Merge branch 'eugenp:master' into master

algorithms-modules/algorithms-miscellaneous-3/README.md

@@ -10,7 +10,7 @@ This module contains articles about algorithms. Some classes of algorithms, e.g.
 - [Converting Between Roman and Arabic Numerals in Java](https://www.baeldung.com/java-convert-roman-arabic)
 - [Practical Java Examples of the Big O Notation](https://www.baeldung.com/java-algorithm-complexity)
 - [Checking If a List Is Sorted in Java](https://www.baeldung.com/java-check-if-list-sorted)
-- [Checking if a Java Graph has a Cycle](https://www.baeldung.com/java-graph-has-a-cycle)
+- [Checking if a Java Graph Has a Cycle](https://www.baeldung.com/java-graph-has-a-cycle)
 - [A Guide to the Folding Technique in Java](https://www.baeldung.com/folding-hashing-technique)
 - [Creating a Triangle with for Loops in Java](https://www.baeldung.com/java-print-triangle)
 - [The K-Means Clustering Algorithm in Java](https://www.baeldung.com/java-k-means-clustering-algorithm)

algorithms-modules/algorithms-miscellaneous-4/README.md

@@ -5,10 +5,10 @@ This module contains articles about algorithms. Some classes of algorithms, e.g.
 ### Relevant articles:
 
 - [Multi-Swarm Optimization Algorithm in Java](https://www.baeldung.com/java-multi-swarm-algorithm)
-- [Check If a String Contains All The Letters of The Alphabet with Java](https://www.baeldung.com/java-string-contains-all-letters)
+- [Check if a String Contains All the Letters of the Alphabet With Java](https://www.baeldung.com/java-string-contains-all-letters)
 - [Find the Middle Element of a Linked List in Java](https://www.baeldung.com/java-linked-list-middle-element)
 - [Find Substrings That Are Palindromes in Java](https://www.baeldung.com/java-palindrome-substrings)
-- [Find the Longest Substring without Repeating Characters](https://www.baeldung.com/java-longest-substring-without-repeated-characters)
+- [Find the Longest Substring Without Repeating Characters](https://www.baeldung.com/java-longest-substring-without-repeated-characters)
 - [Permutations of an Array in Java](https://www.baeldung.com/java-array-permutations)
 - [Find the Smallest Missing Integer in an Array](https://www.baeldung.com/java-smallest-missing-integer-in-array)
 - [Permutations of a String in Java](https://www.baeldung.com/java-string-permutations)

algorithms-modules/algorithms-miscellaneous-5/README.md

@@ -9,7 +9,7 @@ This module contains articles about algorithms. Some classes of algorithms, e.g.
 - [Reversing a Binary Tree in Java](https://www.baeldung.com/java-reversing-a-binary-tree)
 - [Find If Two Numbers Are Relatively Prime in Java](https://www.baeldung.com/java-two-relatively-prime-numbers)
 - [Knapsack Problem Implementation in Java](https://www.baeldung.com/java-knapsack)
-- [How to Determine if a Binary Tree is Balanced in Java](https://www.baeldung.com/java-balanced-binary-tree)
+- [How to Determine if a Binary Tree Is Balanced in Java](https://www.baeldung.com/java-balanced-binary-tree)
 - [Overview of Combinatorial Problems in Java](https://www.baeldung.com/java-combinatorial-algorithms)
 - [Prim’s Algorithm with a Java Implementation](https://www.baeldung.com/java-prim-algorithm)
 - [Maximum Subarray Problem in Java](https://www.baeldung.com/java-maximum-subarray)

apache-cxf-modules/sse-jaxrs/README.md

@@ -1,3 +1,3 @@
 ### Relevant Articles:
 
-- [Server-Sent Events (SSE) In JAX-RS](https://www.baeldung.com/java-ee-jax-rs-sse)
+- [Server-Sent Events (SSE) in JAX-RS](https://www.baeldung.com/java-ee-jax-rs-sse)

apache-httpclient/pom.xml

@@ -90,6 +90,12 @@
             </exclusions>
         </dependency>
 
+        <dependency>
+            <groupId>org.mock-server</groupId>
+            <artifactId>mockserver-netty</artifactId>
+            <version>${mockserver.version}</version>
+        </dependency>
+
         <dependency>
             <groupId>com.github.tomakehurst</groupId>
             <artifactId>wiremock</artifactId>
@@ -112,6 +118,7 @@
         <!-- util -->
         <httpasyncclient.version>4.1.4</httpasyncclient.version>
         <!-- testing -->
+        <mockserver.version>5.6.1</mockserver.version>
         <wiremock.version>2.5.1</wiremock.version>
         <httpclient.version>4.5.8</httpclient.version> <!-- 4.3.6 --> <!-- 4.4-beta1 -->
         <!-- http client & core 5 -->

apache-httpclient/src/test/java/com/baeldung/httpclient/GetRequestMockServer.java

@@ -0,0 +1,79 @@
+package com.baeldung.httpclient;
+
+import static org.mockserver.integration.ClientAndServer.startClientAndServer;
+import static org.mockserver.matchers.Times.exactly;
+import static org.mockserver.model.HttpRequest.request;
+import static org.mockserver.model.HttpResponse.response;
+
+import java.io.IOException;
+import java.net.ServerSocket;
+import java.net.URISyntaxException;
+
+import org.apache.http.HttpStatus;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.mockserver.client.MockServerClient;
+import org.mockserver.integration.ClientAndServer;
+
+public class GetRequestMockServer {
+
+    public static ClientAndServer mockServer;
+    public static String serviceOneUrl;
+    public static String serviceTwoUrl;
+
+    public static int serverPort;
+
+    public static final String SERVER_ADDRESS = "127.0.0.1";
+    public static final String PATH_ONE = "/test1";
+    public static final String PATH_TWO = "/test2";
+    public static final String METHOD = "GET";
+
+    @BeforeAll
+    static void startServer() throws IOException {
+        serverPort = getFreePort();
+        System.out.println("Free port "+serverPort);
+        serviceOneUrl = "http://" + SERVER_ADDRESS + ":" + serverPort + PATH_ONE;
+        serviceTwoUrl = "http://" + SERVER_ADDRESS + ":" + serverPort + PATH_TWO;
+        mockServer = startClientAndServer(serverPort);
+        mockGetRequest();
+    }
+
+    @AfterAll
+    static void stopServer() {
+        mockServer.stop();
+    }
+
+    private static void mockGetRequest() {
+        new MockServerClient(SERVER_ADDRESS, serverPort)
+          .when(
+            request()
+              .withPath(PATH_ONE)
+              .withMethod(METHOD),
+            exactly(5)
+          )
+          .respond(
+            response()
+              .withStatusCode(HttpStatus.SC_OK)
+              .withBody("{\"status\":\"ok\"}")
+          );
+        new MockServerClient(SERVER_ADDRESS, serverPort)
+          .when(
+            request()
+              .withPath(PATH_TWO)
+              .withMethod(METHOD),
+            exactly(1)
+          )
+          .respond(
+            response()
+              .withStatusCode(HttpStatus.SC_OK)
+              .withBody("{\"status\":\"ok\"}")
+          );
+    }
+
+    private static int getFreePort () throws IOException {
+        try (ServerSocket serverSocket = new ServerSocket(0)) {
+            return serverSocket.getLocalPort();
+        }
+    }
+
+}

apache-httpclient/src/test/java/com/baeldung/httpclient/HttpAsyncClientLiveTest.java

@@ -9,6 +9,7 @@ import java.util.concurrent.Future;
 
 import javax.net.ssl.SSLContext;
 
+import org.apache.hc.client5.http.impl.routing.DefaultProxyRoutePlanner;
 import org.junit.jupiter.api.Test;
 
 import org.apache.hc.client5.http.async.methods.SimpleHttpRequest;
@@ -38,7 +39,7 @@ import org.apache.hc.core5.ssl.SSLContexts;
 import org.apache.hc.core5.ssl.TrustStrategy;
 
 
-class HttpAsyncClientLiveTest {
+class HttpAsyncClientLiveTest extends GetRequestMockServer {
 
     private static final String HOST = "http://www.google.com";
     private static final String HOST_WITH_SSL = "https://mms.nw.ru/";
@@ -55,12 +56,12 @@ class HttpAsyncClientLiveTest {
 
     @Test
     void whenUseHttpAsyncClient_thenCorrect() throws InterruptedException, ExecutionException, IOException {
-        final HttpHost target = new HttpHost(HOST);
+        final HttpHost target = new HttpHost(HOST_WITH_COOKIE);
         final SimpleHttpRequest request = SimpleRequestBuilder.get()
             .setHttpHost(target)
             .build();
 
-        final CloseableHttpAsyncClient client = HttpAsyncClients.createDefault();
+        final CloseableHttpAsyncClient client = HttpAsyncClients.custom().build();
         client.start();
 
 
@@ -102,30 +103,15 @@ class HttpAsyncClientLiveTest {
 
     @Test
     void whenUseProxyWithHttpClient_thenCorrect() throws Exception {
-        final CloseableHttpAsyncClient client = HttpAsyncClients.createDefault();
+        final HttpHost proxy = new HttpHost("127.0.0.1", GetRequestMockServer.serverPort);
+        DefaultProxyRoutePlanner routePlanner = new DefaultProxyRoutePlanner(proxy);
+        final CloseableHttpAsyncClient client = HttpAsyncClients.custom()
+            .setRoutePlanner(routePlanner)
+            .build();
         client.start();
-        final HttpHost proxy = new HttpHost("127.0.0.1", 8080);
-        final RequestConfig config = RequestConfig.custom().setProxy(proxy).build();
+
         final SimpleHttpRequest request = new SimpleHttpRequest("GET" ,HOST_WITH_PROXY);
-        request.setConfig(config);
-        final Future<SimpleHttpResponse> future = client.execute(request, new FutureCallback<>(){
-            @Override
-            public void completed(SimpleHttpResponse response) {
-
-                System.out.println("responseData");
-            }
-
-            @Override
-            public void failed(Exception ex) {
-                System.out.println("Error executing HTTP request: " + ex.getMessage());
-            }
-
-            @Override
-            public void cancelled() {
-                System.out.println("HTTP request execution cancelled");
-            }
-        });
-
+        final Future<SimpleHttpResponse> future = client.execute(request, null);
         final HttpResponse  response = future.get();
         assertThat(response.getCode(), equalTo(200));
         client.close();

apache-httpclient4/src/test/java/com/baeldung/httpclient/GetRequestMockServer.java

@@ -0,0 +1,77 @@
+package com.baeldung.httpclient;
+
+import static org.mockserver.integration.ClientAndServer.startClientAndServer;
+import static org.mockserver.matchers.Times.exactly;
+import static org.mockserver.model.HttpRequest.request;
+import static org.mockserver.model.HttpResponse.response;
+
+import java.io.IOException;
+import java.net.ServerSocket;
+import java.net.URISyntaxException;
+
+import org.apache.http.HttpStatus;
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.mockserver.client.MockServerClient;
+import org.mockserver.integration.ClientAndServer;
+
+public class GetRequestMockServer {
+
+    public static ClientAndServer mockServer;
+    public static String serviceOneUrl;
+    public static String serviceTwoUrl;
+
+    public static int serverPort;
+
+    public static final String SERVER_ADDRESS = "127.0.0.1";
+    public static final String PATH_ONE = "/test1";
+    public static final String PATH_TWO = "/test2";
+    public static final String METHOD = "GET";
+
+    @BeforeAll
+    static void startServer() throws IOException, URISyntaxException {
+        serverPort = getFreePort();
+        serviceOneUrl = "http://" + SERVER_ADDRESS + ":" + serverPort + PATH_ONE;
+        serviceTwoUrl = "http://" + SERVER_ADDRESS + ":" + serverPort + PATH_TWO;
+        mockServer = startClientAndServer(serverPort);
+        mockGetRequest();
+    }
+
+    @AfterAll
+    static void stopServer() {
+        mockServer.stop();
+    }
+
+    private static void mockGetRequest() {
+        new MockServerClient(SERVER_ADDRESS, serverPort)
+            .when(
+                request()
+                    .withPath(PATH_ONE)
+                    .withMethod(METHOD),
+                exactly(5)
+            )
+            .respond(
+                response()
+                    .withStatusCode(HttpStatus.SC_OK)
+                    .withBody("{\"status\":\"ok\"}")
+            );
+        new MockServerClient(SERVER_ADDRESS, serverPort)
+            .when(
+                request()
+                    .withPath(PATH_TWO)
+                    .withMethod(METHOD),
+                exactly(1)
+            )
+            .respond(
+                response()
+                    .withStatusCode(HttpStatus.SC_OK)
+                    .withBody("{\"status\":\"ok\"}")
+            );
+    }
+
+    private static int getFreePort () throws IOException {
+        try (ServerSocket serverSocket = new ServerSocket(0)) {
+            return serverSocket.getLocalPort();
+        }
+    }
+}

apache-httpclient4/src/test/java/com/baeldung/httpclient/HttpAsyncClientV4LiveTest.java

@@ -31,7 +31,8 @@ import org.apache.http.protocol.HttpContext;
 import org.apache.http.ssl.SSLContexts;
 import org.junit.jupiter.api.Test;
 
-class HttpAsyncClientV4LiveTest {
+
+class HttpAsyncClientV4LiveTest extends GetRequestMockServer {
 
     private static final String HOST = "http://www.google.com";
     private static final String HOST_WITH_SSL = "https://mms.nw.ru/";
@@ -87,7 +88,7 @@ class HttpAsyncClientV4LiveTest {
     void whenUseProxyWithHttpClient_thenCorrect() throws Exception {
         final CloseableHttpAsyncClient client = HttpAsyncClients.createDefault();
         client.start();
-        final HttpHost proxy = new HttpHost("127.0.0.1", 8080);
+        final HttpHost proxy = new HttpHost("127.0.0.1", GetRequestMockServer.serverPort);
         final RequestConfig config = RequestConfig.custom().setProxy(proxy).build();
         final HttpGet request = new HttpGet(HOST_WITH_PROXY);
         request.setConfig(config);

apache-kafka-2/README.md

@@ -9,3 +9,5 @@ You can build the project from the command line using: *mvn clean install*, or i
 - [Guide to Check if Apache Kafka Server Is Running](https://www.baeldung.com/apache-kafka-check-server-is-running)
 - [Add Custom Headers to a Kafka Message](https://www.baeldung.com/java-kafka-custom-headers)
 - [Get Last N Messages in Apache Kafka Topic](https://www.baeldung.com/java-apache-kafka-get-last-n-messages)
+- [Is a Key Required as Part of Sending Messages to Kafka?](https://www.baeldung.com/java-kafka-message-key)
+- [Read Data From the Beginning Using Kafka Consumer API](https://www.baeldung.com/java-kafka-consumer-api-read)

apache-poi-2/pom.xml

@@ -1,7 +1,7 @@
 <?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">
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xmlns="http://maven.apache.org/POM/4.0.0"
+         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>apache-poi-2</artifactId>
     <version>0.0.1-SNAPSHOT</version>
@@ -19,10 +19,15 @@
             <artifactId>poi-ooxml</artifactId>
             <version>${poi.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.apache.poi</groupId>
+            <artifactId>poi-scratchpad</artifactId>
+            <version>${poi.version}</version>
+        </dependency>
     </dependencies>
 
     <properties>
-        <poi.version>5.2.0</poi.version>
+        <poi.version>5.2.3</poi.version>
     </properties>
 
 </project>

apache-poi-2/src/main/java/com/baeldung/poi/replacevariables/DocTextReplacer.java

@@ -0,0 +1,38 @@
+package com.baeldung.poi.replacevariables;
+
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+
+import org.apache.poi.hwpf.HWPFDocument;
+import org.apache.poi.hwpf.usermodel.Range;
+import org.apache.poi.poifs.filesystem.POIFSFileSystem;
+
+public class DocTextReplacer {
+
+    public void replaceText() throws IOException {
+        String filePath = getClass().getClassLoader()
+          .getResource("baeldung.doc")
+          .getPath();
+        try (InputStream inputStream = new FileInputStream(filePath); POIFSFileSystem fileSystem = new POIFSFileSystem(inputStream)) {
+            HWPFDocument doc = new HWPFDocument(fileSystem);
+            doc = replaceText(doc, "Baeldung", "Hello");
+            saveFile(filePath, doc);
+            doc.close();
+        }
+    }
+
+    private HWPFDocument replaceText(HWPFDocument doc, String originalText, String updatedText) {
+        Range range = doc.getRange();
+        range.replaceText(originalText, updatedText);
+        return doc;
+    }
+
+    private void saveFile(String filePath, HWPFDocument doc) throws IOException {
+        try (FileOutputStream out = new FileOutputStream(filePath)) {
+            doc.write(out);
+        }
+    }
+
+}

apache-poi-2/src/main/java/com/baeldung/poi/replacevariables/DocxNaiveTextReplacer.java

@@ -0,0 +1,63 @@
+package com.baeldung.poi.replacevariables;
+
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.List;
+
+import org.apache.poi.xwpf.usermodel.XWPFDocument;
+import org.apache.poi.xwpf.usermodel.XWPFParagraph;
+import org.apache.poi.xwpf.usermodel.XWPFRun;
+import org.apache.poi.xwpf.usermodel.XWPFTable;
+import org.apache.poi.xwpf.usermodel.XWPFTableCell;
+import org.apache.poi.xwpf.usermodel.XWPFTableRow;
+
+public class DocxNaiveTextReplacer {
+
+    public void replaceText() throws IOException {
+        String filePath = getClass().getClassLoader()
+          .getResource("baeldung-copy.docx")
+          .getPath();
+        try (InputStream inputStream = new FileInputStream(filePath)) {
+            XWPFDocument doc = new XWPFDocument(inputStream);
+            doc = replaceText(doc, "Baeldung", "Hello");
+            saveFile(filePath, doc);
+            doc.close();
+        }
+    }
+
+    private XWPFDocument replaceText(XWPFDocument doc, String originalText, String updatedText) {
+        replaceTextInParagraphs(doc.getParagraphs(), originalText, updatedText);
+        for (XWPFTable tbl : doc.getTables()) {
+            for (XWPFTableRow row : tbl.getRows()) {
+                for (XWPFTableCell cell : row.getTableCells()) {
+                    replaceTextInParagraphs(cell.getParagraphs(), originalText, updatedText);
+                }
+            }
+        }
+        return doc;
+    }
+
+    private void replaceTextInParagraphs(List<XWPFParagraph> paragraphs, String originalText, String updatedText) {
+        paragraphs.forEach(paragraph -> replaceTextInParagraph(paragraph, originalText, updatedText));
+    }
+
+    private void replaceTextInParagraph(XWPFParagraph paragraph, String originalText, String updatedText) {
+        List<XWPFRun> runs = paragraph.getRuns();
+        for (XWPFRun run : runs) {
+            String text = run.getText(0);
+            if (text != null && text.contains(originalText)) {
+                String updatedRunText = text.replace(originalText, updatedText);
+                run.setText(updatedRunText, 0);
+            }
+        }
+    }
+
+    private void saveFile(String filePath, XWPFDocument doc) throws IOException {
+        try (FileOutputStream out = new FileOutputStream(filePath)) {
+            doc.write(out);
+        }
+    }
+
+}

apache-poi-2/src/main/java/com/baeldung/poi/replacevariables/DocxTextReplacer.java

@@ -0,0 +1,65 @@
+package com.baeldung.poi.replacevariables;
+
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.List;
+import java.util.Objects;
+
+import org.apache.poi.xwpf.usermodel.XWPFDocument;
+import org.apache.poi.xwpf.usermodel.XWPFParagraph;
+import org.apache.poi.xwpf.usermodel.XWPFRun;
+import org.apache.poi.xwpf.usermodel.XWPFTable;
+import org.apache.poi.xwpf.usermodel.XWPFTableCell;
+import org.apache.poi.xwpf.usermodel.XWPFTableRow;
+
+public class DocxTextReplacer {
+
+    public void replaceText() throws IOException {
+        String filePath = getClass().getClassLoader()
+          .getResource("baeldung.docx")
+          .getPath();
+        try (InputStream inputStream = new FileInputStream(filePath)) {
+            XWPFDocument doc = new XWPFDocument(inputStream);
+            doc = replaceText(doc, "Baeldung", "Hello");
+            saveFile(filePath, doc);
+            doc.close();
+        }
+    }
+
+    private XWPFDocument replaceText(XWPFDocument doc, String originalText, String updatedText) {
+        replaceTextInParagraphs(doc.getParagraphs(), originalText, updatedText);
+        for (XWPFTable tbl : doc.getTables()) {
+            for (XWPFTableRow row : tbl.getRows()) {
+                for (XWPFTableCell cell : row.getTableCells()) {
+                    replaceTextInParagraphs(cell.getParagraphs(), originalText, updatedText);
+                }
+            }
+        }
+        return doc;
+    }
+
+    private void replaceTextInParagraphs(List<XWPFParagraph> paragraphs, String originalText, String updatedText) {
+        paragraphs.forEach(paragraph -> replaceTextInParagraph(paragraph, originalText, updatedText));
+    }
+
+    private void replaceTextInParagraph(XWPFParagraph paragraph, String originalText, String updatedText) {
+        String paragraphText = paragraph.getParagraphText();
+        if (paragraphText.contains(originalText)) {
+            String updatedParagraphText = paragraphText.replace(originalText, updatedText);
+            while (paragraph.getRuns().size() > 0) {
+                paragraph.removeRun(0);
+            }
+            XWPFRun newRun = paragraph.createRun();
+            newRun.setText(updatedParagraphText);
+        }
+    }
+
+    private void saveFile(String filePath, XWPFDocument doc) throws IOException {
+        try (FileOutputStream out = new FileOutputStream(filePath)) {
+            doc.write(out);
+        }
+    }
+
+}

apache-poi-2/src/test/java/com/baeldung/poi/replacevariables/DocTextReplacerUnitTest.java

@@ -0,0 +1,31 @@
+package com.baeldung.poi.replacevariables;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.util.Arrays;
+
+import org.apache.poi.hwpf.HWPFDocument;
+import org.apache.poi.hwpf.extractor.WordExtractor;
+import org.junit.jupiter.api.Test;
+
+class DocTextReplacerUnitTest {
+
+    @Test
+    void whenReplaceText_ThenTextReplaced() throws IOException {
+        new DocTextReplacer().replaceText();
+
+        String filePath = getClass().getClassLoader()
+          .getResource("baeldung.doc")
+          .getPath();
+        try (FileInputStream fis = new FileInputStream(filePath); HWPFDocument document = new HWPFDocument(fis); WordExtractor extractor = new WordExtractor(document)) {
+            long occurrencesOfHello = Arrays.stream(extractor.getText()
+                .split("\\s+"))
+              .filter(s -> s.contains("Hello"))
+              .count();
+            assertEquals(5, occurrencesOfHello);
+        }
+    }
+
+}

apache-poi-2/src/test/java/com/baeldung/poi/replacevariables/DocxNaiveTextReplacerUnitTest.java

@@ -0,0 +1,31 @@
+package com.baeldung.poi.replacevariables;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.util.Arrays;
+
+import org.apache.poi.xwpf.extractor.XWPFWordExtractor;
+import org.apache.poi.xwpf.usermodel.XWPFDocument;
+import org.junit.jupiter.api.Test;
+
+class DocxNaiveTextReplacerUnitTest {
+
+    @Test
+    void whenReplaceText_ThenTextReplaced() throws IOException {
+        new DocxNaiveTextReplacer().replaceText();
+
+        String filePath = getClass().getClassLoader()
+          .getResource("baeldung-copy.docx")
+          .getPath();
+        try (FileInputStream fis = new FileInputStream(filePath); XWPFDocument document = new XWPFDocument(fis); XWPFWordExtractor extractor = new XWPFWordExtractor(document)) {
+            long occurrencesOfHello = Arrays.stream(extractor.getText()
+                .split("\\s+"))
+              .filter(s -> s.contains("Hello"))
+              .count();
+            assertTrue(occurrencesOfHello < 5);
+        }
+    }
+
+}

apache-poi-2/src/test/java/com/baeldung/poi/replacevariables/DocxTestReplacerUnitTest.java

@@ -0,0 +1,31 @@
+package com.baeldung.poi.replacevariables;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.util.Arrays;
+
+import org.apache.poi.xwpf.extractor.XWPFWordExtractor;
+import org.apache.poi.xwpf.usermodel.XWPFDocument;
+import org.junit.jupiter.api.Test;
+
+class DocxTestReplacerUnitTest {
+
+    @Test
+    void whenReplaceText_ThenTextReplaced() throws IOException {
+        new DocxTextReplacer().replaceText();
+
+        String filePath = getClass().getClassLoader()
+          .getResource("baeldung.docx")
+          .getPath();
+        try (FileInputStream fis = new FileInputStream(filePath); XWPFDocument document = new XWPFDocument(fis); XWPFWordExtractor extractor = new XWPFWordExtractor(document)) {
+            long occurrencesOfHello = Arrays.stream(extractor.getText()
+                .split("\\s+"))
+              .filter(s -> s.contains("Hello"))
+              .count();
+            assertEquals(5, occurrencesOfHello);
+        }
+    }
+
+}

core-java-modules/core-java-arrays-guides/README.md

@@ -5,7 +5,7 @@ This module contains complete guides about arrays in Java
 ### Relevant Articles: 
 - [Arrays in Java: A Reference Guide](https://www.baeldung.com/java-arrays-guide)
 - [Guide to the java.util.Arrays Class](https://www.baeldung.com/java-util-arrays)
-- [What is [Ljava.lang.Object;?](https://www.baeldung.com/java-tostring-array)
+- [What Is [Ljava.lang.Object;?](https://www.baeldung.com/java-tostring-array)
 - [Guide to ArrayStoreException](https://www.baeldung.com/java-arraystoreexception)
 - [Creating a Generic Array in Java](https://www.baeldung.com/java-generic-array)
 - [Maximum Size of Java Arrays](https://www.baeldung.com/java-arrays-max-size)

core-java-modules/core-java-arrays-multidimensional/README.md

@@ -3,5 +3,5 @@
 This module contains articles about multidimensional arrays in Java
 
 ### Relevant Articles: 
-- [Multi-Dimensional Arrays In Java](https://www.baeldung.com/java-jagged-arrays)
-- [Looping Diagonally Through a 2d Java Array](https://www.baeldung.com/java-loop-diagonal-array)
+- [Multi-Dimensional Arrays in Java](https://www.baeldung.com/java-jagged-arrays)
+- [Looping Diagonally Through a 2d Java Array](https://www.baeldung.com/java-loop-diagonal-array)

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

@@ -7,7 +7,7 @@ This module contains articles about advanced operations on arrays in Java. They
 - [How to Copy an Array in Java](https://www.baeldung.com/java-array-copy)
 - [Arrays.deepEquals](https://www.baeldung.com/java-arrays-deepequals)
 - [Find Sum and Average in a Java Array](https://www.baeldung.com/java-array-sum-average)
-- [Intersection Between two Integer Arrays](https://www.baeldung.com/java-array-intersection)
+- [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-collections-2/README.md

@@ -8,7 +8,7 @@
 - [Join and Split Arrays and Collections in Java](https://www.baeldung.com/java-join-and-split)
 - [Java – Combine Multiple Collections](https://www.baeldung.com/java-combine-multiple-collections)
 - [Combining Different Types of Collections in Java](https://www.baeldung.com/java-combine-collections)
-- [Shuffling Collections In Java](https://www.baeldung.com/java-shuffle-collection)
+- [Shuffling Collections in Java](https://www.baeldung.com/java-shuffle-collection)
 - [Sorting in Java](https://www.baeldung.com/java-sorting)
 - [Getting the Size of an Iterable in Java](https://www.baeldung.com/java-iterable-size)
 - [Java Null-Safe Streams from Collections](https://www.baeldung.com/java-null-safe-streams-from-collections)

core-java-modules/core-java-collections-conversions/README.md

@@ -3,7 +3,7 @@
 This module contains articles about conversions among Collection types and arrays in Java.
 
 ### Relevant Articles: 
-- [Converting between an Array and a List in Java](https://www.baeldung.com/convert-array-to-list-and-list-to-array)
+- [Converting Between an Array and a List in Java](https://www.baeldung.com/convert-array-to-list-and-list-to-array)
 - [Converting Between an Array and a Set in Java](https://www.baeldung.com/convert-array-to-set-and-set-to-array)
 - [Convert a Map to an Array, List or Set in Java](https://www.baeldung.com/convert-map-values-to-array-list-set)
 - [Converting a List to String in Java](https://www.baeldung.com/java-list-to-string)

core-java-modules/core-java-collections-list-2/README.md

@@ -3,8 +3,8 @@
 This module contains articles about the Java List collection
 
 ### Relevant Articles: 
-- [Check If Two Lists are Equal in Java](https://www.baeldung.com/java-test-a-list-for-ordinality-and-equality)
-- [Java 8 Streams: Find Items From One List Based On Values From Another List](https://www.baeldung.com/java-streams-find-list-items)
+- [Check if Two Lists Are Equal in Java](https://www.baeldung.com/java-test-a-list-for-ordinality-and-equality)
+- [Java 8 Streams: Find Items From One List Based on Values From Another List](https://www.baeldung.com/java-streams-find-list-items)
 - [A Guide to the Java LinkedList](https://www.baeldung.com/java-linkedlist)
 - [Java List UnsupportedOperationException](https://www.baeldung.com/java-list-unsupported-operation-exception)
 - [Java List Initialization in One Line](https://www.baeldung.com/java-init-list-one-line)

core-java-modules/core-java-collections-list-5/README.md

@@ -7,3 +7,5 @@ This module contains articles about the Java List collection
 - [Finding All Duplicates in a List in Java](https://www.baeldung.com/java-list-find-duplicates)
 - [Moving Items Around in an Arraylist](https://www.baeldung.com/java-arraylist-move-items)
 - [Check if a List Contains an Element From Another List in Java](https://www.baeldung.com/java-check-elements-between-lists)
+- [Array vs. List Performance in Java](https://www.baeldung.com/java-array-vs-list-performance)
+- [Set Default Value for Elements in List](https://www.baeldung.com/java-list-set-default-values)

core-java-modules/core-java-collections-list-5/src/test/java/com/baeldung/java/uniqueelements/UniqueElementsInListUnitTest.java

@@ -0,0 +1,41 @@
+package com.baeldung.java.uniqueelements;
+
+import static java.util.stream.Collectors.toList;
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.LinkedHashSet;
+import java.util.List;
+
+import org.junit.jupiter.api.Test;
+
+public class UniqueElementsInListUnitTest {
+    // @formatter:off
+    private static final List<String> MY_LIST = Arrays.asList(new String[]{
+      "Microsoft Windows",
+      "Mac OS",
+      "GNU Linux",
+      "Free BSD",
+      "GNU Linux",
+      "Mac OS"});
+    // @formatter:on
+
+    @Test
+    void whenConvertToSet_thenGetExpectedResult() {
+        List<String> result = new ArrayList<>(new HashSet<>(MY_LIST));
+        assertThat(result).containsExactlyInAnyOrder("Free BSD", "Microsoft Windows", "Mac OS", "GNU Linux");
+
+        result = new ArrayList<>(new LinkedHashSet<>(MY_LIST));
+        assertThat(result).containsExactly("Microsoft Windows", "Mac OS", "GNU Linux", "Free BSD");
+    }
+
+    @Test
+    void whenUsingStream_thenGetExpectedResult() {
+        List<String> result = MY_LIST.stream()
+          .distinct()
+          .collect(toList());
+        assertThat(result).containsExactly("Microsoft Windows", "Mac OS", "GNU Linux", "Free BSD");
+    }
+}

core-java-modules/core-java-collections-list/README.md

@@ -4,8 +4,8 @@ This module contains articles about the Java List collection
 
 ### Relevant Articles: 
 - [Java – Get Random Item/Element From a List](http://www.baeldung.com/java-random-list-element)
-- [Removing all Nulls from a List in Java](http://www.baeldung.com/java-remove-nulls-from-list)
-- [Removing all duplicates from a List in Java](http://www.baeldung.com/java-remove-duplicates-from-list)
+- [Removing All Nulls From a List in Java](https://www.baeldung.com/java-remove-nulls-from-list)
+- [Removing All Duplicates From a List in Java](https://www.baeldung.com/java-remove-duplicates-from-list)
 - [How to TDD a List Implementation in Java](http://www.baeldung.com/java-test-driven-list)
 - [Iterating Backward Through a List](http://www.baeldung.com/java-list-iterate-backwards)
 - [Remove the First Element from a List](http://www.baeldung.com/java-remove-first-element-from-list)

core-java-modules/core-java-collections-maps-2/README.md

@@ -8,7 +8,7 @@ This module contains articles about Map data structures in Java.
 - [A Guide to Java HashMap](https://www.baeldung.com/java-hashmap)
 - [Guide to WeakHashMap in Java](https://www.baeldung.com/java-weakhashmap)
 - [Map to String Conversion in Java](https://www.baeldung.com/java-map-to-string-conversion)
-- [Iterate over a Map in Java](https://www.baeldung.com/java-iterate-map)
+- [Iterate Over a Map in Java](https://www.baeldung.com/java-iterate-map)
 - [Merging Two Maps with Java 8](https://www.baeldung.com/java-merge-maps)
 - [Sort a HashMap in Java](https://www.baeldung.com/java-hashmap-sort)
 - [Finding the Highest Value in a Java Map](https://www.baeldung.com/java-find-map-max)

core-java-modules/core-java-collections-maps-6/README.md

@@ -1,2 +1,3 @@
 ## Relevant Articles
 - [Copying All Keys and Values From One Hashmap Onto Another Without Replacing Existing Keys and Values](https://www.baeldung.com/java-copy-hashmap-no-changes)
+- [Convert Hashmap to JSON Object in Java](https://www.baeldung.com/java-convert-hashmap-to-json-object)

core-java-modules/core-java-collections-maps-6/src/test/com/baeldung/objecttomap/ObjectToMapUnitTest.java

@@ -0,0 +1,76 @@
+package java.com.baeldung.objecttomap;
+import com.google.gson.Gson;
+import org.junit.Assert;
+import org.junit.Test;
+import wiremock.com.fasterxml.jackson.core.type.TypeReference;
+import wiremock.com.fasterxml.jackson.databind.ObjectMapper;
+import wiremock.com.google.common.reflect.TypeToken;
+import java.lang.reflect.Field;
+import java.util.HashMap;
+import java.util.Map;
+
+public class ObjectToMapUnitTest {
+    Employee employee = new Employee("John", 3000.0);
+
+    @Test
+    public void givenJavaObject_whenUsingReflection_thenConvertToMap() throws IllegalAccessException {
+        Map<String, Object> map = convertUsingReflection(employee);
+        Assert.assertEquals(employee.getName(), map.get("name"));
+        Assert.assertEquals(employee.getSalary(), map.get("salary"));
+    }
+
+    private Map<String, Object> convertUsingReflection(Object object) throws IllegalAccessException {
+        Map<String, Object> map = new HashMap<>();
+        Field[] fields = object.getClass().getDeclaredFields();
+
+        for (Field field : fields) {
+            field.setAccessible(true);
+            map.put(field.getName(), field.get(object));
+        }
+
+        return map;
+    }
+
+    @Test
+    public void givenJavaObject_whenUsingJackson_thenConvertToMap() {
+        ObjectMapper objectMapper = new ObjectMapper();
+        Map<String, Object> map = objectMapper.convertValue(employee, new TypeReference<Map<String, Object>>() {});
+        Assert.assertEquals(employee.getName(), map.get("name"));
+        Assert.assertEquals(employee.getSalary(), map.get("salary"));
+    }
+
+    @Test
+    public void givenJavaObject_whenUsingGson_thenConvertToMap() {
+        Gson gson = new Gson();
+        String json = gson.toJson(employee);
+        Map<String, Object> map = gson.fromJson(json, new TypeToken<Map<String, Object>>() {}.getType());
+        Assert.assertEquals(employee.getName(), map.get("name"));
+        Assert.assertEquals(employee.getSalary(), map.get("salary"));
+    }
+
+    private static class Employee {
+        private String name;
+        private Double salary;
+
+        public Employee(String name, Double salary) {
+            this.name = name;
+            this.salary = salary;
+        }
+
+        public String getName() {
+            return name;
+        }
+
+        public void setName(String name) {
+            this.name = name;
+        }
+
+        public Double getSalary() {
+            return salary;
+        }
+
+        public void setSalary(Double age) {
+            this.salary = salary;
+        }
+    }
+}

core-java-modules/core-java-collections-maps-6/src/test/java/com/baeldung/map/generictypeconversion/ConvertMapWithTypeParamUnitTest.java

@@ -0,0 +1,92 @@
+package com.baeldung.map.generictypeconversion;
+
+import static java.util.stream.Collectors.toMap;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import java.math.BigDecimal;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.junit.jupiter.api.Test;
+
+import com.google.common.collect.Maps;
+
+public class ConvertMapWithTypeParamUnitTest {
+    private static final Map<String, Object> MAP1 = Maps.newHashMap();
+
+    static {
+        MAP1.put("K01", "GNU Linux");
+        MAP1.put("K02", "Mac OS");
+        MAP1.put("K03", "MS Windows");
+    }
+
+    private static final Map<String, String> EXPECTED_MAP1 = Maps.newHashMap();
+
+    static {
+        EXPECTED_MAP1.put("K01", "GNU Linux");
+        EXPECTED_MAP1.put("K02", "Mac OS");
+        EXPECTED_MAP1.put("K03", "MS Windows");
+    }
+
+    private static final Map<String, Object> MAP2 = Maps.newHashMap();
+
+    static {
+        MAP2.put("K01", "GNU Linux");
+        MAP2.put("K02", "Mac OS");
+        MAP2.put("K03", BigDecimal.ONE);
+    }
+
+    private static final Map<String, String> EXPECTED_MAP2_STRING_VALUES = Maps.newHashMap();
+
+    static {
+        EXPECTED_MAP2_STRING_VALUES.put("K01", "GNU Linux");
+        EXPECTED_MAP2_STRING_VALUES.put("K02", "Mac OS");
+        EXPECTED_MAP2_STRING_VALUES.put("K03", "1");
+    }
+
+    @Test
+    void whenCastingToMap_shouldGetExpectedResult() {
+        Map<String, String> result = (Map) MAP1;
+        assertEquals(EXPECTED_MAP1, result);
+
+        Map<String, String> result2 = (Map) MAP2;
+        assertFalse(result2.get("K03") instanceof String);
+    }
+
+    Map<String, String> checkAndTransform(Map<String, Object> inputMap) {
+        Map<String, String> result = new HashMap<>();
+        for (Map.Entry<String, Object> entry : inputMap.entrySet()) {
+            try {
+                result.put(entry.getKey(), (String) entry.getValue());
+            } catch (ClassCastException e) {
+                throw e;
+            }
+        }
+        return result;
+    }
+
+    @Test
+    void whenCheckAndTransform_shouldGetExpectedResult() {
+        Map<String, String> result = checkAndTransform(MAP1);
+        assertEquals(EXPECTED_MAP1, result);
+
+        assertThrows(ClassCastException.class, () -> checkAndTransform(MAP2));
+    }
+
+    @Test
+    void whenUsingStringValueOf_shouldGetExpectedResult() {
+        Map<String, String> result = MAP1.entrySet()
+          .stream()
+          .collect(toMap(Map.Entry::getKey, e -> String.valueOf(e.getValue())));
+
+        assertEquals(EXPECTED_MAP1, result);
+
+        Map<String, String> result2 = MAP2.entrySet()
+          .stream()
+          .collect(toMap(Map.Entry::getKey, e -> String.valueOf(e.getValue())));
+
+        assertEquals(EXPECTED_MAP2_STRING_VALUES, result2);
+    }
+}

core-java-modules/core-java-concurrency-advanced-3/README.md

@@ -15,5 +15,5 @@ This module contains articles about advanced topics about multithreading with co
 - [The ABA Problem in Concurrency](https://www.baeldung.com/cs/aba-concurrency)
 - [Introduction to Lock-Free Data Structures with Java Examples](https://www.baeldung.com/lock-free-programming)
 - [Introduction to Exchanger in Java](https://www.baeldung.com/java-exchanger)
-- [Why Not To Start A Thread In The Constructor?](https://www.baeldung.com/java-thread-constructor)
+- [Why Not to Start a Thread in the Constructor?](https://www.baeldung.com/java-thread-constructor)
 - [[<-- previous]](/core-java-modules/core-java-concurrency-advanced-2)

core-java-modules/core-java-concurrency-basic-2/README.md

@@ -7,7 +7,7 @@ This module contains articles about basic Java concurrency
 - [How to Delay Code Execution in Java](https://www.baeldung.com/java-delay-code-execution)
 - [Difference Between Wait and Sleep in Java](https://www.baeldung.com/java-wait-and-sleep)
 - [Guide to AtomicMarkableReference](https://www.baeldung.com/java-atomicmarkablereference)
-- [Why are Local Variables Thread-Safe in Java](https://www.baeldung.com/java-local-variables-thread-safe)
+- [Why Are Local Variables Thread-Safe in Java](https://www.baeldung.com/java-local-variables-thread-safe)
 - [How to Stop Execution After a Certain Time in Java](https://www.baeldung.com/java-stop-execution-after-certain-time)
 - [How to Get the Number of Threads in a Java Process](https://www.baeldung.com/java-get-number-of-threads)
 - [Set the Name of a Thread in Java](https://www.baeldung.com/java-set-thread-name)

core-java-modules/core-java-concurrency-basic-3/src/main/java/com/baeldung/concurrent/threadreturnvalue/task/FactorialCalculator.java

@@ -0,0 +1,29 @@
+package com.baeldung.concurrent.threadreturnvalue.task;
+
+import java.math.BigInteger;
+
+public class FactorialCalculator {
+
+    public static BigInteger factorial(BigInteger end) {
+        BigInteger start = BigInteger.ONE;
+        BigInteger res = BigInteger.ONE;
+
+        for (int i = start.add(BigInteger.ONE)
+          .intValue(); i <= end.intValue(); i++) {
+            res = res.multiply(BigInteger.valueOf(i));
+        }
+
+        return res;
+    }
+
+    public static BigInteger factorial(BigInteger start, BigInteger end) {
+        BigInteger res = start;
+
+        for (int i = start.add(BigInteger.ONE)
+          .intValue(); i <= end.intValue(); i++) {
+            res = res.multiply(BigInteger.valueOf(i));
+        }
+
+        return res;
+    }
+}

core-java-modules/core-java-concurrency-basic-3/src/main/java/com/baeldung/concurrent/threadreturnvalue/task/callable/CallableExecutor.java

@@ -0,0 +1,38 @@
+package com.baeldung.concurrent.threadreturnvalue.task.callable;
+
+import java.math.BigInteger;
+import java.util.List;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+
+public class CallableExecutor {
+
+    public BigInteger execute(List<CallableFactorialTask> tasks) {
+
+        BigInteger result = BigInteger.ZERO;
+
+        ExecutorService cachedPool = Executors.newCachedThreadPool();
+
+        List<Future<BigInteger>> futures;
+
+        try {
+            futures = cachedPool.invokeAll(tasks);
+        } catch (InterruptedException e) {
+            // exception handling example
+            throw new RuntimeException(e);
+        }
+
+        for (Future<BigInteger> future : futures) {
+            try {
+                result = result.add(future.get());
+            } catch (InterruptedException | ExecutionException e) {
+                // exception handling example
+                throw new RuntimeException(e);
+            }
+        }
+
+        return result;
+    }
+}

core-java-modules/core-java-concurrency-basic-3/src/main/java/com/baeldung/concurrent/threadreturnvalue/task/callable/CallableFactorialTask.java

@@ -0,0 +1,20 @@
+package com.baeldung.concurrent.threadreturnvalue.task.callable;
+
+import static com.baeldung.concurrent.threadreturnvalue.task.FactorialCalculator.factorial;
+
+import java.math.BigInteger;
+import java.util.concurrent.Callable;
+
+public class CallableFactorialTask implements Callable<BigInteger> {
+
+    private final Integer value;
+
+    public CallableFactorialTask(int value) {
+        this.value = value;
+    }
+
+    @Override
+    public BigInteger call() {
+        return factorial(BigInteger.valueOf(value));
+    }
+}

core-java-modules/core-java-concurrency-basic-3/src/main/java/com/baeldung/concurrent/threadreturnvalue/task/fork/ForkExecutor.java

@@ -0,0 +1,34 @@
+package com.baeldung.concurrent.threadreturnvalue.task.fork;
+
+import java.math.BigInteger;
+import java.util.List;
+import java.util.concurrent.Callable;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ForkJoinPool;
+import java.util.concurrent.Future;
+
+public class ForkExecutor {
+
+    private final ForkJoinPool forkJoinPool = ForkJoinPool.commonPool();
+
+    public BigInteger execute(ForkFactorialTask forkFactorial) {
+        return forkJoinPool.invoke(forkFactorial);
+    }
+
+    public BigInteger execute(List<Callable<BigInteger>> forkFactorials) {
+        List<Future<BigInteger>> futures = forkJoinPool.invokeAll(forkFactorials);
+
+        BigInteger result = BigInteger.ZERO;
+
+        for (Future<BigInteger> future : futures) {
+            try {
+                result = result.add(future.get());
+            } catch (InterruptedException | ExecutionException e) {
+                // exception handling example
+                throw new RuntimeException(e);
+            }
+        }
+
+        return result;
+    }
+}

core-java-modules/core-java-concurrency-basic-3/src/main/java/com/baeldung/concurrent/threadreturnvalue/task/fork/ForkFactorialTask.java

@@ -0,0 +1,43 @@
+package com.baeldung.concurrent.threadreturnvalue.task.fork;
+
+import static com.baeldung.concurrent.threadreturnvalue.task.FactorialCalculator.factorial;
+
+import java.math.BigInteger;
+import java.util.concurrent.RecursiveTask;
+
+public class ForkFactorialTask extends RecursiveTask<BigInteger> {
+
+    private final int start;
+    private final int end;
+    private final int threshold;
+
+    public ForkFactorialTask(int end, int threshold) {
+        this.start = 1;
+        this.end = end;
+        this.threshold = threshold;
+    }
+
+    public ForkFactorialTask(int start, int end, int threshold) {
+        this.start = start;
+        this.end = end;
+        this.threshold = threshold;
+    }
+
+    @Override
+    protected BigInteger compute() {
+
+        BigInteger sum = BigInteger.ONE;
+
+        if (end - start > threshold) {
+
+            int middle = (end + start) / 2;
+
+            return sum.multiply(new ForkFactorialTask(start, middle, threshold).fork()
+              .join()
+              .multiply(new ForkFactorialTask(middle + 1, end, threshold).fork()
+                .join()));
+        }
+
+        return sum.multiply(factorial(BigInteger.valueOf(start), BigInteger.valueOf(end)));
+    }
+}

core-java-modules/core-java-concurrency-basic-3/src/test/java/com/baeldung/concurrent/threadreturnvalue/callable/CallableUnitTest.java

@@ -0,0 +1,22 @@
+package com.baeldung.concurrent.threadreturnvalue.callable;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.math.BigInteger;
+import java.util.Arrays;
+
+import org.junit.jupiter.api.Test;
+
+import com.baeldung.concurrent.threadreturnvalue.task.callable.CallableExecutor;
+import com.baeldung.concurrent.threadreturnvalue.task.callable.CallableFactorialTask;
+
+public class CallableUnitTest {
+
+    private final CallableExecutor callableExecutor = new CallableExecutor();
+
+    @Test
+    void givenCallableExecutor_whenExecuteFactorial_thenResultOk() {
+        BigInteger result = callableExecutor.execute(Arrays.asList(new CallableFactorialTask(5), new CallableFactorialTask(3)));
+        assertEquals(BigInteger.valueOf(126), result);
+    }
+}

core-java-modules/core-java-concurrency-basic-3/src/test/java/com/baeldung/concurrent/threadreturnvalue/completableFuture/CompletableFutureUnitTest.java

@@ -0,0 +1,39 @@
+package com.baeldung.concurrent.threadreturnvalue.completableFuture;
+
+import static com.baeldung.concurrent.threadreturnvalue.task.FactorialCalculator.factorial;
+import static java.util.concurrent.CompletableFuture.allOf;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.math.BigInteger;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Executors;
+
+import org.junit.jupiter.api.Test;
+
+public class CompletableFutureUnitTest {
+
+    @Test
+    void givenCompletableFuture_whenSupplyAsyncFactorial_thenResultOk() throws ExecutionException, InterruptedException {
+        CompletableFuture<BigInteger> completableFuture = CompletableFuture.supplyAsync(() -> factorial(BigInteger.valueOf(10)));
+        assertEquals(BigInteger.valueOf(3628800), completableFuture.get());
+    }
+
+    @Test
+    void givenCompletableFuture_whenComposeTasks_thenResultOk() throws ExecutionException, InterruptedException {
+        CompletableFuture<BigInteger> completableFuture = CompletableFuture.supplyAsync(() -> factorial(BigInteger.valueOf(3)))
+          .thenCompose(inputFromFirstTask -> CompletableFuture.supplyAsync(() -> factorial(inputFromFirstTask)));
+        assertEquals(BigInteger.valueOf(720), completableFuture.get());
+    }
+
+    @Test
+    void givenCompletableFuture_whenAllOfTasks_thenResultOk() {
+        CompletableFuture<BigInteger> asyncTask1 = CompletableFuture.supplyAsync(() -> BigInteger.valueOf(5));
+        CompletableFuture<String> asyncTask2 = CompletableFuture.supplyAsync(() -> "3");
+
+        BigInteger result = allOf(asyncTask1, asyncTask2).thenApplyAsync(fn -> factorial(asyncTask1.join()).add(factorial(new BigInteger(asyncTask2.join()))), Executors.newFixedThreadPool(1))
+          .join();
+
+        assertEquals(BigInteger.valueOf(126), result);
+    }
+}

core-java-modules/core-java-concurrency-basic-3/src/test/java/com/baeldung/concurrent/threadreturnvalue/fork/ForkUnitTest.java

@@ -0,0 +1,27 @@
+package com.baeldung.concurrent.threadreturnvalue.fork;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.math.BigInteger;
+import java.util.Arrays;
+
+import org.junit.jupiter.api.Test;
+
+import com.baeldung.concurrent.threadreturnvalue.task.callable.CallableFactorialTask;
+import com.baeldung.concurrent.threadreturnvalue.task.fork.ForkExecutor;
+import com.baeldung.concurrent.threadreturnvalue.task.fork.ForkFactorialTask;
+
+public class ForkUnitTest {
+
+    private final ForkExecutor forkExecutor = new ForkExecutor();
+
+    @Test
+    void givenForkExecutor_whenExecuteRecursiveTask_thenResultOk() {
+        assertEquals(BigInteger.valueOf(3628800), forkExecutor.execute(new ForkFactorialTask(10, 5)));
+    }
+
+    @Test
+    void givenForkExecutor_whenExecuteCallable_thenResultOk() {
+        assertEquals(BigInteger.valueOf(126), forkExecutor.execute(Arrays.asList(new CallableFactorialTask(5), new CallableFactorialTask(3))));
+    }
+}

core-java-modules/core-java-concurrency-basic/README.md

@@ -9,5 +9,5 @@ This module contains articles about basic Java concurrency
 - [How to Kill a Java Thread](https://www.baeldung.com/java-thread-stop)
 - [ExecutorService – Waiting for Threads to Finish](https://www.baeldung.com/java-executor-wait-for-threads)
 - [Runnable vs. Callable in Java](https://www.baeldung.com/java-runnable-callable)
-- [What is Thread-Safety and How to Achieve it?](https://www.baeldung.com/java-thread-safety)
+- [What Is Thread-Safety and How to Achieve It?](https://www.baeldung.com/java-thread-safety)
 - [[Next -->]](/core-java-modules/core-java-concurrency-basic-2)

core-java-modules/core-java-concurrency-collections/README.md

@@ -7,7 +7,7 @@ This module contains articles about concurrent Java collections
 - [A Guide to ConcurrentMap](http://www.baeldung.com/java-concurrent-map)
 - [Guide to PriorityBlockingQueue in Java](http://www.baeldung.com/java-priority-blocking-queue)
 - [Avoiding the ConcurrentModificationException in Java](http://www.baeldung.com/java-concurrentmodificationexception)
-- [Custom Thread Pools In Java 8 Parallel Streams](http://www.baeldung.com/java-8-parallel-streams-custom-threadpool)
+- [Custom Thread Pools in Java 8 Parallel Streams](https://www.baeldung.com/java-8-parallel-streams-custom-threadpool)
 - [Guide to DelayQueue](http://www.baeldung.com/java-delay-queue)
 - [A Guide to Java SynchronousQueue](http://www.baeldung.com/java-synchronous-queue)
 - [Guide to the ConcurrentSkipListMap](http://www.baeldung.com/java-concurrent-skip-list-map)

core-java-modules/core-java-date-operations-1/README.md

@@ -10,6 +10,6 @@ This module contains articles about date operations in Java.
 - [Handling Daylight Savings Time in Java](http://www.baeldung.com/java-daylight-savings)
 - [Calculate Age in Java](http://www.baeldung.com/java-get-age)
 - [Increment Date in Java](http://www.baeldung.com/java-increment-date)
-- [Add Hours To a Date In Java](http://www.baeldung.com/java-add-hours-date)
+- [Add Hours to a Date in Java](https://www.baeldung.com/java-add-hours-date)
 - [Introduction to Joda-Time](http://www.baeldung.com/joda-time)
-- [[Next -->]](/core-java-modules/core-java-date-operations-2)
+- [[Next -->]](/core-java-modules/core-java-date-operations-2)

core-java-modules/core-java-date-operations-2/README.md

@@ -5,10 +5,10 @@ This module contains articles about date operations in Java.
 
 - [Get the Current Date Prior to Java 8](https://www.baeldung.com/java-get-the-current-date-legacy)
 - [Skipping Weekends While Adding Days to LocalDate in Java 8](https://www.baeldung.com/java-localdate-add-days-skip-weekends)
-- [Checking if Two Java Dates are On the Same Day](https://www.baeldung.com/java-check-two-dates-on-same-day)
+- [Checking if Two Java Dates Are on the Same Day](https://www.baeldung.com/java-check-two-dates-on-same-day)
 - [Converting Java Date to OffsetDateTime](https://www.baeldung.com/java-convert-date-to-offsetdatetime)
 - [How to Set the JVM Time Zone](https://www.baeldung.com/java-jvm-time-zone)
-- [How to determine day of week by passing specific date in Java?](https://www.baeldung.com/java-get-day-of-week)
+- [How to Determine Day of Week by Passing Specific Date in Java?](https://www.baeldung.com/java-get-day-of-week)
 - [Finding Leap Years in Java](https://www.baeldung.com/java-leap-year)
 - [Getting the Week Number From Any Date](https://www.baeldung.com/java-get-week-number)
 - [Subtract Days from a Date in Java](https://www.baeldung.com/java-subtract-days-from-date)

core-java-modules/core-java-datetime-string/README.md

@@ -4,12 +4,12 @@ This module contains articles about parsing and formatting Java date and time ob
 
 ### Relevant Articles: 
 - [Check If a String Is a Valid Date in Java](https://www.baeldung.com/java-string-valid-date)
-- [RegEx for matching Date Pattern in Java](http://www.baeldung.com/java-date-regular-expressions)
+- [Regex for Matching Date Pattern in Java](https://www.baeldung.com/java-date-regular-expressions)
 - [Guide to DateTimeFormatter](https://www.baeldung.com/java-datetimeformatter)
 - [Format ZonedDateTime to String](https://www.baeldung.com/java-format-zoned-datetime-string)
 - [A Guide to SimpleDateFormat](https://www.baeldung.com/java-simple-date-format)
-- [Display All Time Zones With GMT And UTC in Java](http://www.baeldung.com/java-time-zones)
-- [Convert between String and Timestamp](https://www.baeldung.com/java-string-to-timestamp)
+- [Display All Time Zones With GMT and UTC in Java](https://www.baeldung.com/java-time-zones)
+- [Convert Between String and Timestamp](https://www.baeldung.com/java-string-to-timestamp)
 - [Convert String to Date in Java](http://www.baeldung.com/java-string-to-date)
 - [Format a Milliseconds Duration to HH:MM:SS](https://www.baeldung.com/java-ms-to-hhmmss)
 - [Format Instant to String in Java](https://www.baeldung.com/java-instant-to-string)

core-java-modules/core-java-io-apis-2/README.md

@@ -12,3 +12,5 @@ This module contains articles about core Java input/output(IO) APIs.
 - [Storing Java Scanner Input in an Array](https://www.baeldung.com/java-store-scanner-input-in-array)
 - [How to Take Input as String With Spaces in Java Using Scanner?](https://www.baeldung.com/java-scanner-input-with-spaces)
 - [Write Console Output to Text File in Java](https://www.baeldung.com/java-write-console-output-file)
+- [What’s the difference between Scanner next() and nextLine() methods?](https://www.baeldung.com/java-scanner-next-vs-nextline)
+- [Handle NoSuchElementException When Reading a File Through Scanner](https://www.baeldung.com/java-scanner-nosuchelementexception-reading-file)

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

@@ -3,9 +3,9 @@
 This module contains articles about core features in the Java language
 
 ### Relevant Articles: 
-- [Java Primitives versus Objects](https://www.baeldung.com/java-primitives-vs-objects)
+- [Java Primitives Versus Objects](https://www.baeldung.com/java-primitives-vs-objects)
 - [Command-Line Arguments in Java](https://www.baeldung.com/java-command-line-arguments)
-- [What is a POJO Class?](https://www.baeldung.com/java-pojo-class)
+- [What Is a Pojo Class?](baeldung.com/java-pojo-class)
 - [Java Default Parameters Using Method Overloading](https://www.baeldung.com/java-default-parameters-method-overloading)
 - [How to Return Multiple Values From a Java Method](https://www.baeldung.com/java-method-return-multiple-values)
 - [Guide to the Java finally Keyword](https://www.baeldung.com/java-finally-keyword)

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

@@ -4,7 +4,7 @@ This module contains articles about core features in the Java language
 
 - [Class.isInstance vs Class.isAssignableFrom and instanceof](https://www.baeldung.com/java-isinstance-isassignablefrom)
 - [Converting a Java String Into a Boolean](https://www.baeldung.com/java-string-to-boolean)
-- [When are Static Variables Initialized in Java?](https://www.baeldung.com/java-static-variables-initialization)
+- [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)

core-java-modules/core-java-lang-math-2/README.md

@@ -6,7 +6,7 @@
 
 - [Calculate Factorial in Java](https://www.baeldung.com/java-calculate-factorial)
 - [Generate Combinations in Java](https://www.baeldung.com/java-combinations-algorithm)
-- [Check If Two Rectangles Overlap In Java](https://www.baeldung.com/java-check-if-two-rectangles-overlap)
+- [Check if Two Rectangles Overlap in Java](https://www.baeldung.com/java-check-if-two-rectangles-overlap)
 - [Calculate the Distance Between Two Points in Java](https://www.baeldung.com/java-distance-between-two-points)
 - [Find the Intersection of Two Lines in Java](https://www.baeldung.com/java-intersection-of-two-lines)
 - [Round Up to the Nearest Hundred in Java](https://www.baeldung.com/java-round-up-nearest-hundred)

core-java-modules/core-java-lang-oop-types/README.md

@@ -8,7 +8,7 @@ This module contains articles about types in Java
 - [Guide to the this Java Keyword](https://www.baeldung.com/java-this)
 - [Nested Classes in Java](https://www.baeldung.com/java-nested-classes)
 - [Marker Interfaces in Java](https://www.baeldung.com/java-marker-interfaces)
-- [Iterating over Enum Values in Java](https://www.baeldung.com/java-enum-iteration)
+- [Iterating Over Enum Values in Java](https://www.baeldung.com/java-enum-iteration)
 - [Attaching Values to Java Enum](https://www.baeldung.com/java-enum-values)
 - [A Guide to Java Enums](https://www.baeldung.com/a-guide-to-java-enums)
 - [Determine if an Object Is of Primitive Type](https://www.baeldung.com/java-object-primitive-type)

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

@@ -4,7 +4,7 @@ This module contains articles about Java operators
 
 ## Relevant Articles:
 - [Guide to the Diamond Operator in Java](https://www.baeldung.com/java-diamond-operator)
-- [Ternary Operator In Java](https://www.baeldung.com/java-ternary-operator)
+- [Ternary Operator in Java](https://www.baeldung.com/java-ternary-operator)
 - [The Modulo Operator in Java](https://www.baeldung.com/modulo-java)
 - [Java instanceof Operator](https://www.baeldung.com/java-instanceof)
 - [A Guide to Increment and Decrement Unary Operators in Java](https://www.baeldung.com/java-unary-operators)

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

@@ -5,7 +5,7 @@ This module contains articles about core features in the Java language
 ### Relevant Articles: 
 - [Generate equals() and hashCode() with Eclipse](https://www.baeldung.com/java-eclipse-equals-and-hashcode)
 - [Comparator and Comparable in Java](https://www.baeldung.com/java-comparator-comparable)
-- [Recursion In Java](https://www.baeldung.com/java-recursion)
+- [Recursion in Java](https://www.baeldung.com/java-recursion)
 - [A Guide to the finalize Method in Java](https://www.baeldung.com/java-finalize)
 - [Quick Guide to java.lang.System](https://www.baeldung.com/java-lang-system)
 - [Using Java Assertions](https://www.baeldung.com/java-assert)

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

@@ -12,6 +12,6 @@ This module contains articles about networking in Java
 - [Authentication with HttpUrlConnection](https://www.baeldung.com/java-http-url-connection)
 - [Download a File From an URL in Java](https://www.baeldung.com/java-download-file)
 - [Handling java.net.ConnectException](https://www.baeldung.com/java-net-connectexception)
-- [Getting MAC addresses in Java](https://www.baeldung.com/java-mac-address)
+- [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)
 - [[<-- Prev]](/core-java-modules/core-java-networking)

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

@@ -6,12 +6,12 @@ This module contains articles about networking in Java
 
 - [Connecting Through Proxy Servers in Core Java](https://www.baeldung.com/java-connect-via-proxy-server)
 - [Broadcasting and Multicasting in Java](http://www.baeldung.com/java-broadcast-multicast)
-- [A Guide To UDP In Java](http://www.baeldung.com/udp-in-java)
-- [A Guide To HTTP Cookies In Java](http://www.baeldung.com/cookies-java)
+- [A Guide to UDP In Java](https://www.baeldung.com/udp-in-java)
+- [A Guide to HTTP Cookies in Java](https://www.baeldung.com/cookies-java)
 - [A Guide to the Java URL](http://www.baeldung.com/java-url)
 - [Working with Network Interfaces in Java](http://www.baeldung.com/java-network-interfaces)
 - [A Guide to Java Sockets](http://www.baeldung.com/a-guide-to-java-sockets)
 - [Guide to Java URL Encoding/Decoding](http://www.baeldung.com/java-url-encoding-decoding)
-- [Difference between URL and URI](http://www.baeldung.com/java-url-vs-uri)
+- [Difference Between URL and URI](https://www.baeldung.com/java-url-vs-uri)
 - [Read an InputStream using the Java Server Socket](https://www.baeldung.com/java-inputstream-server-socket)
 - [[More -->]](/core-java-modules/core-java-networking-2)

core-java-modules/core-java-reflection-private-constructor/README.md

@@ -1,10 +1 @@
 ### Relevant Articles:
-
-- [Reading the Value of ‘private’ Fields from a Different Class in Java](https://www.baeldung.com/java-reflection-read-private-field-value)
-- [Set Field Value With Reflection](https://www.baeldung.com/java-set-private-field-value)
-- [Checking If a Method is Static Using Reflection in Java](https://www.baeldung.com/java-check-method-is-static)
-- [Checking if a Java Class is ‘abstract’ Using Reflection](https://www.baeldung.com/java-reflection-is-class-abstract)
-- [Invoking a Private Method in Java](https://www.baeldung.com/java-call-private-method)
-- [Finding All Classes in a Java Package](https://www.baeldung.com/java-find-all-classes-in-package)
-- [Invoke a Static Method Using Java Reflection API](https://www.baeldung.com/java-invoke-static-method-reflection)
-- [What Is the JDK com.sun.proxy.$Proxy Class?](https://www.baeldung.com/jdk-com-sun-proxy)

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

@@ -3,7 +3,7 @@
 - [Void Type in Java](https://www.baeldung.com/java-void-type)
 - [Retrieve Fields from a Java Class Using Reflection](https://www.baeldung.com/java-reflection-class-fields)
 - [Method Parameter Reflection in Java](http://www.baeldung.com/java-parameter-reflection)
-- [Changing Annotation Parameters At Runtime](http://www.baeldung.com/java-reflection-change-annotation-params)
+- [Changing Annotation Parameters at Runtime](https://www.baeldung.com/java-reflection-change-annotation-params)
 - [Dynamic Proxies in Java](http://www.baeldung.com/java-dynamic-proxies)
 - [What Causes java.lang.reflect.InvocationTargetException?](https://www.baeldung.com/java-lang-reflect-invocationtargetexception)
 - [How to Get a Name of a Method Being Executed?](http://www.baeldung.com/java-name-of-executing-method)

core-java-modules/core-java-regex-2/src/test/java/com/baeldung/regex/z_regexp/ZRegularExpressionUnitTest.java

@@ -3,33 +3,81 @@ package com.baeldung.regex.z_regexp;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
+import java.util.regex.Pattern;
 public class ZRegularExpressionUnitTest {
     @Test
     public void givenCreditCardNumber_thenReturnIfMatched() {
         String creditCardNumber = "1234567890123456";
+        String creditCardNumber2 = "1234567890123456\n";
         String pattern = "\\d{16}\\z";
-        Assertions.assertTrue(creditCardNumber.matches(pattern));
+        Assertions.assertTrue(Pattern.compile(pattern).matcher(creditCardNumber).find());
+        Assertions.assertFalse(Pattern.compile(pattern).matcher(creditCardNumber2).find());
+    }
+
+    @Test
+    public void givenCreditCardNumber_thenReturnIfNotMatched() {
+        String creditCardNumber = "1234567890123456\n";
+        String pattern = "\\d{16}\\z";
+        Assertions.assertFalse(Pattern.compile(pattern).matcher(creditCardNumber).find());
     }
 
     @Test
     public void givenLogOutput_thenReturnIfMatched() {
         String logLine = "2022-05-01 14:30:00,123 INFO Some log message";
         String pattern = ".*message\\z";
-        Assertions.assertTrue(logLine.matches(pattern));
+        Assertions.assertTrue(Pattern.compile(pattern).matcher(logLine).find());
     }
 
+    @Test
+    public void givenLogOutput_thenReturnIfNotMatched() {
+        String logLine = "2022-05-01 14:30:00,123 INFO Some log message\n";
+        String pattern = ".*message\\z";
+        Assertions.assertFalse(Pattern.compile(pattern).matcher(logLine).find());
+    }
     @Test
     public void givenEmailMessage_thenReturnIfMatched() {
         String myMessage = "Hello HR, I hope i can write to Baeldung\n";
-        String pattern = ".*Baeldung\\s*\\Z";
-        Assertions.assertTrue(myMessage.matches(pattern));
+        String myMessage2 = "Hello HR, I hope\n i can write to Baeldung";
+        String pattern = ".*Baeldung\\Z";
+        String pattern2 = ".*hope\\Z";
+        Assertions.assertTrue(Pattern.compile(pattern).matcher(myMessage).find());
+        Assertions.assertFalse(Pattern.compile(pattern2).matcher(myMessage2).find());
+    }
+
+    @Test
+    public void givenEmailMessage_thenReturnIfNotMatched() {
+        String myMessage = "Hello HR, I hope\n i can write to Baeldung";
+        String pattern = ".*hope\\Z";
+        Assertions.assertFalse(Pattern.compile(pattern).matcher(myMessage).find());
     }
 
     @Test
     public void givenFileExtension_thenReturnIfMatched() {
-        String fileName = "image.jpeg";
+        String fileName = "image.jpeg\n";
+        String fileName2 = "image2.jpeg\n.png";
         String pattern = ".*\\.jpeg\\Z";
-        Assertions.assertTrue(fileName.matches(pattern));
+        Assertions.assertTrue(Pattern.compile(pattern).matcher(fileName).find());
+        Assertions.assertFalse(Pattern.compile(pattern).matcher(fileName2).find());
     }
 
-}
+    @Test
+    public void givenFileExtension_thenReturnIfNotMatched() {
+        String fileName = "image2.jpeg\n.png";
+        String pattern = ".*\\.jpeg\\Z";
+        Assertions.assertFalse(Pattern.compile(pattern).matcher(fileName).find());
+    }
+    @Test
+    public void givenURL_thenReturnIfMatched() {
+        String url = "https://www.example.com/api/endpoint\n";
+        String pattern = ".*/endpoint$";
+        Assertions.assertTrue(Pattern.compile(pattern).matcher(url).find());
+    }
+
+    @Test
+    public void givenSentence_thenReturnIfMatched() {
+        String sentence = "Hello, how are you?";
+        String pattern = ".*[.?!]$";
+        Assertions.assertTrue(Pattern.compile(pattern).matcher(sentence).find());
+    }
+
+}

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

@@ -4,7 +4,7 @@ This module contains articles about core Java Security
 
 ### Relevant Articles:
 
-- [Guide To The Java Authentication And Authorization Service (JAAS)](https://www.baeldung.com/java-authentication-authorization-service)
+- [Guide to the Java Authentication And Authorization Service (JAAS)](https://www.baeldung.com/java-authentication-authorization-service)
 - [MD5 Hashing in Java](http://www.baeldung.com/java-md5)
 - [Hashing a Password in Java](https://www.baeldung.com/java-password-hashing)
 - [SHA-256 and SHA3-256 Hashing in Java](https://www.baeldung.com/sha-256-hashing-java)

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

@@ -6,4 +6,5 @@
 - [Introduction to Java Serialization](http://www.baeldung.com/java-serialization)
 - [Deserialization Vulnerabilities in Java](https://www.baeldung.com/java-deserialization-vulnerabilities)
 - [Serialization Validation in Java](https://www.baeldung.com/java-validate-serializable)
-- [What is the serialVersionUID?](http://www.baeldung.com/java-serial-version-uid)
+- [What Is the serialVersionUID?](https://www.baeldung.com/java-serial-version-uid)
+- [Java Serialization: readObject() vs. readResolve()](https://www.baeldung.com/java-serialization-readobject-vs-readresolve)

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

@@ -12,5 +12,5 @@ This module contains articles about the Stream API in Java.
 - [Java Stream Filter with Lambda Expression](https://www.baeldung.com/java-stream-filter-lambda)
 - [Counting Matches on a Stream Filter](https://www.baeldung.com/java-stream-filter-count)
 - [Summing Numbers with Java Streams](https://www.baeldung.com/java-stream-sum)
-- [How to Find all Getters Returning Null](https://www.baeldung.com/java-getters-returning-null)
+- [How to Find All Getters Returning Null](https://www.baeldung.com/java-getters-returning-null)
 - More articles: [[next -->]](/../core-java-streams-2)

core-java-modules/core-java-string-algorithms-2/README.md

@@ -6,7 +6,7 @@ This module contains articles about string-related algorithms.
 - [How to Remove the Last Character of a String?](https://www.baeldung.com/java-remove-last-character-of-string)
 - [Add a Character to a String at a Given Position](https://www.baeldung.com/java-add-character-to-string)
 - [Java Check a String for Lowercase/Uppercase Letter, Special Character and Digit](https://www.baeldung.com/java-lowercase-uppercase-special-character-digit-regex)
-- [Remove or Replace part of a String in Java](https://www.baeldung.com/java-remove-replace-string-part)
+- [Remove or Replace Part of a String in Java](https://www.baeldung.com/java-remove-replace-string-part)
 - [Replace a Character at a Specific Index in a String in Java](https://www.baeldung.com/java-replace-character-at-index)
 - [Join Array of Primitives with Separator in Java](https://www.baeldung.com/java-join-primitive-array)
 - [Pad a String with Zeros or Spaces in Java](https://www.baeldung.com/java-pad-string)

core-java-modules/core-java-string-algorithms-3/README.md

@@ -5,7 +5,7 @@ This module contains articles about string-related algorithms.
 ### Relevant Articles:
 
 - [Generating a Java String of N Repeated Characters](https://www.baeldung.com/java-string-of-repeated-characters)
-- [Check if Two Strings are Anagrams in Java](https://www.baeldung.com/java-strings-anagrams)
+- [Check if Two Strings Are Anagrams in Java](https://www.baeldung.com/java-strings-anagrams)
 - [Email Validation in Java](https://www.baeldung.com/java-email-validation-regex)
 - [Check if the First Letter of a String Is Uppercase](https://www.baeldung.com/java-check-first-letter-uppercase)
 - [Find the First Non Repeating Character in a String in Java](https://www.baeldung.com/java-find-the-first-non-repeating-character)

core-java-modules/core-java-string-algorithms/README.md

@@ -3,13 +3,13 @@
 This module contains articles about string-related algorithms.
 
 ### Relevant Articles:
-- [Check if a String is a Palindrome in Java](https://www.baeldung.com/java-palindrome)
+- [Check if a String Is a Palindrome in Java](https://www.baeldung.com/java-palindrome)
 - [Count Occurrences of a Char in a String](https://www.baeldung.com/java-count-chars)
 - [Using indexOf to Find All Occurrences of a Word in a String](https://www.baeldung.com/java-indexof-find-string-occurrences)
 - [Removing Stopwords from a String in Java](https://www.baeldung.com/java-string-remove-stopwords)
 - [Removing Repeated Characters from a String](https://www.baeldung.com/java-remove-repeated-char)
 - [How to Reverse a String in Java](https://www.baeldung.com/java-reverse-string)
-- [Check if a String is a Pangram in Java](https://www.baeldung.com/java-string-pangram)
+- [Check if a String Is a Pangram in Java](https://www.baeldung.com/java-string-pangram)
 - [Check If a String Contains Multiple Keywords in Java](https://www.baeldung.com/string-contains-multiple-words)
 - [Checking If a String Is a Repeated Substring](https://www.baeldung.com/java-repeated-substring)
 - [Remove Emojis from a Java String](https://www.baeldung.com/java-string-remove-emojis)

core-java-modules/core-java-string-operations-2/README.md

@@ -3,7 +3,7 @@
 This module contains articles about string operations.
 
 ### Relevant Articles:
-- [Concatenating Strings In Java](https://www.baeldung.com/java-strings-concatenation)
+- [Concatenating Strings in Java](https://www.baeldung.com/java-strings-concatenation)
 - [Checking for Empty or Blank Strings in Java](https://www.baeldung.com/java-blank-empty-strings)
 - [String Initialization in Java](https://www.baeldung.com/java-string-initialization)
 - [String toLowerCase and toUpperCase Methods in Java](https://www.baeldung.com/java-string-convert-case)

gradle-modules/gradle-customization/gradle-protobuf/settings.gradle

@@ -0,0 +1 @@
+rootProject.name = 'gradle-protobuf'

gradle-modules/gradle-customization/protobuf/settings.gradle

@@ -1 +0,0 @@
-rootProject.name = 'protobuf'

jackson-modules/jackson-conversions/README.md

@@ -5,7 +5,7 @@ This module contains articles about Jackson conversions.
 ### Relevant Articles:
 - [Jackson – Unmarshall to Collection/Array](https://www.baeldung.com/jackson-collection-array)
 - [Jackson Date](https://www.baeldung.com/jackson-serialize-dates)
-- [Jackson – Working with Maps and nulls](https://www.baeldung.com/jackson-map-null-values-or-null-key)
+- [Jackson – Working With Maps and Nulls](https://www.baeldung.com/jackson-map-null-values-or-null-key)
 - [Jackson – Decide What Fields Get Serialized/Deserialized](https://www.baeldung.com/jackson-field-serializable-deserializable-or-not)
 - [XML Serialization and Deserialization with Jackson](https://www.baeldung.com/jackson-xml-serialization-and-deserialization)
 - [Map Serialization and Deserialization with Jackson](https://www.baeldung.com/jackson-map)

jackson-modules/jackson-custom-conversions/README.md

@@ -5,6 +5,6 @@ This module contains articles about Jackson custom conversions.
 ### Relevant Articles:
 - [Jackson – Custom Serializer](https://www.baeldung.com/jackson-custom-serialization)
 - [Getting Started with Custom Deserialization in Jackson](https://www.baeldung.com/jackson-deserialization)
-- [Serialize Only Fields that meet a Custom Criteria with Jackson](https://www.baeldung.com/jackson-serialize-field-custom-criteria)
+- [Serialize Only Fields That Meet a Custom Criteria With Jackson](https://www.baeldung.com/jackson-serialize-field-custom-criteria)
 - [Calling Default Serializer from Custom Serializer in Jackson](https://www.baeldung.com/jackson-call-default-serializer-from-custom-serializer)
 - [OffsetDateTime Serialization With Jackson](https://www.baeldung.com/java-jackson-offsetdatetime)

javaxval/README.md

@@ -4,11 +4,11 @@ This module contains articles about Bean Validation.
 
 ### Relevant Articles: 
 - [Java Bean Validation Basics](https://www.baeldung.com/javax-validation)
-- [Validating Container Elements with Bean Validation 2.0](https://www.baeldung.com/bean-validation-container-elements)
+- [Validating Container Elements with Jakarta Bean Validation 3.0](https://www.baeldung.com/bean-validation-container-elements)
 - [Validations for Enum Types](https://www.baeldung.com/javax-validations-enums)
 - [Javax BigDecimal Validation](https://www.baeldung.com/javax-bigdecimal-validation)
 - [Grouping Javax Validation Constraints](https://www.baeldung.com/javax-validation-groups)
 - [Constraint Composition with Bean Validation](https://www.baeldung.com/java-bean-validation-constraint-composition)
 - [Using @NotNull on a Method Parameter](https://www.baeldung.com/java-notnull-method-parameter)
 - [Difference Between @NotNull, @NotEmpty, and @NotBlank Constraints in Bean Validation](https://www.baeldung.com/java-bean-validation-not-null-empty-blank)
-- More articles: [[next -->]](../javaxval-2)
+- More articles: [[next -->]](../javaxval-2)

json-modules/gson-2/README.md

@@ -3,5 +3,5 @@
 This module contains articles about Gson
 
 ### Relevant Articles: 
-
+- [Solving Gson Parsing Errors](https://www.baeldung.com/gson-parsing-errors)
 

jsoup/README.md

@@ -4,7 +4,7 @@ This module contains articles about jsoup.
 
 ### Relevant Articles: 
 - [Parsing HTML in Java with Jsoup](https://www.baeldung.com/java-with-jsoup)
-- [How to add proxy support to Jsoup?](https://www.baeldung.com/java-jsoup-proxy)
+- [How to Add Proxy Support to Jsoup?](https://www.baeldung.com/java-jsoup-proxy)
 - [Preserving Line Breaks When Using Jsoup](https://www.baeldung.com/jsoup-line-breaks)
 
 ### Build the Project

libraries-3/pom.xml

@@ -129,13 +129,6 @@
         </dependency>
     </dependencies>
 
-    <repositories>
-        <repository>
-            <id>jitpack.io</id>
-            <url>https://jitpack.io</url>
-        </repository>
-    </repositories>
-
     <build>
         <finalName>libraries-3</finalName>
         <plugins>

libraries-data-db/README.md

@@ -7,7 +7,7 @@ This module contains articles about database-related data processing libraries.
 - [Introduction to Reladomo](https://www.baeldung.com/reladomo)
 - [Introduction to ORMLite](https://www.baeldung.com/ormlite)
 - [Guide to Java Data Objects](https://www.baeldung.com/jdo)
-- [Intro to JDO Queries 2/2](https://www.baeldung.com/jdo-queries)
+- [Intro to JDO Queries](https://www.baeldung.com/jdo-queries)
 - [Introduction to HikariCP](https://www.baeldung.com/hikaricp)
 - [Guide to Ebean ORM](https://www.baeldung.com/ebean-orm)
 - [Introduction to Debezium](https://www.baeldung.com/debezium-intro)

libraries-http-2/pom.xml

@@ -82,7 +82,31 @@
             <artifactId>converter-gson</artifactId>
             <version>${retrofit.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-inline</artifactId>
+            <version>${mockito.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency> 
+    		<groupId>org.jmockit</groupId> 
+    		<artifactId>jmockit</artifactId> 
+    		<version>${jmockit.version}</version>
+		</dependency>
     </dependencies>
+    
+    <build>
+    	<plugins>
+    		<plugin>
+            	<artifactId>maven-surefire-plugin</artifactId>
+		            <configuration>
+		               <argLine>
+		                  -javaagent:${settings.localRepository}/org/jmockit/jmockit/${jmockit.version}/jmockit-${jmockit.version}.jar
+		               </argLine>
+		            </configuration>
+	         </plugin>
+    	</plugins>
+    </build>     
 
     <properties>
         <okhttp.version>4.9.1</okhttp.version>
@@ -95,6 +119,7 @@
         <spring.webflux.version>5.1.9.RELEASE</spring.webflux.version>
         <reactive.stream.version>1.0.3</reactive.stream.version>
         <reactor.version>3.2.12.RELEASE</reactor.version>
+        <jmockit.version>1.49</jmockit.version>
     </properties>
 
 </project>

libraries-http-2/src/main/java/com/baeldung/mock/url/UrlFetcher.java

@@ -0,0 +1,23 @@
+package com.baeldung.mock.url;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.URL;
+
+public class UrlFetcher {
+
+    private URL url;
+
+    public UrlFetcher(URL url) throws IOException {
+        this.url = url;
+    }
+
+    public boolean isUrlAvailable() throws IOException {
+        return getResponseCode() == HttpURLConnection.HTTP_OK;
+    }
+
+    private int getResponseCode() throws IOException {
+        HttpURLConnection con = (HttpURLConnection) this.url.openConnection();
+        return con.getResponseCode();
+    }
+}

libraries-http-2/src/test/java/com/baeldung/mock/url/MockHttpURLConnection.java

@@ -0,0 +1,35 @@
+package com.baeldung.mock.url;
+
+import java.io.IOException;
+import java.net.HttpURLConnection;
+import java.net.URL;
+
+public class MockHttpURLConnection extends HttpURLConnection {
+
+    protected MockHttpURLConnection(URL url) {
+        super(url);
+    }
+
+    @Override
+    public int getResponseCode() {
+        return responseCode;
+    }
+
+    public void setResponseCode(int responseCode) {
+        this.responseCode = responseCode;
+    }
+
+    @Override
+    public void disconnect() {
+    }
+
+    @Override
+    public boolean usingProxy() {
+        return false;
+    }
+
+    @Override
+    public void connect() throws IOException {
+    }
+
+}

libraries-http-2/src/test/java/com/baeldung/mock/url/MockURLStreamHandler.java

@@ -0,0 +1,21 @@
+package com.baeldung.mock.url;
+
+import java.io.IOException;
+import java.net.URL;
+import java.net.URLConnection;
+import java.net.URLStreamHandler;
+
+public class MockURLStreamHandler extends URLStreamHandler {
+
+    private MockHttpURLConnection mockHttpURLConnection;
+
+    public MockURLStreamHandler(MockHttpURLConnection mockHttpURLConnection) {
+        this.mockHttpURLConnection = mockHttpURLConnection;
+    }
+
+    @Override
+    protected URLConnection openConnection(URL url) throws IOException {
+        return this.mockHttpURLConnection;
+    }
+
+}

libraries-http-2/src/test/java/com/baeldung/mock/url/MockURLStreamHandlerFactory.java

@@ -0,0 +1,19 @@
+package com.baeldung.mock.url;
+
+import java.net.URLStreamHandler;
+import java.net.URLStreamHandlerFactory;
+
+public class MockURLStreamHandlerFactory implements URLStreamHandlerFactory {
+
+    private MockHttpURLConnection mockHttpURLConnection;
+
+    public MockURLStreamHandlerFactory(MockHttpURLConnection mockHttpURLConnection) {
+        this.mockHttpURLConnection = mockHttpURLConnection;
+    }
+
+    @Override
+    public URLStreamHandler createURLStreamHandler(String protocol) {
+        return new MockURLStreamHandler(this.mockHttpURLConnection);
+    }
+
+}

libraries-http-2/src/test/java/com/baeldung/mock/url/UrlFetcherJMockitUnitTest.java

@@ -0,0 +1,42 @@
+package com.baeldung.mock.url;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.net.HttpURLConnection;
+import java.net.URL;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+
+import mockit.Expectations;
+import mockit.Mocked;
+import mockit.integration.junit5.JMockitExtension;
+
+
+@ExtendWith(JMockitExtension.class)
+class UrlFetcherJMockitUnitTest {
+
+    @Test
+    void givenMockedUrl_whenRequestSent_thenIsUrlAvailableTrue(@Mocked URL anyURL, @Mocked HttpURLConnection mockConn) throws Exception {
+        new Expectations() {{
+                mockConn.getResponseCode();
+                result = HttpURLConnection.HTTP_OK;
+        }};
+
+        UrlFetcher fetcher = new UrlFetcher(new URL("https://www.baeldung.com/"));
+        assertTrue(fetcher.isUrlAvailable(), "Url should be available: ");
+    }
+    
+    @Test
+    void givenMockedUrl_whenRequestSent_thenIsUrlAvailableFalse(@Mocked URL anyURL, @Mocked HttpURLConnection mockConn) throws Exception {
+        new Expectations() {{
+                mockConn.getResponseCode();
+                result = HttpURLConnection.HTTP_INTERNAL_ERROR;
+        }};
+
+        UrlFetcher fetcher = new UrlFetcher(new URL("https://www.baeldung.com/"));
+        assertFalse(fetcher.isUrlAvailable(), "Url should NOT be available: ");
+    }
+
+}

libraries-http-2/src/test/java/com/baeldung/mock/url/UrlFetcherMockitoUnitTest.java

@@ -0,0 +1,39 @@
+package com.baeldung.mock.url;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+import java.net.HttpURLConnection;
+import java.net.URL;
+
+import org.junit.jupiter.api.Test;
+
+class UrlFetcherMockitoUnitTest {
+    
+    @Test
+    void givenMockedUrl_whenRequestSent_thenIsUrlAvailableTrue() throws Exception {
+        HttpURLConnection mockHttpURLConnection = mock(HttpURLConnection.class);
+        when(mockHttpURLConnection.getResponseCode()).thenReturn(HttpURLConnection.HTTP_OK);
+        
+        URL mockURL = mock(URL.class);
+        when(mockURL.openConnection()).thenReturn(mockHttpURLConnection);
+
+        UrlFetcher fetcher = new UrlFetcher(mockURL);
+        assertTrue(fetcher.isUrlAvailable(), "Url should be available: ");
+    }
+
+    @Test
+     void givenMockedUrl_whenRequestSent_thenIsUrlAvailableFalse() throws Exception {
+        HttpURLConnection mockHttpURLConnection = mock(HttpURLConnection.class);
+        when(mockHttpURLConnection.getResponseCode()).thenReturn(HttpURLConnection.HTTP_NOT_FOUND);
+        
+        URL mockURL = mock(URL.class);
+        when(mockURL.openConnection()).thenReturn(mockHttpURLConnection);
+        
+        UrlFetcher fetcher = new UrlFetcher(mockURL);
+        assertFalse(fetcher.isUrlAvailable(), "Url should NOT be available: ");
+    }
+
+}

libraries-http-2/src/test/java/com/baeldung/mock/url/UrlFetcherUnitTest.java

@@ -0,0 +1,40 @@
+package com.baeldung.mock.url;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.net.HttpURLConnection;
+import java.net.URL;
+
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+class UrlFetcherUnitTest {
+
+    private static MockHttpURLConnection mockHttpURLConnection;
+
+    @BeforeAll
+    public static void setUp() {
+        mockHttpURLConnection = new MockHttpURLConnection(null);
+        URL.setURLStreamHandlerFactory(new MockURLStreamHandlerFactory(mockHttpURLConnection));
+    }
+
+    @Test
+    void givenMockedUrl_whenRequestSent_thenIsUrlAvailableTrue() throws Exception {
+        mockHttpURLConnection.setResponseCode(HttpURLConnection.HTTP_OK);
+        URL url = new URL("https://www.baeldung.com/");
+
+        UrlFetcher fetcher = new UrlFetcher(url);
+        assertTrue(fetcher.isUrlAvailable(), "Url should be available: ");
+    }
+
+    @Test
+    void givenMockedUrl_whenRequestSent_thenIsUrlAvailableFalse() throws Exception {
+        mockHttpURLConnection.setResponseCode(HttpURLConnection.HTTP_FORBIDDEN);
+        URL url = new URL("https://www.baeldung.com/");
+
+        UrlFetcher fetcher = new UrlFetcher(url);
+        assertFalse(fetcher.isUrlAvailable(), "Url should NOT be available: ");
+    }
+
+}