truck = new TypeInfoStructure.Truck("Isuzu", "NQR", 7500.0);

json-2/README.md

@@ -7,3 +7,4 @@ This module contains articles about JSON.
 - [Introduction to Jsoniter](https://www.baeldung.com/java-jsoniter)
 - [Introduction to Moshi Json](https://www.baeldung.com/java-json-moshi)
 - [Hypermedia Serialization With JSON-LD](https://www.baeldung.com/json-linked-data)
+- [Generate a Java Class From JSON](https://www.baeldung.com/java-generate-class-from-json)

json-2/src/main/java/com/baeldung/jsontojavaclass/JsonToJavaClassConversion.java

@@ -17,7 +17,22 @@ import com.sun.codemodel.JCodeModel;
 
 public class JsonToJavaClassConversion {
 
-    public Object convertJsonToJavaClass(URL inputJson, File outputJavaClassDirectory, String packageName, String className) throws IOException {
+    public static void main(String[] args) {
+        String packageName = "com.baeldung.jsontojavaclass.pojo";
+        String basePath = "src/main/resources";
+        File inputJson = new File(basePath + File.separator + "input.json");
+        File outputPojoDirectory = new File(basePath + File.separator + "convertedPojo");
+        outputPojoDirectory.mkdirs();
+        try {
+            new JsonToJavaClassConversion().convertJsonToJavaClass(inputJson.toURI().toURL(), outputPojoDirectory, packageName, inputJson.getName().replace(".json", ""));
+        } catch (IOException e) {
+            System.out.println("Encountered issue while converting to pojo: " + e.getMessage());
+            e.printStackTrace();
+        }
+    }
+
+
+    public void convertJsonToJavaClass(URL inputJsonUrl, File outputJavaClassDirectory, String packageName, String javaClassName) throws IOException {
         JCodeModel jcodeModel = new JCodeModel();
 
         GenerationConfig config = new DefaultGenerationConfig() {
@@ -33,10 +48,9 @@ public class JsonToJavaClassConversion {
         };
 
         SchemaMapper mapper = new SchemaMapper(new RuleFactory(config, new Jackson2Annotator(config), new SchemaStore()), new SchemaGenerator());
-        mapper.generate(jcodeModel, className, packageName, inputJson);
+        mapper.generate(jcodeModel, javaClassName, packageName, inputJsonUrl);
 
         jcodeModel.build(outputJavaClassDirectory);
-        return mapper;
     }
 
 }

json-2/src/main/java/com/baeldung/jsontojavaclass/pojo/SamplePojo.java

@@ -5,9 +5,7 @@ import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-
 import javax.annotation.Generated;
-
 import com.fasterxml.jackson.annotation.JsonAnyGetter;
 import com.fasterxml.jackson.annotation.JsonAnySetter;
 import com.fasterxml.jackson.annotation.JsonIgnore;
@@ -16,7 +14,14 @@ import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonPropertyOrder;
 
 @JsonInclude(JsonInclude.Include.NON_NULL)
-@JsonPropertyOrder({ "name", "area", "author", "id", "salary", "topics" })
+@JsonPropertyOrder({
+    "name",
+    "area",
+    "author",
+    "id",
+    "salary",
+    "topics"
+})
 @Generated("jsonschema2pojo")
 public class SamplePojo {
 
@@ -143,40 +148,37 @@ public class SamplePojo {
     @Override
     public String toString() {
         StringBuilder sb = new StringBuilder();
-        sb.append(SamplePojo.class.getName())
+        sb.append(SamplePojo.class.getName()).append('@').append(Integer.toHexString(System.identityHashCode(this))).append('[');
-            .append('@')
-            .append(Integer.toHexString(System.identityHashCode(this)))
-            .append('[');
         sb.append("name");
         sb.append('=');
-        sb.append(((this.name == null) ? "<null>" : this.name));
+        sb.append(((this.name == null)?"<null>":this.name));
         sb.append(',');
         sb.append("area");
         sb.append('=');
-        sb.append(((this.area == null) ? "<null>" : this.area));
+        sb.append(((this.area == null)?"<null>":this.area));
         sb.append(',');
         sb.append("author");
         sb.append('=');
-        sb.append(((this.author == null) ? "<null>" : this.author));
+        sb.append(((this.author == null)?"<null>":this.author));
         sb.append(',');
         sb.append("id");
         sb.append('=');
-        sb.append(((this.id == null) ? "<null>" : this.id));
+        sb.append(((this.id == null)?"<null>":this.id));
         sb.append(',');
         sb.append("salary");
         sb.append('=');
-        sb.append(((this.salary == null) ? "<null>" : this.salary));
+        sb.append(((this.salary == null)?"<null>":this.salary));
         sb.append(',');
         sb.append("topics");
         sb.append('=');
-        sb.append(((this.topics == null) ? "<null>" : this.topics));
+        sb.append(((this.topics == null)?"<null>":this.topics));
         sb.append(',');
         sb.append("additionalProperties");
         sb.append('=');
-        sb.append(((this.additionalProperties == null) ? "<null>" : this.additionalProperties));
+        sb.append(((this.additionalProperties == null)?"<null>":this.additionalProperties));
         sb.append(',');
-        if (sb.charAt((sb.length() - 1)) == ',') {
+        if (sb.charAt((sb.length()- 1)) == ',') {
-            sb.setCharAt((sb.length() - 1), ']');
+            sb.setCharAt((sb.length()- 1), ']');
         } else {
             sb.append(']');
         }
@@ -186,13 +188,13 @@ public class SamplePojo {
     @Override
     public int hashCode() {
         int result = 1;
-        result = ((result * 31) + ((this.area == null) ? 0 : this.area.hashCode()));
+        result = ((result* 31)+((this.area == null)? 0 :this.area.hashCode()));
-        result = ((result * 31) + ((this.author == null) ? 0 : this.author.hashCode()));
+        result = ((result* 31)+((this.author == null)? 0 :this.author.hashCode()));
-        result = ((result * 31) + ((this.topics == null) ? 0 : this.topics.hashCode()));
+        result = ((result* 31)+((this.topics == null)? 0 :this.topics.hashCode()));
-        result = ((result * 31) + ((this.name == null) ? 0 : this.name.hashCode()));
+        result = ((result* 31)+((this.name == null)? 0 :this.name.hashCode()));
-        result = ((result * 31) + ((this.id == null) ? 0 : this.id.hashCode()));
+        result = ((result* 31)+((this.id == null)? 0 :this.id.hashCode()));
-        result = ((result * 31) + ((this.additionalProperties == null) ? 0 : this.additionalProperties.hashCode()));
+        result = ((result* 31)+((this.additionalProperties == null)? 0 :this.additionalProperties.hashCode()));
-        result = ((result * 31) + ((this.salary == null) ? 0 : this.salary.hashCode()));
+        result = ((result* 31)+((this.salary == null)? 0 :this.salary.hashCode()));
         return result;
     }
 
@@ -205,10 +207,7 @@ public class SamplePojo {
             return false;
         }
         SamplePojo rhs = ((SamplePojo) other);
-        return ((((((((this.area == rhs.area) || ((this.area != null) && this.area.equals(rhs.area))) && ((this.author == rhs.author) || ((this.author != null) && this.author.equals(rhs.author))))
+        return ((((((((this.area == rhs.area)||((this.area!= null)&&this.area.equals(rhs.area)))&&((this.author == rhs.author)||((this.author!= null)&&this.author.equals(rhs.author))))&&((this.topics == rhs.topics)||((this.topics!= null)&&this.topics.equals(rhs.topics))))&&((this.name == rhs.name)||((this.name!= null)&&this.name.equals(rhs.name))))&&((this.id == rhs.id)||((this.id!= null)&&this.id.equals(rhs.id))))&&((this.additionalProperties == rhs.additionalProperties)||((this.additionalProperties!= null)&&this.additionalProperties.equals(rhs.additionalProperties))))&&((this.salary == rhs.salary)||((this.salary!= null)&&this.salary.equals(rhs.salary))));
-            && ((this.topics == rhs.topics) || ((this.topics != null) && this.topics.equals(rhs.topics)))) && ((this.name == rhs.name) || ((this.name != null) && this.name.equals(rhs.name))))
-            && ((this.id == rhs.id) || ((this.id != null) && this.id.equals(rhs.id)))) && ((this.additionalProperties == rhs.additionalProperties) || ((this.additionalProperties != null) && this.additionalProperties.equals(rhs.additionalProperties))))
-            && ((this.salary == rhs.salary) || ((this.salary != null) && this.salary.equals(rhs.salary))));
     }
 
 }

json-2/src/main/resources/convertedPojo/com/baeldung/jsontojavaclass/pojo/Address.java

@@ -0,0 +1,119 @@
+
+package com.baeldung.jsontojavaclass.pojo;
+
+import java.util.HashMap;
+import java.util.Map;
+import javax.annotation.Generated;
+import com.fasterxml.jackson.annotation.JsonAnyGetter;
+import com.fasterxml.jackson.annotation.JsonAnySetter;
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+
+@JsonInclude(JsonInclude.Include.NON_NULL)
+@JsonPropertyOrder({
+    "city",
+    "country"
+})
+@Generated("jsonschema2pojo")
+public class Address {
+
+    @JsonProperty("city")
+    private String city;
+    @JsonProperty("country")
+    private String country;
+    @JsonIgnore
+    private Map<String, Object> additionalProperties = new HashMap<String, Object>();
+
+    @JsonProperty("city")
+    public String getCity() {
+        return city;
+    }
+
+    @JsonProperty("city")
+    public void setCity(String city) {
+        this.city = city;
+    }
+
+    public Address withCity(String city) {
+        this.city = city;
+        return this;
+    }
+
+    @JsonProperty("country")
+    public String getCountry() {
+        return country;
+    }
+
+    @JsonProperty("country")
+    public void setCountry(String country) {
+        this.country = country;
+    }
+
+    public Address withCountry(String country) {
+        this.country = country;
+        return this;
+    }
+
+    @JsonAnyGetter
+    public Map<String, Object> getAdditionalProperties() {
+        return this.additionalProperties;
+    }
+
+    @JsonAnySetter
+    public void setAdditionalProperty(String name, Object value) {
+        this.additionalProperties.put(name, value);
+    }
+
+    public Address withAdditionalProperty(String name, Object value) {
+        this.additionalProperties.put(name, value);
+        return this;
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append(Address.class.getName()).append('@').append(Integer.toHexString(System.identityHashCode(this))).append('[');
+        sb.append("city");
+        sb.append('=');
+        sb.append(((this.city == null)?"<null>":this.city));
+        sb.append(',');
+        sb.append("country");
+        sb.append('=');
+        sb.append(((this.country == null)?"<null>":this.country));
+        sb.append(',');
+        sb.append("additionalProperties");
+        sb.append('=');
+        sb.append(((this.additionalProperties == null)?"<null>":this.additionalProperties));
+        sb.append(',');
+        if (sb.charAt((sb.length()- 1)) == ',') {
+            sb.setCharAt((sb.length()- 1), ']');
+        } else {
+            sb.append(']');
+        }
+        return sb.toString();
+    }
+
+    @Override
+    public int hashCode() {
+        int result = 1;
+        result = ((result* 31)+((this.country == null)? 0 :this.country.hashCode()));
+        result = ((result* 31)+((this.additionalProperties == null)? 0 :this.additionalProperties.hashCode()));
+        result = ((result* 31)+((this.city == null)? 0 :this.city.hashCode()));
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (other == this) {
+            return true;
+        }
+        if ((other instanceof Address) == false) {
+            return false;
+        }
+        Address rhs = ((Address) other);
+        return ((((this.country == rhs.country)||((this.country!= null)&&this.country.equals(rhs.country)))&&((this.additionalProperties == rhs.additionalProperties)||((this.additionalProperties!= null)&&this.additionalProperties.equals(rhs.additionalProperties))))&&((this.city == rhs.city)||((this.city!= null)&&this.city.equals(rhs.city))));
+    }
+
+}

json-2/src/main/resources/convertedPojo/com/baeldung/jsontojavaclass/pojo/Input.java

@@ -0,0 +1,213 @@
+
+package com.baeldung.jsontojavaclass.pojo;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import javax.annotation.Generated;
+import com.fasterxml.jackson.annotation.JsonAnyGetter;
+import com.fasterxml.jackson.annotation.JsonAnySetter;
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+
+@JsonInclude(JsonInclude.Include.NON_NULL)
+@JsonPropertyOrder({
+    "name",
+    "area",
+    "author",
+    "id",
+    "topics",
+    "address"
+})
+@Generated("jsonschema2pojo")
+public class Input {
+
+    @JsonProperty("name")
+    private String name;
+    @JsonProperty("area")
+    private String area;
+    @JsonProperty("author")
+    private String author;
+    @JsonProperty("id")
+    private Integer id;
+    @JsonProperty("topics")
+    private List<String> topics = new ArrayList<String>();
+    @JsonProperty("address")
+    private Address address;
+    @JsonIgnore
+    private Map<String, Object> additionalProperties = new HashMap<String, Object>();
+
+    @JsonProperty("name")
+    public String getName() {
+        return name;
+    }
+
+    @JsonProperty("name")
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public Input withName(String name) {
+        this.name = name;
+        return this;
+    }
+
+    @JsonProperty("area")
+    public String getArea() {
+        return area;
+    }
+
+    @JsonProperty("area")
+    public void setArea(String area) {
+        this.area = area;
+    }
+
+    public Input withArea(String area) {
+        this.area = area;
+        return this;
+    }
+
+    @JsonProperty("author")
+    public String getAuthor() {
+        return author;
+    }
+
+    @JsonProperty("author")
+    public void setAuthor(String author) {
+        this.author = author;
+    }
+
+    public Input withAuthor(String author) {
+        this.author = author;
+        return this;
+    }
+
+    @JsonProperty("id")
+    public Integer getId() {
+        return id;
+    }
+
+    @JsonProperty("id")
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    public Input withId(Integer id) {
+        this.id = id;
+        return this;
+    }
+
+    @JsonProperty("topics")
+    public List<String> getTopics() {
+        return topics;
+    }
+
+    @JsonProperty("topics")
+    public void setTopics(List<String> topics) {
+        this.topics = topics;
+    }
+
+    public Input withTopics(List<String> topics) {
+        this.topics = topics;
+        return this;
+    }
+
+    @JsonProperty("address")
+    public Address getAddress() {
+        return address;
+    }
+
+    @JsonProperty("address")
+    public void setAddress(Address address) {
+        this.address = address;
+    }
+
+    public Input withAddress(Address address) {
+        this.address = address;
+        return this;
+    }
+
+    @JsonAnyGetter
+    public Map<String, Object> getAdditionalProperties() {
+        return this.additionalProperties;
+    }
+
+    @JsonAnySetter
+    public void setAdditionalProperty(String name, Object value) {
+        this.additionalProperties.put(name, value);
+    }
+
+    public Input withAdditionalProperty(String name, Object value) {
+        this.additionalProperties.put(name, value);
+        return this;
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append(Input.class.getName()).append('@').append(Integer.toHexString(System.identityHashCode(this))).append('[');
+        sb.append("name");
+        sb.append('=');
+        sb.append(((this.name == null)?"<null>":this.name));
+        sb.append(',');
+        sb.append("area");
+        sb.append('=');
+        sb.append(((this.area == null)?"<null>":this.area));
+        sb.append(',');
+        sb.append("author");
+        sb.append('=');
+        sb.append(((this.author == null)?"<null>":this.author));
+        sb.append(',');
+        sb.append("id");
+        sb.append('=');
+        sb.append(((this.id == null)?"<null>":this.id));
+        sb.append(',');
+        sb.append("topics");
+        sb.append('=');
+        sb.append(((this.topics == null)?"<null>":this.topics));
+        sb.append(',');
+        sb.append("address");
+        sb.append('=');
+        sb.append(((this.address == null)?"<null>":this.address));
+        sb.append(',');
+        sb.append("additionalProperties");
+        sb.append('=');
+        sb.append(((this.additionalProperties == null)?"<null>":this.additionalProperties));
+        sb.append(',');
+        if (sb.charAt((sb.length()- 1)) == ',') {
+            sb.setCharAt((sb.length()- 1), ']');
+        } else {
+            sb.append(']');
+        }
+        return sb.toString();
+    }
+
+    @Override
+    public int hashCode() {
+        int result = 1;
+        result = ((result* 31)+((this.area == null)? 0 :this.area.hashCode()));
+        result = ((result* 31)+((this.address == null)? 0 :this.address.hashCode()));
+        result = ((result* 31)+((this.author == null)? 0 :this.author.hashCode()));
+        result = ((result* 31)+((this.topics == null)? 0 :this.topics.hashCode()));
+        result = ((result* 31)+((this.name == null)? 0 :this.name.hashCode()));
+        result = ((result* 31)+((this.id == null)? 0 :this.id.hashCode()));
+        result = ((result* 31)+((this.additionalProperties == null)? 0 :this.additionalProperties.hashCode()));
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (other == this) {
+            return true;
+        }
+        if ((other instanceof Input) == false) {
+            return false;
+        }
+        Input rhs = ((Input) other);
+        return ((((((((this.area == rhs.area)||((this.area!= null)&&this.area.equals(rhs.area)))&&((this.address == rhs.address)||((this.address!= null)&&this.address.equals(rhs.address))))&&((this.author == rhs.author)||((this.author!= null)&&this.author.equals(rhs.author))))&&((this.topics == rhs.topics)||((this.topics!= null)&&this.topics.equals(rhs.topics))))&&((this.name == rhs.name)||((this.name!= null)&&this.name.equals(rhs.name))))&&((this.id == rhs.id)||((this.id!= null)&&this.id.equals(rhs.id))))&&((this.additionalProperties == rhs.additionalProperties)||((this.additionalProperties!= null)&&this.additionalProperties.equals(rhs.additionalProperties))));
+    }
+
+}

json-2/src/main/resources/input.json

@@ -0,0 +1,16 @@
+{
+  "name": "Baeldung",
+  "area": "tech blogs",
+  "author": "Eugen",
+  "id": 32134,
+  "topics": [
+    "java",
+    "kotlin",
+    "cs",
+    "linux"
+  ],
+  "address": {
+    "city": "Bucharest",
+    "country": "Romania"
+  }
+}

json-2/src/test/java/com/baeldung/jsontojavaclass/JsonToJavaClassConversionUnitTest.java

@@ -3,6 +3,7 @@ package com.baeldung.jsontojavaclass;
 import java.io.File;
 import java.io.IOException;
 import java.net.MalformedURLException;
+import java.util.Arrays;
 
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
@@ -21,17 +22,16 @@ class JsonToJavaClassConversionUnitTest {
         File inputJson = new File(jsonPath + "sample_input.json");
 
         // create the local directory for generating the Java Class file
-        String outputPath = "src/main/java/";
+        String outputPath = "src/test/resources/";
         File outputJavaClassDirectory = new File(outputPath);
-        outputJavaClassDirectory.mkdirs();
 
-        String className = "SamplePojo";
+        String javaClassName = "SamplePojo";
 
-        Object object = jsonToJavaConversion.convertJsonToJavaClass(inputJson.toURI()
+        jsonToJavaConversion.convertJsonToJavaClass(inputJson.toURI()
-            .toURL(), outputJavaClassDirectory, packageName, className);
+                .toURL(), outputJavaClassDirectory, packageName, javaClassName);
-        System.out.println(object);
 
-        Assertions.assertNotNull(object);
+        File outputJavaClassPath = new File(outputPath + packageName.replace(".", "/"));
+        Assertions.assertTrue(Arrays.stream(outputJavaClassPath.listFiles()).peek(System.out::println).anyMatch(file -> (javaClassName+".java").equalsIgnoreCase(file.getName())));
 
     }
 

json-2/src/test/resources/com/baeldung/jsontojavaclass/pojo/SamplePojo.java

@@ -0,0 +1,213 @@
+
+package com.baeldung.jsontojavaclass.pojo;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import javax.annotation.Generated;
+import com.fasterxml.jackson.annotation.JsonAnyGetter;
+import com.fasterxml.jackson.annotation.JsonAnySetter;
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonPropertyOrder;
+
+@JsonInclude(JsonInclude.Include.NON_NULL)
+@JsonPropertyOrder({
+    "name",
+    "area",
+    "author",
+    "id",
+    "salary",
+    "topics"
+})
+@Generated("jsonschema2pojo")
+public class SamplePojo {
+
+    @JsonProperty("name")
+    private String name;
+    @JsonProperty("area")
+    private String area;
+    @JsonProperty("author")
+    private String author;
+    @JsonProperty("id")
+    private Integer id;
+    @JsonProperty("salary")
+    private Integer salary;
+    @JsonProperty("topics")
+    private List<String> topics = new ArrayList<String>();
+    @JsonIgnore
+    private Map<String, Object> additionalProperties = new HashMap<String, Object>();
+
+    @JsonProperty("name")
+    public String getName() {
+        return name;
+    }
+
+    @JsonProperty("name")
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public SamplePojo withName(String name) {
+        this.name = name;
+        return this;
+    }
+
+    @JsonProperty("area")
+    public String getArea() {
+        return area;
+    }
+
+    @JsonProperty("area")
+    public void setArea(String area) {
+        this.area = area;
+    }
+
+    public SamplePojo withArea(String area) {
+        this.area = area;
+        return this;
+    }
+
+    @JsonProperty("author")
+    public String getAuthor() {
+        return author;
+    }
+
+    @JsonProperty("author")
+    public void setAuthor(String author) {
+        this.author = author;
+    }
+
+    public SamplePojo withAuthor(String author) {
+        this.author = author;
+        return this;
+    }
+
+    @JsonProperty("id")
+    public Integer getId() {
+        return id;
+    }
+
+    @JsonProperty("id")
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    public SamplePojo withId(Integer id) {
+        this.id = id;
+        return this;
+    }
+
+    @JsonProperty("salary")
+    public Integer getSalary() {
+        return salary;
+    }
+
+    @JsonProperty("salary")
+    public void setSalary(Integer salary) {
+        this.salary = salary;
+    }
+
+    public SamplePojo withSalary(Integer salary) {
+        this.salary = salary;
+        return this;
+    }
+
+    @JsonProperty("topics")
+    public List<String> getTopics() {
+        return topics;
+    }
+
+    @JsonProperty("topics")
+    public void setTopics(List<String> topics) {
+        this.topics = topics;
+    }
+
+    public SamplePojo withTopics(List<String> topics) {
+        this.topics = topics;
+        return this;
+    }
+
+    @JsonAnyGetter
+    public Map<String, Object> getAdditionalProperties() {
+        return this.additionalProperties;
+    }
+
+    @JsonAnySetter
+    public void setAdditionalProperty(String name, Object value) {
+        this.additionalProperties.put(name, value);
+    }
+
+    public SamplePojo withAdditionalProperty(String name, Object value) {
+        this.additionalProperties.put(name, value);
+        return this;
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append(SamplePojo.class.getName()).append('@').append(Integer.toHexString(System.identityHashCode(this))).append('[');
+        sb.append("name");
+        sb.append('=');
+        sb.append(((this.name == null)?"<null>":this.name));
+        sb.append(',');
+        sb.append("area");
+        sb.append('=');
+        sb.append(((this.area == null)?"<null>":this.area));
+        sb.append(',');
+        sb.append("author");
+        sb.append('=');
+        sb.append(((this.author == null)?"<null>":this.author));
+        sb.append(',');
+        sb.append("id");
+        sb.append('=');
+        sb.append(((this.id == null)?"<null>":this.id));
+        sb.append(',');
+        sb.append("salary");
+        sb.append('=');
+        sb.append(((this.salary == null)?"<null>":this.salary));
+        sb.append(',');
+        sb.append("topics");
+        sb.append('=');
+        sb.append(((this.topics == null)?"<null>":this.topics));
+        sb.append(',');
+        sb.append("additionalProperties");
+        sb.append('=');
+        sb.append(((this.additionalProperties == null)?"<null>":this.additionalProperties));
+        sb.append(',');
+        if (sb.charAt((sb.length()- 1)) == ',') {
+            sb.setCharAt((sb.length()- 1), ']');
+        } else {
+            sb.append(']');
+        }
+        return sb.toString();
+    }
+
+    @Override
+    public int hashCode() {
+        int result = 1;
+        result = ((result* 31)+((this.area == null)? 0 :this.area.hashCode()));
+        result = ((result* 31)+((this.author == null)? 0 :this.author.hashCode()));
+        result = ((result* 31)+((this.topics == null)? 0 :this.topics.hashCode()));
+        result = ((result* 31)+((this.name == null)? 0 :this.name.hashCode()));
+        result = ((result* 31)+((this.id == null)? 0 :this.id.hashCode()));
+        result = ((result* 31)+((this.additionalProperties == null)? 0 :this.additionalProperties.hashCode()));
+        result = ((result* 31)+((this.salary == null)? 0 :this.salary.hashCode()));
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (other == this) {
+            return true;
+        }
+        if ((other instanceof SamplePojo) == false) {
+            return false;
+        }
+        SamplePojo rhs = ((SamplePojo) other);
+        return ((((((((this.area == rhs.area)||((this.area!= null)&&this.area.equals(rhs.area)))&&((this.author == rhs.author)||((this.author!= null)&&this.author.equals(rhs.author))))&&((this.topics == rhs.topics)||((this.topics!= null)&&this.topics.equals(rhs.topics))))&&((this.name == rhs.name)||((this.name!= null)&&this.name.equals(rhs.name))))&&((this.id == rhs.id)||((this.id!= null)&&this.id.equals(rhs.id))))&&((this.additionalProperties == rhs.additionalProperties)||((this.additionalProperties!= null)&&this.additionalProperties.equals(rhs.additionalProperties))))&&((this.salary == rhs.salary)||((this.salary!= null)&&this.salary.equals(rhs.salary))));
+    }
+
+}