Merge remote-tracking branch 'upstream/master'

algorithms-modules/algorithms-miscellaneous-5/src/main/java/com/baeldung/algorithms/maximumsubarray/KadaneAlgorithm.java

@@ -5,7 +5,7 @@ import org.slf4j.LoggerFactory;
 
 public class KadaneAlgorithm {
 
-    private Logger logger = LoggerFactory.getLogger(BruteForceAlgorithm.class.getName());
+    private Logger logger = LoggerFactory.getLogger(KadaneAlgorithm.class.getName());
 
     public int maxSubArraySum(int[] arr) {
 
@@ -14,15 +14,15 @@ public class KadaneAlgorithm {
         int end = 0;
 
         int maxSoFar = arr[0], maxEndingHere = arr[0];
+
         for (int i = 1; i < size; i++) {
-
+            maxEndingHere = maxEndingHere + arr[i];
-            if (arr[i] > maxEndingHere + arr[i]) {
+            if (arr[i] > maxEndingHere) {
-                start = i;
                 maxEndingHere = arr[i];
-            } else {
+                if (maxSoFar < maxEndingHere) {
-                maxEndingHere = maxEndingHere + arr[i];
+                    start = i;
+                }
             }
-
             if (maxSoFar < maxEndingHere) {
                 maxSoFar = maxEndingHere;
                 end = i;

algorithms-modules/algorithms-miscellaneous-5/src/test/java/com/baeldung/algorithms/maximumsubarray/KadaneAlgorithmUnitTest.java

@@ -7,7 +7,7 @@ import static org.junit.jupiter.api.Assertions.assertEquals;
 class KadaneAlgorithmUnitTest {
 
     @Test
-    void givenArrayWithNegativeNumberWhenMaximumSubarrayThenReturns6() {
+    void givenArrayWithNegativeNumberWhenMaximumSubarrayThenReturnsExpectedResult() {
         //given
         int[] arr = new int[] { -3, 1, -8, 4, -1, 2, 1, -5, 5 };
         //when
@@ -27,7 +27,7 @@ class KadaneAlgorithmUnitTest {
         //then
         assertEquals(-1, maxSum);
     }
-    
+
     @Test
     void givenArrayWithAllPosiitveNumbersWhenMaximumSubarrayThenReturnsExpectedResult() {
         //given
@@ -39,4 +39,15 @@ class KadaneAlgorithmUnitTest {
         assertEquals(10, maxSum);
     }
 
+    @Test
+    void givenArrayToTestStartIndexWhenMaximumSubarrayThenReturnsExpectedResult() {
+        //given
+        int[] arr = new int[] { 1, 2, -1, 3, -6, -2 };
+        //when
+        KadaneAlgorithm algorithm = new KadaneAlgorithm();
+        int maxSum = algorithm.maxSubArraySum(arr);
+        //then
+        assertEquals(5, maxSum);
+    }
+
 }

algorithms-modules/algorithms-miscellaneous-7/README.md

@@ -3,4 +3,5 @@
 - [Algorithm to Identify and Validate a Credit Card Number](https://www.baeldung.com/java-validate-cc-number)
 - [Find the N Most Frequent Elements in a Java Array](https://www.baeldung.com/java-n-most-frequent-elements-array)
 - [Getting Pixel Array From Image in Java](https://www.baeldung.com/java-getting-pixel-array-from-image)
+- [Calculate Distance Between Two Coordinates in Java](https://www.baeldung.com/java-find-distance-between-points)
 - More articles: [[<-- prev]](/algorithms-miscellaneous-6)

annotations/README.md

@@ -1,7 +0,0 @@
-## Annotations
-
-This module contains articles about Java annotations
-
-### Relevant Articles:
-
-- [Java Annotation Processing and Creating a Builder](https://www.baeldung.com/java-annotation-processing-builder)

annotations/pom.xml

@@ -1,21 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0"
-    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-    <modelVersion>4.0.0</modelVersion>
-    <artifactId>annotations</artifactId>
-    <name>annotations</name>
-    <packaging>pom</packaging>
-
-    <parent>
-        <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
-    </parent>
-
-    <modules>
-        <module>annotation-processing</module>
-        <module>annotation-user</module>
-    </modules>
-
-</project>

apache-cxf-modules/cxf-spring/pom.xml

@@ -43,19 +43,19 @@
         <dependency>
             <groupId>com.sun.xml.ws</groupId>
             <artifactId>jaxws-ri</artifactId>
-            <version>2.3.3</version>
+            <version>${jaxws-ri.version}</version>
             <type>pom</type>
         </dependency>
         <dependency>
             <groupId>javax.servlet</groupId>
             <artifactId>javax.servlet-api</artifactId>
-            <version>4.0.1</version>
+            <version>${javax.servlet-api.version}</version>
             <scope>provided</scope>
         </dependency>
         <dependency>
             <groupId>javax.servlet</groupId>
             <artifactId>jstl</artifactId>
-            <version>1.2</version>
+            <version>${jstl.version}</version>
         </dependency>
     </dependencies>
 
@@ -117,7 +117,9 @@
     <properties>
         <spring.version>5.3.25</spring.version>
         <cargo-maven2-plugin.version>1.6.1</cargo-maven2-plugin.version>
-        <maven-war-plugin.version>3.3.2</maven-war-plugin.version>
+        <jstl.version>1.2</jstl.version>
+        <javax.servlet-api.version>4.0.1</javax.servlet-api.version>
+        <jaxws-ri.version>2.3.3</jaxws-ri.version>
     </properties>
 
 </project>

apache-httpclient-2/src/test/java/com/baeldung/httpclient/cookies/HttpClientGettingCookieValueUnitTest.java

@@ -14,6 +14,7 @@ import org.apache.hc.client5.http.impl.classic.HttpClientBuilder;
 import org.apache.hc.client5.http.impl.cookie.BasicClientCookie;
 import org.apache.hc.client5.http.protocol.HttpClientContext;
 
+import org.apache.http.cookie.ClientCookie;
 import org.junit.jupiter.api.Test;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -51,8 +52,8 @@ class HttpClientGettingCookieValueUnitTest {
     private BasicCookieStore createCustomCookieStore() {
         BasicCookieStore cookieStore = new BasicCookieStore();
         BasicClientCookie cookie = new BasicClientCookie("custom_cookie", "test_value");
-        cookie.setDomain("baeldung.com");
+        cookie.setDomain("github.com");
-        cookie.setAttribute("domain", "true");
+        cookie.setAttribute(ClientCookie.DOMAIN_ATTR, "github.com");
         cookie.setPath("/");
         cookieStore.addCookie(cookie);
         return cookieStore;

apache-httpclient-2/src/test/java/com/baeldung/httpclient/readresponsebodystring/ApacheHttpClient5UnitTest.java

@@ -16,7 +16,7 @@ public class ApacheHttpClient5UnitTest {
     public static final String DUMMY_URL = "https://postman-echo.com/get";
 
     @Test
-    public void whenUseApacheHttpClient_thenCorrect() throws IOException {
+    void whenUseApacheHttpClient_thenCorrect() throws IOException {
         HttpGet request = new HttpGet(DUMMY_URL);
 
         try (CloseableHttpClient client = HttpClients.createDefault()) {

apache-httpclient-2/src/test/java/com/baeldung/httpclient/readresponsebodystring/HttpClientUnitTest.java

@@ -1,6 +1,5 @@
 package com.baeldung.httpclient.readresponsebodystring;
 
-import org.junit.Test;
 
 import java.io.IOException;
 import java.net.URI;
@@ -8,11 +7,13 @@ import java.net.http.HttpClient;
 import java.net.http.HttpRequest;
 import java.net.http.HttpResponse;
 
-public class HttpClientUnitTest {
+import org.junit.jupiter.api.Test;
+
+class HttpClientUnitTest {
     public static final String DUMMY_URL = "https://postman-echo.com/get";
 
     @Test
-    public void whenUseHttpClient_thenCorrect() throws IOException, InterruptedException {
+    void whenUseHttpClient_thenCorrect() throws IOException, InterruptedException {
         HttpClient client = HttpClient.newHttpClient();
         HttpRequest request = HttpRequest.newBuilder().uri(URI.create(DUMMY_URL)).build();
 

apache-httpclient-2/src/test/java/com/baeldung/httpclient/readresponsebodystring/HttpUrlConnectionUnitTest.java

@@ -1,7 +1,7 @@
 package com.baeldung.httpclient.readresponsebodystring;
 
-import org.junit.Assert;
+
-import org.junit.Test;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 
 import java.io.BufferedReader;
 import java.io.IOException;
@@ -10,12 +10,14 @@ import java.io.InputStreamReader;
 import java.net.HttpURLConnection;
 import java.net.URL;
 
+import org.junit.jupiter.api.Test;
+
 public class HttpUrlConnectionUnitTest {
 
     public static final String DUMMY_URL = "https://postman-echo.com/get";
 
     @Test
-    public void whenUseHttpUrlConnection_thenCorrect() throws IOException {
+    void whenUseHttpUrlConnection_thenCorrect() throws IOException {
         HttpURLConnection connection = (HttpURLConnection) new URL(DUMMY_URL).openConnection();
 
         InputStream inputStream = connection.getInputStream();
@@ -28,7 +30,7 @@ public class HttpUrlConnectionUnitTest {
             response.append(currentLine);
 
         in.close();
-        Assert.assertNotNull(response.toString());
+        assertNotNull(response.toString());
         System.out.println("Response -> " + response.toString());
     }
 }

apache-httpclient-2/src/test/java/com/baeldung/httpclient/readresponsebodystring/SpringRestTemplateUnitTest.java

@@ -1,6 +1,6 @@
 package com.baeldung.httpclient.readresponsebodystring;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 import org.springframework.web.client.RestTemplate;
 
 public class SpringRestTemplateUnitTest {

apache-httpclient-2/src/test/java/com/baeldung/httpclient/readresponsebodystring/SpringWebClientUnitTest.java

@@ -1,6 +1,6 @@
 package com.baeldung.httpclient.readresponsebodystring;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 import org.springframework.web.reactive.function.client.WebClient;
 import reactor.core.publisher.Mono;
 
@@ -8,7 +8,7 @@ public class SpringWebClientUnitTest {
     public static final String DUMMY_URL = "https://postman-echo.com/get";
 
     @Test
-    public void whenUseWebClientRetrieve_thenCorrect() {
+    void whenUseWebClientRetrieve_thenCorrect() {
         WebClient webClient = WebClient.create(DUMMY_URL);
         Mono<String> body = webClient.get().retrieve().bodyToMono(String.class);
         String s = body.block();

apache-httpclient-2/src/test/resources/logback.xml

@@ -4,6 +4,7 @@
             <pattern>%date [%level] %logger - %msg %n</pattern>
         </encoder>
     </appender>
+    <logger name="com.baeldung.httpclient.cookies" level="info"/>
 
     <logger name="com.baeldung.httpclient.readresponsebodystring" level="debug"/>
     <logger name="org.apache.http" level="debug"/>

apache-httpclient/pom.xml

@@ -15,45 +15,6 @@
     </parent>
 
     <dependencies>
-        <!-- http client -->
-        <dependency>
-            <groupId>org.apache.httpcomponents</groupId>
-            <artifactId>httpclient</artifactId>
-            <version>${httpclient.version}</version>
-            <exclusions>
-                <exclusion>
-                    <artifactId>commons-logging</artifactId>
-                    <groupId>commons-logging</groupId>
-                </exclusion>
-            </exclusions>
-        </dependency>
-        <dependency>
-            <groupId>org.apache.httpcomponents</groupId>
-            <artifactId>fluent-hc</artifactId>
-            <version>${httpclient.version}</version>
-            <exclusions>
-                <exclusion>
-                    <artifactId>commons-logging</artifactId>
-                    <groupId>commons-logging</groupId>
-                </exclusion>
-            </exclusions>
-        </dependency>
-        <dependency>
-            <groupId>org.apache.httpcomponents</groupId>
-            <artifactId>httpmime</artifactId>
-            <version>${httpclient.version}</version>
-        </dependency>
-        <dependency>
-            <groupId>org.apache.httpcomponents</groupId>
-            <artifactId>httpasyncclient</artifactId>
-            <version>${httpasyncclient.version}</version> <!-- 4.0.2 --> <!-- 4.1-beta1 -->
-            <exclusions>
-                <exclusion>
-                    <artifactId>commons-logging</artifactId>
-                    <groupId>commons-logging</groupId>
-                </exclusion>
-            </exclusions>
-        </dependency>
         <dependency>
             <groupId>org.apache.httpcomponents.core5</groupId>
             <artifactId>httpcore5</artifactId>
@@ -115,12 +76,8 @@
     </build>
 
     <properties>
-        <!-- 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 -->
         <httpcore5.version>5.2</httpcore5.version>
         <httpclient5.version>5.2</httpclient5.version>

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

@@ -4,10 +4,10 @@ import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.equalTo;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
-import org.apache.hc.core5.http.ParseException;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
+
 import org.apache.hc.client5.http.classic.methods.HttpPost;
 import org.apache.hc.client5.http.entity.mime.FileBody;
 import org.apache.hc.client5.http.entity.mime.HttpMultipartMode;
@@ -19,6 +19,7 @@ import org.apache.hc.client5.http.impl.classic.HttpClientBuilder;
 import org.apache.hc.core5.http.ContentType;
 import org.apache.hc.core5.http.HttpEntity;
 import org.apache.hc.core5.http.HttpStatus;
+import org.apache.hc.core5.http.ParseException;
 
 import java.io.BufferedReader;
 import java.io.File;
@@ -30,9 +31,6 @@ import java.net.URL;
 
 class HttpClientMultipartLiveTest extends GetRequestMockServer {
 
-    // No longer available
-    // private static final String SERVER = "http://echo.200please.com";
-
     private static final String SERVER = "http://localhost:8080/spring-mvc-java/stub/multipart";
     private static final String TEXTFILENAME = "temp.txt";
     private static final String IMAGEFILENAME = "image.jpg";

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

@@ -1,15 +1,16 @@
 package com.baeldung.httpclient;
 
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.equalTo;
+
+import org.junit.jupiter.api.Test;
+
 import org.apache.hc.client5.http.classic.methods.HttpGet;
 import org.apache.hc.client5.http.classic.methods.HttpPost;
 import org.apache.hc.client5.http.impl.DefaultRedirectStrategy;
 import org.apache.hc.client5.http.impl.classic.CloseableHttpClient;
 import org.apache.hc.client5.http.impl.classic.HttpClientBuilder;
 import org.apache.hc.client5.http.impl.classic.HttpClients;
-import org.junit.jupiter.api.Test;
-
-import static org.hamcrest.MatcherAssert.assertThat;
-import static org.hamcrest.Matchers.equalTo;
 
 import java.io.IOException;
 

apache-httpclient/src/test/java/com/baeldung/httpclient/advancedconfig/HttpClientAdvancedConfigurationIntegrationTest.java

@@ -8,7 +8,7 @@ import static com.github.tomakehurst.wiremock.client.WireMock.getRequestedFor;
 import static com.github.tomakehurst.wiremock.client.WireMock.post;
 import static com.github.tomakehurst.wiremock.client.WireMock.urlEqualTo;
 import static com.github.tomakehurst.wiremock.client.WireMock.urlMatching;
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 import java.io.IOException;
 
@@ -29,21 +29,34 @@ import org.apache.hc.core5.http.HttpHeaders;
 import org.apache.hc.core5.http.HttpHost;
 import org.apache.hc.core5.http.HttpResponse;
 import org.apache.hc.core5.http.io.entity.StringEntity;
-import org.junit.Rule;
-import org.junit.Test;
 
-import com.github.tomakehurst.wiremock.junit.WireMockRule;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
-public class HttpClientAdvancedConfigurationIntegrationTest {
+import com.github.tomakehurst.wiremock.WireMockServer;
 
-    @Rule
+class HttpClientAdvancedConfigurationIntegrationTest {
-    public WireMockRule serviceMock = new WireMockRule(8089);
 
-    @Rule
+    public WireMockServer serviceMock;
-    public WireMockRule proxyMock = new WireMockRule(8090);
+    public WireMockServer proxyMock;
+
+    @BeforeEach
+    public void before () {
+        serviceMock = new WireMockServer(8089);
+        serviceMock.start();
+        proxyMock = new WireMockServer(8090);
+        proxyMock.start();
+    }
+
+    @AfterEach
+    public void after () {
+        serviceMock.stop();
+        proxyMock.stop();
+    }
 
     @Test
-    public void givenClientWithCustomUserAgentHeader_whenExecuteRequest_shouldReturn200() throws IOException {
+    void givenClientWithCustomUserAgentHeader_whenExecuteRequest_shouldReturn200() throws IOException {
         //given
         String userAgent = "BaeldungAgent/1.0";
         serviceMock.stubFor(get(urlEqualTo("/detail"))
@@ -59,11 +72,11 @@ public class HttpClientAdvancedConfigurationIntegrationTest {
         HttpResponse response = httpClient.execute(httpGet);
 
         //then
-        assertEquals(response.getCode(), 200);
+        assertEquals(200, response.getCode());
     }
 
     @Test
-    public void givenClientThatSendDataInBody_whenSendXmlInBody_shouldReturn200() throws IOException {
+    void givenClientThatSendDataInBody_whenSendXmlInBody_shouldReturn200() throws IOException {
         //given
         String xmlBody = "<xml><id>1</id></xml>";
         serviceMock.stubFor(post(urlEqualTo("/person"))
@@ -82,12 +95,12 @@ public class HttpClientAdvancedConfigurationIntegrationTest {
         HttpResponse response = httpClient.execute(httpPost);
 
         //then
-        assertEquals(response.getCode(), 200);
+        assertEquals(200, response.getCode());
 
     }
 
     @Test
-    public void givenServerThatIsBehindProxy_whenClientIsConfiguredToSendRequestViaProxy_shouldReturn200() throws IOException {
+    void givenServerThatIsBehindProxy_whenClientIsConfiguredToSendRequestViaProxy_shouldReturn200() throws IOException {
         //given
         proxyMock.stubFor(get(urlMatching(".*"))
           .willReturn(aResponse().proxiedFrom("http://localhost:8089/")));
@@ -107,7 +120,7 @@ public class HttpClientAdvancedConfigurationIntegrationTest {
         HttpResponse response = httpclient.execute(httpGet);
 
         //then
-        assertEquals(response.getCode(), 200);
+        assertEquals(200, response.getCode());
         proxyMock.verify(getRequestedFor(urlEqualTo("/private")));
         serviceMock.verify(getRequestedFor(urlEqualTo("/private")));
     }
@@ -151,7 +164,7 @@ public class HttpClientAdvancedConfigurationIntegrationTest {
         HttpResponse response = httpclient.execute(httpGet, context);
 
         //then
-        assertEquals(response.getCode(), 200);
+        assertEquals(200, response.getCode());
         proxyMock.verify(getRequestedFor(urlEqualTo("/private")).withHeader("Authorization", containing("Basic")));
         serviceMock.verify(getRequestedFor(urlEqualTo("/private")));
     }

apache-httpclient/src/test/java/com/baeldung/httpclient/base/HttpClientBasicPostLiveTest.java

@@ -1,59 +0,0 @@
-package com.baeldung.httpclient.base;
-
-import com.baeldung.httpclient.ResponseUtil;
-import org.apache.http.auth.AuthenticationException;
-import org.apache.http.auth.UsernamePasswordCredentials;
-import org.apache.http.client.methods.CloseableHttpResponse;
-import org.apache.http.client.methods.HttpPost;
-import org.apache.http.entity.StringEntity;
-import org.apache.http.impl.auth.BasicScheme;
-import org.apache.http.impl.client.CloseableHttpClient;
-import org.apache.http.impl.client.HttpClientBuilder;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-
-import java.io.IOException;
-
-public class HttpClientBasicPostLiveTest {
-
-    private static final String SAMPLE_URL = "http://www.github.com";
-
-    private CloseableHttpClient instance;
-
-    private CloseableHttpResponse response;
-
-    @Before
-    public final void before() {
-        instance = HttpClientBuilder.create().build();
-    }
-
-    @After
-    public final void after() throws IllegalStateException, IOException {
-        ResponseUtil.closeResponse(response);
-    }
-
-    // tests - non-GET
-
-    @Test
-    public final void whenExecutingPostRequest_thenNoExceptions() throws IOException {
-        instance.execute(new HttpPost(SAMPLE_URL));
-    }
-
-    @Test
-    public final void whenExecutingPostRequestWithBody_thenNoExceptions() throws IOException {
-        final HttpPost request = new HttpPost(SAMPLE_URL);
-        request.setEntity(new StringEntity("in the body of the POST"));
-        instance.execute(request);
-    }
-
-    @Test
-    public final void givenAuth_whenExecutingPostRequestWithBody_thenNoExceptions() throws IOException, AuthenticationException {
-        final HttpPost request = new HttpPost(SAMPLE_URL);
-        request.setEntity(new StringEntity("in the body of the POST"));
-        final UsernamePasswordCredentials creds = new UsernamePasswordCredentials("username", "password");
-        request.addHeader(new BasicScheme().authenticate(creds, request, null));
-        instance.execute(request);
-    }
-
-}

apache-httpclient/src/test/java/com/baeldung/httpclient/base/HttpClientLiveTest.java

@@ -1,75 +0,0 @@
-package com.baeldung.httpclient.base;
-
-import com.baeldung.httpclient.ResponseUtil;
-
-import org.apache.http.Header;
-import org.apache.http.HttpHeaders;
-import org.apache.http.client.config.RequestConfig;
-import org.apache.http.client.methods.CloseableHttpResponse;
-import org.apache.http.client.methods.HttpGet;
-import org.apache.http.conn.ConnectTimeoutException;
-import org.apache.http.impl.client.CloseableHttpClient;
-import org.apache.http.impl.client.HttpClientBuilder;
-import org.apache.http.impl.conn.BasicHttpClientConnectionManager;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-
-import java.io.IOException;
-
-import static org.hamcrest.Matchers.emptyArray;
-import static org.hamcrest.Matchers.not;
-import static org.junit.Assert.assertThat;
-
-public class HttpClientLiveTest {
-
-    private static final String SAMPLE_URL = "http://www.github.com";
-
-    private CloseableHttpClient instance;
-
-    private CloseableHttpResponse response;
-
-    @Before
-    public final void before() {
-        instance = HttpClientBuilder.create().build();
-    }
-
-    @After
-    public final void after() throws IllegalStateException, IOException {
-        ResponseUtil.closeResponse(response);
-    }
-
-    // tests
-
-    @Test(expected = ConnectTimeoutException.class)
-    public final void givenLowTimeout_whenExecutingRequestWithTimeout_thenException() throws IOException {
-        final RequestConfig requestConfig = RequestConfig.custom().setConnectionRequestTimeout(5).setConnectTimeout(5).setSocketTimeout(2).build();
-        final HttpGet request = new HttpGet(SAMPLE_URL);
-        request.setConfig(requestConfig);
-        response = instance.execute(request);
-    }
-
-    // tests - configs
-
-    @Test
-    public final void givenHttpClientIsConfiguredWithCustomConnectionManager_whenExecutingRequest_thenNoExceptions() throws IOException {
-        instance = HttpClientBuilder.create().setConnectionManager(new BasicHttpClientConnectionManager()).build();
-        response = instance.execute(new HttpGet(SAMPLE_URL));
-    }
-
-    @Test
-    public final void givenCustomHeaderIsSet_whenSendingRequest_thenNoExceptions() throws IOException {
-        final HttpGet request = new HttpGet(SAMPLE_URL);
-        request.addHeader(HttpHeaders.ACCEPT, "application/xml");
-        response = instance.execute(request);
-    }
-
-    @Test
-    public final void givenRequestWasSet_whenAnalyzingTheHeadersOfTheResponse_thenCorrect() throws IOException {
-        response = instance.execute(new HttpGet(SAMPLE_URL));
-
-        final Header[] headers = response.getHeaders(HttpHeaders.CONTENT_TYPE);
-        assertThat(headers, not(emptyArray()));
-    }
-
-}

apache-httpclient/src/test/java/com/baeldung/httpclient/conn/HttpClientConnectionManagementLiveTest.java

@@ -1,5 +1,6 @@
 package com.baeldung.httpclient.conn;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
@@ -34,14 +35,13 @@ import org.apache.hc.core5.pool.PoolStats;
 import org.apache.hc.core5.util.Args;
 import org.apache.hc.core5.util.TimeValue;
 import org.apache.hc.core5.util.Timeout;
-import org.junit.Assert;
+import org.junit.jupiter.api.Test;
-import org.junit.Test;
 
-public class HttpClientConnectionManagementLiveTest {
+class HttpClientConnectionManagementLiveTest {
 
     // Example 2.1. Getting a Connection Request for a Low Level Connection (HttpClientConnection)
     @Test
-    public final void whenLowLevelConnectionIsEstablished_thenNoExceptions() throws ExecutionException, InterruptedException, TimeoutException {
+    final void whenLowLevelConnectionIsEstablished_thenNoExceptions() throws ExecutionException, InterruptedException, TimeoutException {
         BasicHttpClientConnectionManager connMgr = new BasicHttpClientConnectionManager();
         HttpRoute route = new HttpRoute(new HttpHost("www.baeldung.com", 443));
         final LeaseRequest connRequest = connMgr.lease("some-id", route, null);
@@ -51,7 +51,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 3.1. Setting the PoolingHttpClientConnectionManager on a HttpClient
     @Test
-    public final void whenPollingConnectionManagerIsConfiguredOnHttpClient_thenNoExceptions() throws IOException {
+    final void whenPollingConnectionManagerIsConfiguredOnHttpClient_thenNoExceptions() throws IOException {
         PoolingHttpClientConnectionManager poolingConnManager = new PoolingHttpClientConnectionManager();
         CloseableHttpClient client = HttpClients.custom()
             .setConnectionManager(poolingConnManager)
@@ -65,7 +65,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 3.2. Using Two HttpClients to Connect to One Target Host Each
     @Test
-    public final void whenTwoConnectionsForTwoRequests_thenNoExceptions() throws InterruptedException, IOException {
+    final void whenTwoConnectionsForTwoRequests_thenNoExceptions() throws InterruptedException, IOException {
         HttpGet get1 = new HttpGet("https://www.baeldung.com");
         HttpGet get2 = new HttpGet("https://www.google.com");
         PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
@@ -83,8 +83,7 @@ public class HttpClientConnectionManagementLiveTest {
         thread1.join();
         thread2.join();
 
-        Assert.assertTrue(connManager.getTotalStats()
+        assertEquals(0, connManager.getTotalStats().getLeased());
-            .getLeased() == 0);
         client1.close();
         client2.close();
         connManager.close();
@@ -92,7 +91,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 4.1. Increasing the Number of Connections that Can be Open and Managed Beyond the default Limits
     @Test
-    public final void whenIncreasingConnectionPool_thenNoExceptions() {
+    final void whenIncreasingConnectionPool_thenNoExceptions() {
         PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
         connManager.setMaxTotal(5);
         connManager.setDefaultMaxPerRoute(4);
@@ -103,7 +102,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 4.2. Using Threads to Execute Connections
     @Test
-    public final void whenExecutingSameRequestsInDifferentThreads_thenExecuteRequest() throws InterruptedException, IOException {
+    final void whenExecutingSameRequestsInDifferentThreads_thenExecuteRequest() throws InterruptedException, IOException {
         HttpGet get = new HttpGet("http://www.baeldung.com");
         PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
         CloseableHttpClient client = HttpClients.custom()
@@ -133,7 +132,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 5.1. A Custom Keep Alive Strategy
     @Test
-    public final void whenCustomizingKeepAliveStrategy_thenNoExceptions() {
+    final void whenCustomizingKeepAliveStrategy_thenNoExceptions() {
         final ConnectionKeepAliveStrategy myStrategy = new ConnectionKeepAliveStrategy() {
             @Override
             public TimeValue getKeepAliveDuration(HttpResponse response, HttpContext context) {
@@ -162,7 +161,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     //Example 6.1. BasicHttpClientConnectionManager Connection Reuse
     @Test
-    public final void givenBasicHttpClientConnManager_whenConnectionReuse_thenNoExceptions() throws InterruptedException, ExecutionException, TimeoutException, IOException, URISyntaxException {
+    final void givenBasicHttpClientConnManager_whenConnectionReuse_thenNoExceptions() throws InterruptedException, ExecutionException, TimeoutException, IOException, URISyntaxException {
         BasicHttpClientConnectionManager connMgr = new BasicHttpClientConnectionManager();
         HttpRoute route = new HttpRoute(new HttpHost("www.baeldung.com", 443));
         final HttpContext context = new BasicHttpContext();
@@ -184,7 +183,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 6.2. PoolingHttpClientConnectionManager: Re-Using Connections with Threads
     @Test
-    public final void whenConnectionsNeededGreaterThanMaxTotal_thenLeaseMasTotalandReuse() throws InterruptedException, IOException {
+    final void whenConnectionsNeededGreaterThanMaxTotal_thenLeaseMasTotalandReuse() throws InterruptedException, IOException {
         HttpGet get = new HttpGet("http://www.baeldung.com");
         PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
         connManager.setDefaultMaxPerRoute(6);
@@ -208,7 +207,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 7.1. Setting Socket Timeout to 5 Seconds
     @Test
-    public final void whenConfiguringTimeOut_thenNoExceptions() throws ExecutionException, InterruptedException, TimeoutException, IOException {
+    final void whenConfiguringTimeOut_thenNoExceptions() throws ExecutionException, InterruptedException, TimeoutException, IOException {
         final HttpRoute route = new HttpRoute(new HttpHost("www.baeldung.com", 80));
         final HttpContext context = new BasicHttpContext();
         final PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
@@ -227,7 +226,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 8.1. Setting the HttpClient to Check for Stale Connections
     @Test
-    public final void whenEvictIdealConn_thenNoExceptions() throws InterruptedException, IOException {
+    final void whenEvictIdealConn_thenNoExceptions() throws InterruptedException, IOException {
         final PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
         connManager.setMaxTotal(100);
         try (final CloseableHttpClient httpclient = HttpClients.custom()
@@ -266,7 +265,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 9.1. Closing Connection and Releasing Resources
     @Test
-    public final void whenClosingConnectionsandManager_thenCloseWithNoExceptions1() throws IOException {
+    final void whenClosingConnectionsAndManager_thenCloseWithNoExceptions1() throws IOException {
         PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
         CloseableHttpClient client = HttpClients.custom()
             .setConnectionManager(connManager)
@@ -282,7 +281,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     @Test
     // Example 3.2. TESTER VERSION
-    public final void whenTwoConnectionsForTwoRequests_thenTwoConnectionsAreLeased() throws InterruptedException, IOException {
+    final void whenTwoConnectionsForTwoRequests_thenTwoConnectionsAreLeased() throws InterruptedException, IOException {
         HttpGet get1 = new HttpGet("https://www.baeldung.com");
         HttpGet get2 = new HttpGet("https://www.google.com");
 
@@ -300,8 +299,7 @@ public class HttpClientConnectionManagementLiveTest {
         thread2.start();
         thread1.join();
         thread2.join(1000);
-        Assert.assertTrue(poolingConnManager.getTotalStats()
+        assertEquals(2, poolingConnManager.getTotalStats().getLeased());
-            .getLeased() == 2);
 
         client1.close();
         client2.close();

apache-httpclient/src/test/java/com/baeldung/httpclient/conn/IdleConnectionMonitorThread.java

@@ -1,41 +0,0 @@
-package com.baeldung.httpclient.conn;
-
-import java.util.concurrent.TimeUnit;
-
-import org.apache.http.conn.HttpClientConnectionManager;
-import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
-
-public class IdleConnectionMonitorThread extends Thread {
-    private final HttpClientConnectionManager connMgr;
-    private volatile boolean shutdown;
-
-    IdleConnectionMonitorThread(final PoolingHttpClientConnectionManager connMgr) {
-        super();
-        this.connMgr = connMgr;
-    }
-
-    // API
-
-    @Override
-    public final void run() {
-        try {
-            while (!shutdown) {
-                synchronized (this) {
-                    wait(1000);
-                    connMgr.closeExpiredConnections();
-                    connMgr.closeIdleConnections(30, TimeUnit.SECONDS);
-                }
-            }
-        } catch (final InterruptedException ex) {
-            shutdown();
-        }
-    }
-
-    private void shutdown() {
-        shutdown = true;
-        synchronized (this) {
-            notifyAll();
-        }
-    }
-
-}

apache-httpclient/src/test/java/com/baeldung/httpclient/conn/MultiHttpClientConnThread.java

@@ -6,7 +6,6 @@ import org.apache.hc.client5.http.classic.methods.HttpGet;
 import org.apache.hc.client5.http.impl.classic.CloseableHttpClient;
 import org.apache.hc.client5.http.impl.io.PoolingHttpClientConnectionManager;
 import org.apache.hc.core5.http.HttpEntity;
-import org.apache.hc.core5.http.HttpResponse;
 import org.apache.hc.core5.http.io.entity.EntityUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

apache-httpclient4/pom.xml

@@ -241,8 +241,6 @@
         <httpcore.version>4.4.16</httpcore.version>
         <httpclient.version>4.5.14</httpclient.version>
         <mockserver.version>5.11.2</mockserver.version>
-        <!-- maven plugins -->
-        <maven-war-plugin.version>3.3.2</maven-war-plugin.version>
     </properties>
 
 </project>

apache-httpclient4/src/test/java/com/baeldung/client/HttpClientSandboxLiveTest.java

@@ -1,7 +1,7 @@
-package com.baeldung.httpclient.base;
+package com.baeldung.client;
+
+import java.io.IOException;
 
-import com.baeldung.httpclient.GetRequestMockServer;
-import com.baeldung.httpclient.ResponseUtil;
 import org.apache.http.auth.AuthScope;
 import org.apache.http.auth.UsernamePasswordCredentials;
 import org.apache.http.client.CredentialsProvider;
@@ -12,15 +12,16 @@ import org.apache.http.impl.client.CloseableHttpClient;
 import org.apache.http.impl.client.HttpClientBuilder;
 import org.junit.jupiter.api.Test;
 
-import java.io.IOException;
+import com.baeldung.GetRequestMockServer;
+import com.baeldung.httpclient.ResponseUtil;
 
 /*
  * NOTE : Need module spring-security-rest-basic-auth to be running
  */
-public class HttpClientSandboxLiveTest extends GetRequestMockServer {
+class HttpClientSandboxLiveTest extends GetRequestMockServer {
 
     @Test
-    public final void givenGetRequestExecuted_whenAnalyzingTheResponse_thenCorrectStatusCode() throws IOException {
+    final void givenGetRequestExecuted_whenAnalyzingTheResponse_thenCorrectStatusCode() throws IOException {
         final CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
         final AuthScope authscp = new AuthScope("localhost", 8080);
         credentialsProvider.setCredentials(authscp, new UsernamePasswordCredentials("user1", "user1Pass"));

apache-httpclient4/src/test/java/com/baeldung/client/RestClientV4LiveManualTest.java

@@ -35,7 +35,7 @@ import org.springframework.web.client.RestTemplate;
  * This test requires a localhost server over HTTPS <br>
  * It should only be manually run, not part of the automated build
  * */
-public class RestClientV4LiveManualTest {
+class RestClientV4LiveManualTest {
 
     final String urlOverHttps = "http://localhost:8082/httpclient-simple/api/bars/1";
 
@@ -81,7 +81,7 @@ public class RestClientV4LiveManualTest {
     }
 
     @Test
-    public void whenHttpsUrlIsConsumed_thenException() throws ClientProtocolException, IOException {
+    void whenHttpsUrlIsConsumed_thenException() throws ClientProtocolException, IOException {
         CloseableHttpClient httpClient = HttpClients.createDefault();
         String urlOverHttps = "https://localhost:8082/httpclient-simple";
         HttpGet getMethod = new HttpGet(urlOverHttps);

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

@@ -2,8 +2,6 @@ package com.baeldung.httpclient;
 
 import java.io.IOException;
 
-import org.apache.http.HttpEntity;
-import org.apache.http.client.methods.CloseableHttpResponse;
 import org.apache.http.impl.client.CloseableHttpClient;
 
 public final class ClientUtil {

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

@@ -1,4 +1,5 @@
 package com.baeldung.httpclient;
+
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.equalTo;
 

apache-httpclient4/src/test/java/com/baeldung/httpclient/HttpClientCancelRequestV4LiveTest.java

@@ -9,11 +9,11 @@ import org.apache.http.impl.client.CloseableHttpClient;
 import org.apache.http.impl.client.HttpClientBuilder;
 import org.apache.http.impl.client.HttpClients;
 
-import org.junit.After;
+import org.junit.jupiter.api.AfterEach;
-import org.junit.Before;
+import org.junit.jupiter.api.BeforeEach;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
-public class HttpClientCancelRequestV4LiveTest {
+class HttpClientCancelRequestV4LiveTest {
 
     private static final String SAMPLE_URL = "http://www.github.com";
 
@@ -21,18 +21,18 @@ public class HttpClientCancelRequestV4LiveTest {
 
     private CloseableHttpResponse response;
 
-    @Before
+    @BeforeEach
     public final void before() {
         instance = HttpClientBuilder.create().build();
     }
 
-    @After
+    @AfterEach
     public final void after() throws IllegalStateException, IOException {
         ResponseUtil.closeResponse(response);
     }
 
     @Test
-    public final void whenRequestIsCanceled_thenCorrect() throws IOException {
+    final void whenRequestIsCanceled_thenCorrect() throws IOException {
         instance = HttpClients.custom().build();
         final HttpGet request = new HttpGet(SAMPLE_URL);
         response = instance.execute(request);

apache-httpclient4/src/test/java/com/baeldung/httpclient/HttpClientCookBookV4LiveTest.java

@@ -1,5 +1,9 @@
 package com.baeldung.httpclient;
 
+import org.apache.http.auth.AuthenticationException;
+import org.apache.http.auth.UsernamePasswordCredentials;
+import org.apache.http.entity.StringEntity;
+import org.apache.http.impl.auth.BasicScheme;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
@@ -181,4 +185,20 @@ class HttpClientCookBookV4LiveTest {
         }
     }
 
+    @Test
+    final void whenExecutingPostRequestWithBody_thenNoExceptions() throws IOException {
+        final HttpPost request = new HttpPost(SAMPLE_POST_URL);
+        request.setEntity(new StringEntity("in the body of the POST"));
+        client.execute(request);
+    }
+
+    @Test
+    final void givenAuth_whenExecutingPostRequestWithBody_thenNoExceptions() throws IOException, AuthenticationException {
+        final HttpPost request = new HttpPost(SAMPLE_POST_URL);
+        request.setEntity(new StringEntity("in the body of the POST"));
+        final UsernamePasswordCredentials creds = new UsernamePasswordCredentials("username", "password");
+        request.addHeader(new BasicScheme().authenticate(creds, request, null));
+        client.execute(request);
+    }
+
 }

apache-httpclient4/src/test/java/com/baeldung/httpclient/HttpClientRedirectV4LiveTest.java

@@ -1,12 +1,12 @@
 package com.baeldung.httpclient;
 
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.equalTo;
+
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import static org.hamcrest.MatcherAssert.assertThat;
-import static org.hamcrest.Matchers.equalTo;
-
 import java.io.IOException;
 
 import org.apache.http.client.methods.CloseableHttpResponse;

apache-httpclient4/src/test/java/com/baeldung/httpclient/HttpClientTimeoutV4LiveTest.java

@@ -92,6 +92,26 @@ class HttpClientTimeoutV4LiveTest extends GetRequestMockServer {
 
     }
 
+    @Test
+    final void givenLowTimeout_whenExecutingRequestWithTimeout_thenException() {
+        final RequestConfig requestConfig = RequestConfig.custom()
+            .setConnectionRequestTimeout(5)
+            .setConnectTimeout(5)
+            .setSocketTimeout(2)
+            .build();
+
+        final CloseableHttpClient client = HttpClientBuilder.create()
+            .setDefaultRequestConfig(requestConfig)
+            .build();
+
+        final HttpGet request = new HttpGet("http://www.github.com");
+
+        assertThrows(ConnectTimeoutException.class, () -> {
+            response = client.execute(request);
+        });
+    }
+
+
     @Test
     void whenSecuredRestApiIsConsumed_then200OK() throws IOException {
         CloseableHttpClient httpClient = HttpClientBuilder.create().build();

apache-httpclient4/src/test/java/com/baeldung/httpclient/advancedconfig/HttpClientAdvancedConfigurationIntegrationTest.java

@@ -1,7 +1,7 @@
 package com.baeldung.httpclient.advancedconfig;
 
+import com.github.tomakehurst.wiremock.WireMockServer;
 
-import com.github.tomakehurst.wiremock.junit.WireMockRule;
 import org.apache.http.HttpHeaders;
 import org.apache.http.HttpHost;
 import org.apache.http.HttpResponse;
@@ -19,8 +19,10 @@ import org.apache.http.impl.client.BasicAuthCache;
 import org.apache.http.impl.client.BasicCredentialsProvider;
 import org.apache.http.impl.client.HttpClients;
 import org.apache.http.impl.conn.DefaultProxyRoutePlanner;
-import org.junit.Rule;
+
-import org.junit.Test;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
 import java.io.IOException;
 
@@ -32,18 +34,29 @@ import static com.github.tomakehurst.wiremock.client.WireMock.getRequestedFor;
 import static com.github.tomakehurst.wiremock.client.WireMock.post;
 import static com.github.tomakehurst.wiremock.client.WireMock.urlEqualTo;
 import static com.github.tomakehurst.wiremock.client.WireMock.urlMatching;
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
-public class HttpClientAdvancedConfigurationIntegrationTest {
+class HttpClientAdvancedConfigurationIntegrationTest {
 
-    @Rule
+    public WireMockServer serviceMock;
-    public WireMockRule serviceMock = new WireMockRule(8089);
+    public WireMockServer proxyMock;
 
-    @Rule
+    @BeforeEach
-    public WireMockRule proxyMock = new WireMockRule(8090);
+    public void before () {
+        serviceMock = new WireMockServer(8089);
+        serviceMock.start();
+        proxyMock = new WireMockServer(8090);
+        proxyMock.start();
+    }
+
+    @AfterEach
+    public void after () {
+        serviceMock.stop();
+        proxyMock.stop();
+    }
 
     @Test
-    public void givenClientWithCustomUserAgentHeader_whenExecuteRequest_shouldReturn200() throws IOException {
+    void givenClientWithCustomUserAgentHeader_whenExecuteRequest_shouldReturn200() throws IOException {
         //given
         String userAgent = "BaeldungAgent/1.0";
         serviceMock.stubFor(get(urlEqualTo("/detail"))
@@ -59,11 +72,11 @@ public class HttpClientAdvancedConfigurationIntegrationTest {
         HttpResponse response = httpClient.execute(httpGet);
 
         //then
-        assertEquals(response.getStatusLine().getStatusCode(), 200);
+        assertEquals(200, response.getStatusLine().getStatusCode());
     }
 
     @Test
-    public void givenClientThatSendDataInBody_whenSendXmlInBody_shouldReturn200() throws IOException {
+    void givenClientThatSendDataInBody_whenSendXmlInBody_shouldReturn200() throws IOException {
         //given
         String xmlBody = "<xml><id>1</id></xml>";
         serviceMock.stubFor(post(urlEqualTo("/person"))
@@ -82,12 +95,11 @@ public class HttpClientAdvancedConfigurationIntegrationTest {
         HttpResponse response = httpClient.execute(httpPost);
 
         //then
-        assertEquals(response.getStatusLine().getStatusCode(), 200);
+        assertEquals(200, response.getStatusLine().getStatusCode());
-
     }
 
     @Test
-    public void givenServerThatIsBehindProxy_whenClientIsConfiguredToSendRequestViaProxy_shouldReturn200() throws IOException {
+    void givenServerThatIsBehindProxy_whenClientIsConfiguredToSendRequestViaProxy_shouldReturn200() throws IOException {
         //given
         proxyMock.stubFor(get(urlMatching(".*"))
           .willReturn(aResponse().proxiedFrom("http://localhost:8089/")));
@@ -107,13 +119,13 @@ public class HttpClientAdvancedConfigurationIntegrationTest {
         HttpResponse response = httpclient.execute(httpGet);
 
         //then
-        assertEquals(response.getStatusLine().getStatusCode(), 200);
+        assertEquals(200, response.getStatusLine().getStatusCode());
         proxyMock.verify(getRequestedFor(urlEqualTo("/private")));
         serviceMock.verify(getRequestedFor(urlEqualTo("/private")));
     }
 
     @Test
-    public void givenServerThatIsBehindAuthorizationProxy_whenClientSendRequest_shouldAuthorizeProperly() throws IOException {
+    void givenServerThatIsBehindAuthorizationProxy_whenClientSendRequest_shouldAuthorizeProperly() throws IOException {
         //given
         proxyMock.stubFor(get(urlMatching("/private"))
           .willReturn(aResponse().proxiedFrom("http://localhost:8089/")));
@@ -152,7 +164,7 @@ public class HttpClientAdvancedConfigurationIntegrationTest {
         HttpResponse response = httpclient.execute(httpGet, context);
 
         //then
-        assertEquals(response.getStatusLine().getStatusCode(), 200);
+        assertEquals(200, response.getStatusLine().getStatusCode());
         proxyMock.verify(getRequestedFor(urlEqualTo("/private")).withHeader("Authorization", containing("Basic")));
         serviceMock.verify(getRequestedFor(urlEqualTo("/private")));
     }

apache-httpclient4/src/test/java/com/baeldung/httpclient/expandurl/HttpClientExpandUrlLiveTest.java

@@ -12,34 +12,35 @@ import org.apache.http.client.methods.HttpHead;
 import org.apache.http.impl.client.CloseableHttpClient;
 import org.apache.http.impl.client.HttpClientBuilder;
 import org.apache.http.util.EntityUtils;
-import org.junit.Before;
+import org.junit.jupiter.api.BeforeEach;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.List;
 
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.equalTo;
-import static org.junit.Assert.assertThat;
 
-public class HttpClientExpandUrlLiveTest {
+
+class HttpClientExpandUrlLiveTest {
 
     private CloseableHttpClient client;
 
-    @Before
+    @BeforeEach
-    public final void before() {
+    public final void beforeEach() {
         client = HttpClientBuilder.create().disableRedirectHandling().build();
     }
 
     @Test
-    public final void givenShortenedOnce_whenUrlIsExpanded_thenCorrectResult() throws IOException {
+    final void givenShortenedOnce_whenUrlIsExpanded_thenCorrectResult() throws IOException {
         final String expectedResult = "https://www.baeldung.com/rest-versioning";
         final String actualResult = expandSingleLevel("http://bit.ly/3LScTri");
         assertThat(actualResult, equalTo(expectedResult));
     }
 
     @Test
-    public final void givenShortenedMultiple_whenUrlIsExpanded_thenCorrectResult() throws IOException {
+    final void givenShortenedMultiple_whenUrlIsExpanded_thenCorrectResult() throws IOException {
         final String expectedResult = "https://www.baeldung.com/rest-versioning";
         final String actualResult = expand("http://t.co/e4rDDbnzmk");
         assertThat(actualResult, equalTo(expectedResult));

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

@@ -17,7 +17,6 @@ import com.baeldung.GetRequestMockServer;
 
 class ApacheHttpClientUnitTest extends GetRequestMockServer {
 
-
     @Test
     void givenDeveloperUsedCloseableHttpResponse_whenExecutingGetRequest_thenStatusIsOk() throws IOException {
         try (CloseableHttpClient httpClient = HttpClientBuilder.create().build()) {

apache-httpclient4/src/test/java/com/baeldung/httpclient/httpclient/conn/HttpClientConnectionManagementLiveTest.java

@@ -1,7 +1,9 @@
 package com.baeldung.httpclient.httpclient.conn;
 
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import java.io.IOException;
 import java.util.concurrent.ExecutionException;
@@ -24,6 +26,7 @@ import org.apache.http.conn.ConnectionPoolTimeoutException;
 import org.apache.http.conn.ConnectionRequest;
 import org.apache.http.conn.routing.HttpRoute;
 import org.apache.http.impl.client.CloseableHttpClient;
+import org.apache.http.impl.client.HttpClientBuilder;
 import org.apache.http.impl.client.HttpClients;
 import org.apache.http.impl.conn.BasicHttpClientConnectionManager;
 import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
@@ -33,14 +36,14 @@ import org.apache.http.protocol.HttpContext;
 import org.apache.http.protocol.HttpCoreContext;
 import org.apache.http.protocol.HttpRequestExecutor;
 import org.apache.http.util.EntityUtils;
-import org.junit.Ignore;
+import org.junit.jupiter.api.Disabled;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
-public class HttpClientConnectionManagementLiveTest {
+class HttpClientConnectionManagementLiveTest {
 
     // Example 2.1. Getting a Connection Request for a Low Level Connection (HttpClientConnection)
     @Test
-    public final void whenLowLevelConnectionIsEstablished_thenNoExceptions() throws ConnectionPoolTimeoutException, InterruptedException, ExecutionException {
+    final void whenLowLevelConnectionIsEstablished_thenNoExceptions() throws ConnectionPoolTimeoutException, InterruptedException, ExecutionException {
         try (BasicHttpClientConnectionManager connManager = new BasicHttpClientConnectionManager()) {
             HttpRoute route = new HttpRoute(new HttpHost("www.baeldung.com", 80));
             final ConnectionRequest connRequest = connManager.requestConnection(route, null);
@@ -50,20 +53,20 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 3.1. Setting the PoolingHttpClientConnectionManager on a HttpClient
     @Test
-    public final void whenPollingConnectionManagerIsConfiguredOnHttpClient_thenNoExceptions() throws ClientProtocolException, IOException {
+    final void whenPollingConnectionManagerIsConfiguredOnHttpClient_thenNoExceptions() throws ClientProtocolException, IOException {
         PoolingHttpClientConnectionManager poolingConnManager = new PoolingHttpClientConnectionManager();
         CloseableHttpClient client = HttpClients.custom()
             .setConnectionManager(poolingConnManager)
             .build();
         client.execute(new HttpGet("https://www.baeldung.com"));
 
-        assertTrue(poolingConnManager.getTotalStats()
+        assertEquals(1, poolingConnManager.getTotalStats()
-            .getLeased() == 1);
+            .getLeased());
     }
 
     // Example 3.2. Using Two HttpClients to Connect to One Target Host Each
     @Test
-    public final void whenTwoConnectionsForTwoRequests_thenNoExceptions() throws InterruptedException {
+    final void whenTwoConnectionsForTwoRequests_thenNoExceptions() throws InterruptedException {
         HttpGet get1 = new HttpGet("https://www.baeldung.com");
         HttpGet get2 = new HttpGet("https://www.google.com");
         PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
@@ -81,13 +84,13 @@ public class HttpClientConnectionManagementLiveTest {
         thread1.join();
         thread2.join();
 
-        assertTrue(connManager.getTotalStats()
+        assertEquals(0, connManager.getTotalStats()
-            .getLeased() == 0);
+            .getLeased());
     }
 
     // Example 4.1. Increasing the Number of Connections that Can be Open and Managed Beyond the default Limits
     @Test
-    public final void whenIncreasingConnectionPool_thenNoEceptions() {
+    final void whenIncreasingConnectionPool_thenNoEceptions() {
         try (PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager()) {
             connManager.setMaxTotal(5);
             connManager.setDefaultMaxPerRoute(4);
@@ -98,7 +101,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 4.2. Using Threads to Execute Connections
     @Test
-    public final void whenExecutingSameRequestsInDifferentThreads_thenExecuteReuqest() throws InterruptedException {
+    final void whenExecutingSameRequestsInDifferentThreads_thenExecuteReuqest() throws InterruptedException {
         HttpGet get = new HttpGet("http://www.baeldung.com");
         PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
         CloseableHttpClient client = HttpClients.custom()
@@ -117,7 +120,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 5.1. A Custom Keep Alive Strategy
     @Test
-    public final void whenCustomizingKeepAliveStrategy_thenNoExceptions() {
+    final void whenCustomizingKeepAliveStrategy_thenNoExceptions() {
         final ConnectionKeepAliveStrategy myStrategy = new ConnectionKeepAliveStrategy() {
             @Override
             public long getKeepAliveDuration(final HttpResponse myResponse, final HttpContext myContext) {
@@ -148,7 +151,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 6.1. BasicHttpClientConnectionManager Connection Reuse
     @Test
-    public final void givenBasicHttpClientConnManager_whenConnectionReuse_thenNoExceptions() throws IOException, HttpException, InterruptedException, ExecutionException {
+    final void givenBasicHttpClientConnManager_whenConnectionReuse_thenNoExceptions() throws IOException, HttpException, InterruptedException, ExecutionException {
         BasicHttpClientConnectionManager basicConnManager = new BasicHttpClientConnectionManager();
         HttpClientContext context = HttpClientContext.create();
 
@@ -175,7 +178,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 6.2. PoolingHttpClientConnectionManager: Re-Using Connections with Threads
     @Test
-    public final void whenConnectionsNeededGreaterThanMaxTotal_thenLeaseMasTotalandReuse() throws InterruptedException {
+    final void whenConnectionsNeededGreaterThanMaxTotal_thenLeaseMasTotalandReuse() throws InterruptedException {
         HttpGet get = new HttpGet("http://echo.200please.com");
         PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
         connManager.setDefaultMaxPerRoute(5);
@@ -197,20 +200,20 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 7.1. Setting Socket Timeout to 5 Seconds
     @Test
-    public final void whenConfiguringTimeOut_thenNoExceptions() {
+    final void whenConfiguringTimeOut_thenNoExceptions() {
         HttpRoute route = new HttpRoute(new HttpHost("www.baeldung.com", 80));
         try (PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager()) {
             connManager.setSocketConfig(route.getTargetHost(), SocketConfig.custom()
                 .setSoTimeout(5000)
                 .build());
-            assertTrue(connManager.getSocketConfig(route.getTargetHost())
+            assertEquals(5000, connManager.getSocketConfig(route.getTargetHost())
-                .getSoTimeout() == 5000);
+                .getSoTimeout());
         }
     }
 
     // Example 8.1. Setting the HttpClient to Check for Stale Connections
     @Test
-    public final void whenHttpClientChecksStaleConns_thenNoExceptions() {
+    final void whenHttpClientChecksStaleConns_thenNoExceptions() {
         PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
         HttpClients.custom()
             .setDefaultRequestConfig(RequestConfig.custom()
@@ -222,7 +225,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     // Example 8.2. Using a Stale Connection Monitor Thread
     @Test
-    public final void whenCustomizedIdleConnMonitor_thenNoExceptions() throws InterruptedException {
+    final void whenCustomizedIdleConnMonitor_thenNoExceptions() throws InterruptedException {
         PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
         HttpClients.custom()
             .setConnectionManager(connManager)
@@ -233,8 +236,8 @@ public class HttpClientConnectionManagementLiveTest {
     }
 
     // Example 9.1. Closing Connection and Releasing Resources
-    @Test(expected = IllegalStateException.class)
+    @Test
-    public final void whenClosingConnectionsandManager_thenCloseWithNoExceptions1() throws InterruptedException, ExecutionException, IOException, HttpException {
+    final void whenClosingConnectionsAndManager_thenCloseWithNoExceptions1() throws IOException {
         PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager();
         CloseableHttpClient client = HttpClients.custom()
             .setConnectionManager(connManager)
@@ -248,14 +251,14 @@ public class HttpClientConnectionManagementLiveTest {
         connManager.close();
         connManager.shutdown();
 
-        client.execute(get);
+        assertThrows(IllegalStateException.class, () -> {
-
+            client.execute(get);
-        assertTrue(response.getEntity() == null);
+        });
     }
 
     @Test
     // Example 3.2. TESTER VERSION
-    public final void whenTwoConnectionsForTwoRequests_thenTwoConnectionsAreLeased() throws InterruptedException {
+    final void whenTwoConnectionsForTwoRequests_thenTwoConnectionsAreLeased() throws InterruptedException {
         HttpGet get1 = new HttpGet("https://www.baeldung.com");
         HttpGet get2 = new HttpGet("https://www.google.com");
 
@@ -273,13 +276,13 @@ public class HttpClientConnectionManagementLiveTest {
         thread2.start();
         thread1.join();
         thread2.join(1000);
-        assertTrue(poolingConnManager.getTotalStats()
+        assertEquals(2, poolingConnManager.getTotalStats()
-            .getLeased() == 2);
+            .getLeased());
     }
 
     @Test
     // Example 4.2 Tester Version
-    public final void whenExecutingSameRequestsInDifferentThreads_thenUseDefaultConnLimit() throws InterruptedException {
+    final void whenExecutingSameRequestsInDifferentThreads_thenUseDefaultConnLimit() throws InterruptedException {
         PoolingHttpClientConnectionManager poolingConnManager = new PoolingHttpClientConnectionManager();
         CloseableHttpClient client = HttpClients.custom()
             .setConnectionManager(poolingConnManager)
@@ -297,7 +300,7 @@ public class HttpClientConnectionManagementLiveTest {
 
     @Test
     // 6.2 TESTER VERSION
-    public final void whenConnectionsNeededGreaterThanMaxTotal_thenReuseConnections() throws InterruptedException {
+    final void whenConnectionsNeededGreaterThanMaxTotal_thenReuseConnections() throws InterruptedException {
         PoolingHttpClientConnectionManager poolingConnManager = new PoolingHttpClientConnectionManager();
         poolingConnManager.setDefaultMaxPerRoute(5);
         poolingConnManager.setMaxTotal(5);
@@ -316,15 +319,15 @@ public class HttpClientConnectionManagementLiveTest {
             thread.join(10000);
             countConnMade++;
             if (countConnMade == 0) {
-                assertTrue(thread.getLeasedConn() == 5);
+                assertEquals(5, thread.getLeasedConn());
             }
         }
     }
 
     @Test
-    @Ignore("Very Long Running")
+    @Disabled("Very Long Running")
     // 8.2 TESTER VERSION
-    public final void whenCustomizedIdleConnMonitor_thenEliminateIdleConns() throws InterruptedException {
+    final void whenCustomizedIdleConnMonitor_thenEliminateIdleConns() throws InterruptedException {
         PoolingHttpClientConnectionManager poolingConnManager = new PoolingHttpClientConnectionManager();
         CloseableHttpClient client = HttpClients.custom()
             .setConnectionManager(poolingConnManager)
@@ -340,10 +343,10 @@ public class HttpClientConnectionManagementLiveTest {
         thread2.start();
         thread2.join();
         thread3.start();
-        assertTrue(poolingConnManager.getTotalStats()
+        assertEquals(1, poolingConnManager.getTotalStats()
-            .getAvailable() == 1);
+            .getAvailable());
         thread3.join(32000);
-        assertTrue(poolingConnManager.getTotalStats()
+        assertEquals(0, poolingConnManager.getTotalStats()
-            .getAvailable() == 0);
+            .getAvailable());
     }
 }

apache-httpclient4/src/test/java/com/baeldung/httpclient/httpclient/conn/MultiHttpClientConnThread.java

@@ -3,7 +3,6 @@ package com.baeldung.httpclient.httpclient.conn;
 import java.io.IOException;
 
 import org.apache.http.HttpResponse;
-import org.apache.http.client.ClientProtocolException;
 import org.apache.http.client.methods.HttpGet;
 import org.apache.http.impl.client.CloseableHttpClient;
 import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;

apache-httpclient4/src/test/java/com/baeldung/httpclient/httpclient/conn/TesterVersion_MultiHttpClientConnThread.java

@@ -2,7 +2,6 @@ package com.baeldung.httpclient.httpclient.conn;
 
 import java.io.IOException;
 
-import org.apache.http.client.ClientProtocolException;
 import org.apache.http.client.methods.HttpGet;
 import org.apache.http.impl.client.CloseableHttpClient;
 import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;

apache-httpclient4/src/test/java/com/baeldung/httpclient/readresponsebodystring/ApacheHttpClientUnitTest.java

@@ -6,18 +6,19 @@ import org.apache.http.client.methods.HttpGet;
 import org.apache.http.impl.client.CloseableHttpClient;
 import org.apache.http.impl.client.HttpClients;
 import org.apache.http.util.EntityUtils;
-import org.junit.Test;
+
+import org.junit.jupiter.api.Test;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
 
-public class ApacheHttpClientUnitTest {
+class ApacheHttpClientUnitTest {
     private final Logger logger = LoggerFactory.getLogger(this.getClass());
     public static final String DUMMY_URL = "https://postman-echo.com/get";
 
     @Test
-    public void whenUseApacheHttpClient_thenCorrect() throws IOException {
+    void whenUseApacheHttpClient_thenCorrect() throws IOException {
         HttpGet request = new HttpGet(DUMMY_URL);
 
         try (CloseableHttpClient client = HttpClients.createDefault(); CloseableHttpResponse response = client.execute(request)) {

apache-httpclient4/src/test/java/com/baeldung/httpclient/retry/ApacheHttpClientRetryLiveTest.java

@@ -24,7 +24,7 @@ import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-public class ApacheHttpClientRetryLiveTest {
+class ApacheHttpClientRetryLiveTest {
 
     private Integer requestCounter;
     private CloseableHttpClient httpClient;
@@ -93,14 +93,14 @@ public class ApacheHttpClientRetryLiveTest {
     }
 
     @Test
-    public void givenDefaultConfiguration_whenReceivedIOException_thenRetriesPerformed() {
+    void givenDefaultConfiguration_whenReceivedIOException_thenRetriesPerformed() {
         createFailingHttpClient();
         assertThrows(IOException.class, () -> httpClient.execute(new HttpGet("https://httpstat.us/200")));
         assertThat(requestCounter).isEqualTo(4);
     }
 
     @Test
-    public void givenDefaultConfiguration_whenDomainNameNotResolved_thenNoRetryApplied() {
+    void givenDefaultConfiguration_whenDomainNameNotResolved_thenNoRetryApplied() {
         createDefaultApacheHttpClient();
         HttpGet request = new HttpGet(URI.create("http://domain.that.does.not.exist:80/api/v1"));
 
@@ -109,7 +109,7 @@ public class ApacheHttpClientRetryLiveTest {
     }
 
     @Test
-    public void givenDefaultConfiguration_whenGotInternalServerError_thenNoRetryLogicApplied() throws IOException {
+    void givenDefaultConfiguration_whenGotInternalServerError_thenNoRetryLogicApplied() throws IOException {
         createDefaultApacheHttpClient();
         HttpGet request = new HttpGet(URI.create("https://httpstat.us/500"));
 
@@ -120,7 +120,7 @@ public class ApacheHttpClientRetryLiveTest {
     }
 
     @Test
-    public void givenDefaultConfiguration_whenHttpPatchRequest_thenRetryIsNotApplied() {
+    void givenDefaultConfiguration_whenHttpPatchRequest_thenRetryIsNotApplied() {
         createFailingHttpClient();
         HttpPatch request = new HttpPatch(URI.create("https://httpstat.us/500"));
 
@@ -129,7 +129,7 @@ public class ApacheHttpClientRetryLiveTest {
     }
 
     @Test
-    public void givenDefaultConfiguration_whenHttpPutRequest_thenRetryIsNotApplied() {
+    void givenDefaultConfiguration_whenHttpPutRequest_thenRetryIsNotApplied() {
         createFailingHttpClient();
         HttpPut request = new HttpPut(URI.create("https://httpstat.us/500"));
 
@@ -138,7 +138,7 @@ public class ApacheHttpClientRetryLiveTest {
     }
 
     @Test
-    public void givenConfiguredRetryHandler_whenHttpPostRequest_thenRetriesPerformed() {
+    void givenConfiguredRetryHandler_whenHttpPostRequest_thenRetriesPerformed() {
         createHttpClientWithRetryHandler();
 
         HttpPost request = new HttpPost(URI.create("https://httpstat.us/200"));
@@ -148,7 +148,7 @@ public class ApacheHttpClientRetryLiveTest {
     }
 
     @Test
-    public void givenCustomRetryHandler_whenUnknownHostException_thenRetryAnyway() {
+    void givenCustomRetryHandler_whenUnknownHostException_thenRetryAnyway() {
         createHttpClientWithCustomRetryHandler();
 
         HttpGet request = new HttpGet(URI.create("https://domain.that.does.not.exist/200"));
@@ -158,7 +158,7 @@ public class ApacheHttpClientRetryLiveTest {
     }
 
     @Test
-    public void givenDisabledRetries_whenExecutedHttpRequestEndUpWithIOException_thenRetryIsNotApplied() {
+    void givenDisabledRetries_whenExecutedHttpRequestEndUpWithIOException_thenRetryIsNotApplied() {
         createHttpClientWithRetriesDisabled();
         HttpGet request = new HttpGet(URI.create("https://httpstat.us/200"));
 

apache-libraries-2/README.md

@@ -0,0 +1,2 @@
+## Relevant Articles
+- [Understanding XSLT Processing in Java](https://www.baeldung.com/java-extensible-stylesheet-language-transformations)

apache-libraries-2/pom.xml

@@ -21,7 +21,6 @@
         </dependency>
     </dependencies>
 
-
     <properties>
         <javax.validation.validation-api.version>2.0.1.Final</javax.validation.validation-api.version>
     </properties>

apache-libraries-2/src/main/java/com/baeldung/xsltProcessing/XSLTProcessorWithParametersAndOption.java

@@ -0,0 +1,31 @@
+package com.baeldung.xsltProcessing;
+
+import javax.xml.transform.*;
+import javax.xml.transform.stream.StreamResult;
+import javax.xml.transform.stream.StreamSource;
+import java.io.File;
+
+public class XSLTProcessorWithParametersAndOption {
+    public static void transformXMLWithParametersAndOption(
+            String inputXMLPath,
+            String xsltPath,
+            String outputHTMLPath,
+            String companyName,
+            boolean enableIndentation
+    ) throws TransformerException {
+        TransformerFactory transformerFactory = TransformerFactory.newInstance();
+        Source xsltSource = new StreamSource(new File(xsltPath));
+        Transformer transformer = transformerFactory.newTransformer(xsltSource);
+
+        transformer.setParameter("companyName", companyName);
+
+        if (enableIndentation) {
+            transformer.setOutputProperty(OutputKeys.INDENT, "yes");
+        }
+
+        Source xmlSource = new StreamSource(new File(inputXMLPath));
+        Result outputResult = new StreamResult(new File(outputHTMLPath));
+
+        transformer.transform(xmlSource, outputResult);
+    }
+}

apache-libraries-2/src/main/java/com/baeldung/xsltProcessing/XSLTProcessorWithTemplate.java

@@ -0,0 +1,21 @@
+package com.baeldung.xsltProcessing;
+
+import javax.xml.transform.*;
+import javax.xml.transform.stream.StreamResult;
+import javax.xml.transform.stream.StreamSource;
+import java.io.File;
+
+public class XSLTProcessorWithTemplate {
+    public static void transformXMLUsingTemplate(String inputXMLPath, String xsltPath, String outputHTMLPath) throws TransformerException {
+        TransformerFactory transformerFactory = TransformerFactory.newInstance();
+        Source xsltSource = new StreamSource(new File(xsltPath));
+        Templates templates = transformerFactory.newTemplates(xsltSource);
+
+        Transformer transformer = templates.newTransformer();
+
+        Source xmlSource = new StreamSource(new File(inputXMLPath));
+        Result outputResult = new StreamResult(new File(outputHTMLPath));
+
+        transformer.transform(xmlSource, outputResult);
+    }
+}

apache-velocity/pom.xml

@@ -63,7 +63,6 @@
         <org.apache.httpcomponents.version>4.5.2</org.apache.httpcomponents.version>
         <velocity-version>1.7</velocity-version>
         <velocity-tools-version>2.0</velocity-tools-version>
-        <maven-war-plugin.version>3.3.2</maven-war-plugin.version>
     </properties>
 
 </project>

asm/pom.xml

@@ -49,7 +49,6 @@
 
     <properties>
         <asm.version>5.2</asm.version>
-        <maven-jar-plugin.version>2.4</maven-jar-plugin.version>
     </properties>
 
 </project>

aws-modules/aws-s3-update-object/pom.xml

@@ -1,6 +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"
+<project xmlns="http://maven.apache.org/POM/4.0.0"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
     <artifactId>aws-s3-update-object</artifactId>
     <version>0.0.1-SNAPSHOT</version>

aws-modules/aws-s3/README.md

@@ -8,4 +8,6 @@ This module contains articles about Simple Storage Service (S3) on AWS
 - [Multipart Uploads in Amazon S3 with Java](https://www.baeldung.com/aws-s3-multipart-upload)
 - [Using the JetS3t Java Client With Amazon S3](https://www.baeldung.com/jets3t-amazon-s3)
 - [Check if a Specified Key Exists in a Given S3 Bucket Using Java](https://www.baeldung.com/java-aws-s3-check-specified-key-exists)
-- [Listing All AWS S3 Objects in a Bucket Using Java](https://www.baeldung.com/java-aws-s3-list-bucket-objects) 
+- [Listing All AWS S3 Objects in a Bucket Using Java](https://www.baeldung.com/java-aws-s3-list-bucket-objects)
+- [Update an Existing Amazon S3 Object Using Java](https://www.baeldung.com/java-update-amazon-s3-object)
+- [How To Rename Files and Folders in Amazon S3](https://www.baeldung.com/java-amazon-s3-rename-files-folders)

aws-modules/aws-s3/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"
+    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">
+    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>aws-s3</artifactId>
     <version>0.1.0-SNAPSHOT</version>

aws-modules/aws-s3/src/main/java/com/baeldung/s3/RenameObjectService.java

@@ -0,0 +1,79 @@
+package com.baeldung.s3;
+
+import java.util.List;
+
+import software.amazon.awssdk.auth.credentials.ProfileCredentialsProvider;
+import software.amazon.awssdk.regions.Region;
+import software.amazon.awssdk.services.s3.S3Client;
+import software.amazon.awssdk.services.s3.model.CopyObjectRequest;
+import software.amazon.awssdk.services.s3.model.DeleteObjectRequest;
+import software.amazon.awssdk.services.s3.model.ListObjectsV2Request;
+import software.amazon.awssdk.services.s3.model.ListObjectsV2Response;
+import software.amazon.awssdk.services.s3.model.S3Object;
+
+public class RenameObjectService {
+
+    private S3Client s3Client;
+
+    public RenameObjectService(S3Client s3Client) {
+        this.s3Client = s3Client;
+    }
+
+    public RenameObjectService() {
+        init();
+    }
+
+    public void init() {
+        this.s3Client = S3Client.builder()
+          .region(Region.US_EAST_1)
+          .credentialsProvider(ProfileCredentialsProvider.create("default"))
+          .build();
+    }
+
+    public void renameFile(String bucketName, String keyName, String destinationKeyName) {
+        CopyObjectRequest copyObjRequest = CopyObjectRequest.builder()
+          .sourceBucket(bucketName)
+          .sourceKey(keyName)
+          .destinationBucket(destinationKeyName)
+          .destinationKey(bucketName)
+          .build();
+        s3Client.copyObject(copyObjRequest);
+        DeleteObjectRequest deleteRequest = DeleteObjectRequest.builder()
+          .bucket(bucketName)
+          .key(keyName)
+          .build();
+        s3Client.deleteObject(deleteRequest);
+    }
+
+    public void renameFolder(String bucketName, String sourceFolderKey, String destinationFolderKey) {
+        ListObjectsV2Request listRequest = ListObjectsV2Request.builder()
+          .bucket(bucketName)
+          .prefix(sourceFolderKey)
+          .build();
+
+        ListObjectsV2Response listResponse = s3Client.listObjectsV2(listRequest);
+        List<S3Object> objects = listResponse.contents();
+
+        for (S3Object s3Object : objects) {
+            String newKey = destinationFolderKey + s3Object.key()
+              .substring(sourceFolderKey.length());
+
+            // Copy object to destination folder
+            CopyObjectRequest copyRequest = CopyObjectRequest.builder()
+              .sourceBucket(bucketName)
+              .sourceKey(s3Object.key())
+              .destinationBucket(bucketName)
+              .destinationKey(newKey)
+              .build();
+            s3Client.copyObject(copyRequest);
+
+            // Delete object from source folder
+            DeleteObjectRequest deleteRequest = DeleteObjectRequest.builder()
+              .bucket(bucketName)
+              .key(s3Object.key())
+              .build();
+            s3Client.deleteObject(deleteRequest);
+        }
+    }
+
+}

azure/pom.xml

@@ -122,7 +122,6 @@
         <docker.image.prefix>${azure.containerRegistry}.azurecr.io</docker.image.prefix>
         <docker-maven-plugin.version>1.1.0</docker-maven-plugin.version>
         <azure-webapp-maven-plugin.version>1.1.0</azure-webapp-maven-plugin.version>
-        <maven-war-plugin.version>3.3.2</maven-war-plugin.version>
     </properties>
 
 </project>

core-groovy-modules/pom.xml

@@ -27,6 +27,7 @@
         <hsqldb.version>2.7.1</hsqldb.version>
         <spock-core.version>2.3-groovy-3.0</spock-core.version>
         <gmavenplus-plugin.version>2.1.0</gmavenplus-plugin.version>
+        <maven-failsafe-plugin.version>2.21.0</maven-failsafe-plugin.version>
     </properties>
 
 </project>

core-java-modules/Reminder Application/Reminder Application/task/src/reminderapplication/ConstraintsBuilder.java

@@ -1,15 +0,0 @@
-package reminderapplication;
-
-import java.awt.GridBagConstraints;
-import java.awt.Insets;
-
-public class ConstraintsBuilder {
-
-    static GridBagConstraints constraint(int x, int y) {
-        final GridBagConstraints gridBagConstraints = new GridBagConstraints();
-        gridBagConstraints.gridx = x;
-        gridBagConstraints.gridy = y;
-        gridBagConstraints.insets = new Insets(5, 5, 5, 5);
-        return gridBagConstraints;
-    }
-}

core-java-modules/Reminder Application/Reminder Application/task/src/reminderapplication/EditReminderFrame.java

@@ -1,194 +0,0 @@
-package reminderapplication;
-
-import static reminderapplication.ConstraintsBuilder.*;
-
-import java.awt.GridBagLayout;
-import java.awt.HeadlessException;
-import java.lang.reflect.InvocationTargetException;
-import java.util.Timer;
-import java.util.TimerTask;
-import java.util.concurrent.TimeUnit;
-import javax.swing.DefaultComboBoxModel;
-import javax.swing.DefaultListModel;
-import javax.swing.JButton;
-import javax.swing.JComboBox;
-import javax.swing.JFrame;
-import javax.swing.JLabel;
-import javax.swing.JTextField;
-import javax.swing.SwingUtilities;
-
-public class EditReminderFrame extends JFrame {
-
-    private static Timer TIMER = new Timer();
-
-    private final TimeReminderApplication reminderApplication;
-    private final JLabel reminderTextLabel;
-    private final JLabel repeatPeriodLabel;
-    private final JLabel setDelayLabel;
-    private final JComboBox<Integer> delay;
-    private final JComboBox<Integer> period;
-    private final JButton cancelButton;
-    private final JButton okButton;
-    private final JTextField textField;
-    private final JLabel delaysLabel;
-    private final JLabel periodLabel;
-
-    private final int reminderIndex;
-
-    public EditReminderFrame(TimeReminderApplication reminderApp, String reminderText, int delayInSeconds, int periodInSeconds, int index) throws HeadlessException {
-        this.reminderApplication = reminderApp;
-        reminderIndex = index;
-        textField = createTextField(reminderText);
-        delay = createDelayComboBox(delayInSeconds);
-        period = createPeriodComboBox(periodInSeconds);
-        cancelButton = createCancelButton();
-        okButton = createOkButton();
-        reminderTextLabel = createReminderTextLabel();
-        repeatPeriodLabel = createRepeatPeriodLabel();
-        setDelayLabel = createSetDelayLabel();
-        delaysLabel = createDelaysLabel();
-        periodLabel = createPeriodLabel();
-        configureVisualRepresentation();
-        configureActions();
-    }
-
-    private void configureActions() {
-        updateReminder();
-    }
-
-    private void configureVisualRepresentation() {
-        configureFrame();
-        setLocationRelativeTo(null);
-        setLayout(new GridBagLayout());
-        add(reminderTextLabel, constraint(0,0));
-        add(repeatPeriodLabel, constraint(1,0));
-        add(setDelayLabel, constraint(2,0));
-        add(textField, constraint(0, 1));
-        add(delay, constraint(1, 1));
-        add(period, constraint(2, 1));
-        add(delaysLabel, constraint(1,3));
-        add(periodLabel, constraint(2,3));
-        add(okButton, constraint(1, 4));
-        add(cancelButton, constraint(2, 4));
-        pack();
-        setVisible(true);
-    }
-
-    private void configureFrame() {
-        setTitle("Set Reminder");
-        setName("Set Reminder");
-        setDefaultCloseOperation(DISPOSE_ON_CLOSE);
-    }
-
-    private static JLabel createSetDelayLabel() {
-        return createLabel("Set Delay", "Set Delay Label");
-    }
-
-    private static JLabel createRepeatPeriodLabel() {
-        return createLabel("Set Period", "Set Repeat Period Label");
-    }
-
-    private static JLabel createReminderTextLabel() {
-        return createLabel("Reminder Text", "Reminder Text Label");
-    }
-
-    private JLabel createPeriodLabel() {
-        return createLabel("0", "Period label");
-    }
-
-    private JLabel createDelaysLabel() {
-        return createLabel("30", "Delays Label");
-    }
-
-    private JComboBox<Integer> createPeriodComboBox(final int periodInSeconds) {
-        final JComboBox<Integer> comboBox = new JComboBox<>(new DefaultComboBoxModel<>(new Integer[]{0, 5, 10, 20}));
-        comboBox.setSelectedItem(periodInSeconds);
-        comboBox.setName("set Period");
-        comboBox.addActionListener(e -> periodLabel.setText(comboBox.getSelectedItem().toString()));
-        return comboBox;
-    }
-
-    private JComboBox<Integer> createDelayComboBox(final int delayInSeconds) {
-        final JComboBox<Integer> comboBox = new JComboBox<>(new DefaultComboBoxModel<>(new Integer[]{30, 25, 15, 5}));
-        comboBox.setSelectedItem(delayInSeconds);
-        comboBox.setName("set Delay");
-        comboBox.addActionListener(e -> delaysLabel.setText(comboBox.getSelectedItem().toString()));
-        return comboBox;
-    }
-
-    private JTextField createTextField(final String reminderText) {
-        final JTextField textField = new JTextField(20);
-        textField.setName("Field");
-        textField.setText(reminderText);
-        return textField;
-    }
-
-    private JButton createOkButton() {
-        final JButton button = new JButton("ok");
-        button.setName("OK");
-        return button;
-    }
-
-    private void updateReminder() {
-        okButton.addActionListener(e -> this.dispose());
-        okButton.addActionListener(e -> {
-            final int periodInSeconds = getTimeInSeconds(period);
-            final int delayInSeconds = getTimeInSeconds(delay);
-            final Reminder reminder = new Reminder(textField.getText(), delayInSeconds, periodInSeconds);
-            ((DefaultListModel<Reminder>) reminderApplication.getReminders()).set(reminderIndex, reminder);
-        });
-        okButton.addActionListener(e -> scheduleReminder(textField, delay, period));
-    }
-
-    private void scheduleReminder(final JTextField textField, final JComboBox<Integer> delay, final JComboBox<Integer> period) {
-        final int periodInSeconds = getTimeInSeconds(period);
-        if (periodInSeconds == 0)
-            scheduleNonRepeatedReminder(textField, delay);
-        else
-            scheduleRepeatedReminder(textField, delay, period);
-    }
-
-    private void scheduleRepeatedReminder(final JTextField textField, final JComboBox<Integer> delay, final JComboBox<Integer> period) {
-        final int delayInSeconds = getTimeInSeconds(delay);
-        final int periodInSeconds = getTimeInSeconds(period);
-        final TimerTask timerTask = getTimerTask(textField.getText(), delayInSeconds, periodInSeconds);
-        TIMER.schedule(timerTask, TimeUnit.SECONDS.toMillis(delayInSeconds), TimeUnit.SECONDS.toMillis(periodInSeconds));
-    }
-
-    private void scheduleNonRepeatedReminder(final JTextField textField, final JComboBox<Integer> delay) {
-        final int delayInSeconds = getTimeInSeconds(delay);
-        final int periodInSeconds = 0;
-        final TimerTask timerTask = getTimerTask(textField.getText(), delayInSeconds, periodInSeconds);
-        TIMER.schedule(timerTask, TimeUnit.SECONDS.toMillis(delayInSeconds));
-
-    }
-
-    private int getTimeInSeconds(final JComboBox<Integer> comboBox) {
-        if (comboBox != null && comboBox.getSelectedItem() != null)
-            return ((Integer) comboBox.getSelectedItem());
-        else
-            return 0;
-    }
-
-    private TimerTask getTimerTask(final String reminderText, final Integer delayInSeconds, final Integer periodInSeconds) {
-        return new TimerTask() {
-            @Override
-            public void run() {
-                new ReminderPopupFrame(reminderApplication, reminderText, delayInSeconds, periodInSeconds);
-            }
-        };
-    }
-
-    private JButton createCancelButton() {
-        final JButton button = new JButton("cancel");
-        button.setName("Cancel");
-        button.addActionListener(e -> this.dispose());
-        return button;
-    }
-
-    private static JLabel createLabel(final String text, final String name) {
-        JLabel label = new JLabel(text);
-        label.setName(name);
-        return label;
-    }
-}

core-java-modules/Reminder Application/Reminder Application/task/src/reminderapplication/Reminder.java

@@ -1,33 +0,0 @@
-package reminderapplication;
-
-public class Reminder {
-
-    private static String REMINDER_FORMAT = "Reminder Text: %s; Delay: %d; Period: %d;";
-
-    private final String name;
-    private final int delay;
-    private final int period;
-
-    public Reminder(final String name, final int delay, final int period) {
-        this.name = name;
-        this.delay = delay;
-        this.period = period;
-    }
-
-    public String getName() {
-        return name;
-    }
-
-    public int getDelay() {
-        return delay;
-    }
-
-    public int getPeriod() {
-        return period;
-    }
-
-    @Override
-    public String toString() {
-        return REMINDER_FORMAT.formatted(name, delay, period);
-    }
-}

core-java-modules/Reminder Application/Reminder Application/task/src/reminderapplication/ReminderFrame.java

@@ -1,186 +0,0 @@
-package reminderapplication;
-
-import static reminderapplication.ConstraintsBuilder.*;
-
-import java.awt.GridBagLayout;
-import java.awt.HeadlessException;
-import java.util.Timer;
-import java.util.TimerTask;
-import java.util.concurrent.TimeUnit;
-import javax.swing.DefaultComboBoxModel;
-import javax.swing.DefaultListModel;
-import javax.swing.JButton;
-import javax.swing.JComboBox;
-import javax.swing.JFrame;
-import javax.swing.JLabel;
-import javax.swing.JTextField;
-
-public class ReminderFrame extends JFrame {
-
-    private static Timer TIMER = new Timer();
-    private final TimeReminderApplication reminderApplication;
-    private final JLabel reminderTextLabel;
-    private final JLabel repeatPeriodLabel;
-    private final JLabel setDelayLabel;
-    private final JComboBox<Integer> delay;
-    private final JComboBox<Integer> period;
-    private final JButton cancelButton;
-    private final JButton okButton;
-    private final JTextField textField;
-    private final JLabel delaysLabel;
-    private final JLabel periodLabel;
-
-    public ReminderFrame(TimeReminderApplication reminderApp) throws HeadlessException {
-        this.reminderApplication = reminderApp;
-        textField = createTextField();
-        delay = createDelayComboBox();
-        period = createPeriodComboBox();
-        cancelButton = createCancelButton();
-        okButton = createOkButton();
-        reminderTextLabel = createReminderTextLabel();
-        repeatPeriodLabel = createRepeatPeriodLabel();
-        setDelayLabel = createSetDelayLabel();
-        delaysLabel = createDelaysLabel();
-        periodLabel = createPeriodLabel();
-        configureVisualRepresentation();
-        configureActions();
-    }
-
-    private void configureActions() {
-        createNewReminder();
-    }
-
-    private void configureVisualRepresentation() {
-        configureFrame();
-        setLocationRelativeTo(null);
-        setLayout(new GridBagLayout());
-        add(reminderTextLabel, constraint(0,0));
-        add(repeatPeriodLabel, constraint(1,0));
-        add(setDelayLabel, constraint(2,0));
-        add(textField, constraint(0, 1));
-        add(delay, constraint(1, 1));
-        add(period, constraint(2, 1));
-        add(delaysLabel, constraint(1,3));
-        add(periodLabel, constraint(2,3));
-        add(okButton, constraint(1, 4));
-        add(cancelButton, constraint(2, 4));
-        pack();
-        setVisible(true);
-    }
-
-    private void configureFrame() {
-        setTitle("Set Reminder");
-        setName("Set Reminder");
-        setDefaultCloseOperation(DISPOSE_ON_CLOSE);
-    }
-
-    private static JLabel createSetDelayLabel() {
-        return createLabel("Set Delay", "Set Delay Label");
-    }
-
-    private static JLabel createRepeatPeriodLabel() {
-        return createLabel("Set Period", "Set Repeat Period Label");
-    }
-
-    private static JLabel createReminderTextLabel() {
-        return createLabel("Reminder Text", "Reminder Text Label");
-    }
-
-    private JLabel createPeriodLabel() {
-        return createLabel("0", "Period label");
-    }
-
-    private JLabel createDelaysLabel() {
-        return createLabel("30", "Delays Label");
-    }
-
-    private JComboBox<Integer> createPeriodComboBox() {
-        final JComboBox<Integer> comboBox = new JComboBox<>(new DefaultComboBoxModel<>(new Integer[]{0, 5, 10, 20}));
-        comboBox.setName("set Period");
-        comboBox.addActionListener(e -> periodLabel.setText(comboBox.getSelectedItem().toString()));
-        return comboBox;
-    }
-
-    private JComboBox<Integer> createDelayComboBox() {
-        final JComboBox<Integer> comboBox = new JComboBox<>(new DefaultComboBoxModel<>(new Integer[]{30, 25, 15, 5}));
-        comboBox.setName("set Delay");
-        comboBox.addActionListener(e -> delaysLabel.setText(comboBox.getSelectedItem().toString()));
-        return comboBox;
-    }
-
-    private JTextField createTextField() {
-        final JTextField textField = new JTextField(20);
-        textField.setName("Field");
-        return textField;
-    }
-
-    private JButton createOkButton() {
-        final JButton button = new JButton("ok");
-        button.setName("OK");
-        return button;
-    }
-
-    private void createNewReminder() {
-
-        okButton.addActionListener(e -> this.dispose());
-        okButton.addActionListener(e -> {
-            final int periodInSeconds = getTimeInSeconds(period);
-            final int delayInSeconds = getTimeInSeconds(delay);
-            final Reminder reminder = new Reminder(textField.getText(), delayInSeconds, periodInSeconds);
-            ((DefaultListModel<Reminder>) reminderApplication.getReminders()).addElement(reminder);
-        });
-        okButton.addActionListener(e -> scheduleReminder(textField, delay, period));
-    }
-
-    private void scheduleReminder(final JTextField textField, final JComboBox<Integer> delay, final JComboBox<Integer> period) {
-        final int periodInSeconds = getTimeInSeconds(period);
-        if (periodInSeconds == 0)
-            scheduleNonRepeatedReminder(textField, delay);
-        else
-            scheduleRepeatedReminder(textField, delay, period);
-    }
-
-    private void scheduleRepeatedReminder(final JTextField textField, final JComboBox<Integer> delay, final JComboBox<Integer> period) {
-        final int delayInSeconds = getTimeInSeconds(delay) + 200;
-        final int periodInSeconds = getTimeInSeconds(period);
-        final TimerTask timerTask = getTimerTask(textField.getText(), delayInSeconds, periodInSeconds);
-        TIMER.schedule(timerTask, TimeUnit.SECONDS.toMillis(delayInSeconds), TimeUnit.SECONDS.toMillis(periodInSeconds));
-    }
-
-    private void scheduleNonRepeatedReminder(final JTextField textField, final JComboBox<Integer> delay) {
-        final int delayInSeconds = getTimeInSeconds(delay);
-        final int periodInSeconds = 0;
-        final TimerTask timerTask = getTimerTask(textField.getText(), delayInSeconds, periodInSeconds);
-        TIMER.schedule(timerTask, TimeUnit.SECONDS.toMillis(delayInSeconds));
-
-    }
-
-    private int getTimeInSeconds(final JComboBox<Integer> comboBox) {
-        if (comboBox != null && comboBox.getSelectedItem() != null)
-            return ((Integer) comboBox.getSelectedItem());
-        else
-            return 0;
-    }
-
-    private TimerTask getTimerTask(final String reminderText, final Integer delayInSeconds, final Integer periodInSeconds) {
-        return new TimerTask() {
-            @Override
-            public void run() {
-                new ReminderPopupFrame(reminderApplication, reminderText, delayInSeconds, periodInSeconds);
-            }
-        };
-    }
-
-    private JButton createCancelButton() {
-        final JButton button = new JButton("cancel");
-        button.setName("Cancel");
-        button.addActionListener(e -> this.dispose());
-        return button;
-    }
-
-    private static JLabel createLabel(final String text, final String name) {
-        JLabel label = new JLabel(text);
-        label.setName(name);
-        return label;
-    }
-}

core-java-modules/Reminder Application/Reminder Application/task/src/reminderapplication/ReminderPopupFrame.java

@@ -1,151 +0,0 @@
-package reminderapplication;
-
-import static reminderapplication.ConstraintsBuilder.*;
-
-import java.awt.GridBagLayout;
-import java.awt.HeadlessException;
-import java.util.Timer;
-import java.util.TimerTask;
-import java.util.concurrent.TimeUnit;
-import javax.swing.DefaultComboBoxModel;
-import javax.swing.DefaultListModel;
-import javax.swing.JButton;
-import javax.swing.JComboBox;
-import javax.swing.JFrame;
-import javax.swing.JLabel;
-import javax.swing.JTextField;
-
-public class ReminderPopupFrame extends JFrame {
-
-    private static final Timer TIMER = new Timer();
-    private final int AUTOMATIC_CLOSE_TIME_IN_SECONDS = 10;
-    private final TimeReminderApplication reminderApplication;
-    private final JLabel reminderTextLabel;
-    private final JLabel repeatPeriodLabel;
-    private final JLabel setDelayLabel;
-    private final JComboBox<Integer> delay;
-    private final JComboBox<Integer> period;
-    private final JButton cancelButton;
-    private final JButton okButton;
-    private final JTextField textField;
-    private final JLabel delaysLabel;
-    private final JLabel periodLabel;
-
-    public ReminderPopupFrame(TimeReminderApplication reminderApp, final String text, final Integer delayInSeconds, final Integer periodInSeconds) throws HeadlessException {
-        this.reminderApplication = reminderApp;
-        textField = createTextField(text);
-        delay = createDelayComboBox(delayInSeconds);
-        period = createPeriodComboBox(periodInSeconds);
-        cancelButton = createCancelButton();
-        okButton = createDisabledOkButton();
-        reminderTextLabel = createReminderTextLabel();
-        repeatPeriodLabel = createRepeatPeriodLabel();
-        setDelayLabel = createSetDelayLabel();
-        delaysLabel = createDelaysLabel();
-        periodLabel = createPeriodLabel();
-        configureVisualRepresentation();
-        configureActions();
-    }
-
-    private void configureActions() {
-        scheduleClosing();
-    }
-
-    private void scheduleClosing() {
-        final TimerTask timerTask = new TimerTask() {
-            @Override
-            public void run() {
-                ReminderPopupFrame.this.dispose();
-            }
-        };
-        TIMER.schedule(timerTask, TimeUnit.SECONDS.toMillis(AUTOMATIC_CLOSE_TIME_IN_SECONDS));
-    }
-
-    private void configureVisualRepresentation() {
-        configureFrame();
-        setLocationRelativeTo(null);
-        setLayout(new GridBagLayout());
-        add(reminderTextLabel, constraint(0,0));
-        add(repeatPeriodLabel, constraint(1,0));
-        add(setDelayLabel, constraint(2,0));
-        add(textField, constraint(0, 1));
-        add(delay, constraint(1, 1));
-        add(period, constraint(2, 1));
-        add(delaysLabel, constraint(1,3));
-        add(periodLabel, constraint(2,3));
-        add(okButton, constraint(1, 4));
-        add(cancelButton, constraint(2, 4));
-        pack();
-        setVisible(true);
-    }
-
-    private void configureFrame() {
-        setTitle("Set Reminder");
-        setName("Set Reminder");
-        setDefaultCloseOperation(DISPOSE_ON_CLOSE);
-    }
-
-    private static JLabel createSetDelayLabel() {
-        return createLabel("Set Delay", "Set Delay Label");
-    }
-
-    private static JLabel createRepeatPeriodLabel() {
-        return createLabel("Set Period", "Set Repeat Period Label");
-    }
-
-    private static JLabel createReminderTextLabel() {
-        return createLabel("Reminder Text", "Reminder Text Label");
-    }
-
-    private JLabel createPeriodLabel() {
-        return createLabel("0", "Period label");
-    }
-
-    private JLabel createDelaysLabel() {
-        return createLabel("30", "Delays Label");
-    }
-
-    private JComboBox<Integer> createPeriodComboBox(final Integer periodInSeconds) {
-        final JComboBox<Integer> comboBox = new JComboBox<>(new DefaultComboBoxModel<>(new Integer[]{0, 5, 10, 20}));
-        comboBox.setName("set Period");
-        comboBox.setSelectedItem(periodInSeconds);
-        comboBox.addActionListener(e -> periodLabel.setText(comboBox.getSelectedItem().toString()));
-        return comboBox;
-    }
-
-    private JComboBox<Integer> createDelayComboBox(Integer delay) {
-        final JComboBox<Integer> comboBox = new JComboBox<>(new DefaultComboBoxModel<>(new Integer[]{30, 25, 15, 5}));
-        comboBox.setSelectedItem(delay);
-        comboBox.setName("set Delay");
-        comboBox.addActionListener(e -> delaysLabel.setText(comboBox.getSelectedItem().toString()));
-        return comboBox;
-    }
-
-    private JTextField createTextField(final String text) {
-        final JTextField textField = new JTextField(20);
-        textField.setName("Field");
-        textField.setText(text);
-        return textField;
-    }
-
-    private JButton createDisabledOkButton() {
-        final JButton button = new JButton("ok");
-        button.setName("OK");
-        button.setEnabled(false);
-        return button;
-    }
-
-    private JButton createCancelButton() {
-        final JButton button = new JButton("cancel");
-        button.setName("Cancel");
-        button.addActionListener(e -> this.dispose());
-        return button;
-    }
-
-    private static JLabel createLabel(final String text, final String name) {
-        JLabel label = new JLabel(text);
-        label.setName(name);
-        return label;
-    }
-
-}

core-java-modules/core-java-14/pom.xml

@@ -48,7 +48,6 @@
 
     <properties>
         <maven.compiler.release>14</maven.compiler.release>
-        <maven-compiler-plugin.version>3.8.1</maven-compiler-plugin.version>
         <surefire.plugin.version>3.0.0-M3</surefire.plugin.version>
     </properties>
 

core-java-modules/core-java-15/pom.xml

@@ -53,7 +53,6 @@
 
     <properties>
         <maven.compiler.release>15</maven.compiler.release>
-        <maven-compiler-plugin.version>3.8.1</maven-compiler-plugin.version>
         <surefire.plugin.version>3.0.0-M3</surefire.plugin.version>
     </properties>
 

core-java-modules/core-java-17/README.md

@@ -7,3 +7,4 @@
 - [Random Number Generators in Java 17](https://www.baeldung.com/java-17-random-number-generators)
 - [Sealed Classes and Interfaces in Java](https://www.baeldung.com/java-sealed-classes-interfaces)
 - [Migrate From Java 8 to Java 17](https://www.baeldung.com/java-migrate-8-to-17)
+- [Format Multiple ‘or’ Conditions in an If Statement in Java](https://www.baeldung.com/java-multiple-or-conditions-if-statement)

core-java-modules/core-java-17/src/test/java/com/baeldung/multipleorwithif/MultipleOrWithIfUnitTest.java

@@ -0,0 +1,126 @@
+package com.baeldung.multipleorwithif;
+
+import static java.time.Month.DECEMBER;
+import static java.time.Month.NOVEMBER;
+import static java.time.Month.OCTOBER;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.in;
+import static org.hamcrest.Matchers.is;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.time.Month;
+import java.util.List;
+import java.util.Random;
+import java.util.Set;
+import java.util.function.Predicate;
+
+import org.junit.jupiter.api.Test;
+
+class MultipleOrWithIfUnitTest {
+
+    private final Random rand = new Random();
+
+    final Set<Month> months = Set.of(OCTOBER, NOVEMBER, DECEMBER);
+
+    @Test
+    public void givenIfStatement_whenMultipleOrOperator_thenAssert() {
+        assertTrue(multipleOrOperatorIf(monthIn()));
+        assertFalse(multipleOrOperatorIf(monthNotIn()));
+    }
+
+    boolean multipleOrOperatorIf(Month month) {
+        if (month == OCTOBER || month == NOVEMBER || month == DECEMBER) {
+            return true;
+        }
+        return false;
+    }
+
+    @Test
+    public void givenSwitch_whenMultipleCase_thenBreakAndAssert() {
+        assertTrue(switchMonth(monthIn()));
+        assertFalse(switchMonth(monthNotIn()));
+    }
+
+    boolean switchMonth(Month month) {
+        return switch (month) {
+            case OCTOBER, NOVEMBER, DECEMBER -> true;
+            default -> false;
+        };
+    }
+
+    @Test
+    public void givenAllowedValuesList_whenContains_thenAssert() {
+        assertTrue(contains(monthIn()));
+        assertFalse(contains(monthNotIn()));
+    }
+
+    @Test
+    public void givenPredicates_whenTestMultipleOr_thenAssert() {
+        assertTrue(predicateWithIf(monthIn()));
+        assertFalse(predicateWithIf(monthNotIn()));
+    }
+
+    @Test
+    public void givenInputList_whenFilterWithPredicate_thenAssert() {
+
+        List<Month> list = List.of(monthIn(), monthIn(), monthNotIn());
+
+        list.stream()
+          .filter(this::predicateWithIf)
+          .forEach(m -> assertThat(m, is(in(months))));
+    }
+
+    Predicate<Month> orPredicate() {
+        Predicate<Month> predicate = x -> x == OCTOBER;
+        Predicate<Month> predicate1 = x -> x == NOVEMBER;
+        Predicate<Month> predicate2 = x -> x == DECEMBER;
+
+        return predicate.or(predicate1)
+          .or(predicate2);
+    }
+
+    boolean predicateWithIf(Month month) {
+        if (orPredicate().test(month)) {
+            return true;
+        }
+        return false;
+    }
+
+    @Test
+    public void givenContainsInSetPredicate_whenTestPredicate_thenAssert() {
+        Predicate<Month> collectionPredicate = this::contains;
+
+        assertTrue(collectionPredicate.test(monthIn()));
+        assertFalse(collectionPredicate.test(monthNotIn()));
+    }
+
+    @Test
+    public void givenInputList_whenFilterWithContains_thenAssert() {
+
+        List<Month> monthList = List.of(monthIn(), monthIn(), monthNotIn());
+
+        monthList.stream()
+          .filter(this::contains)
+          .forEach(m -> assertThat(m, is(in(months))));
+    }
+
+    private boolean contains(Month month) {
+        if (months.contains(month)) {
+            return true;
+        }
+        return false;
+    }
+
+    private Month monthIn() {
+        return Month.of(rand.ints(10, 13)
+          .findFirst()
+          .orElse(10));
+    }
+
+    private Month monthNotIn() {
+        return Month.of(rand.ints(1, 10)
+          .findFirst()
+          .orElse(1));
+    }
+}

core-java-modules/core-java-21/README.md

@@ -0,0 +1 @@
+## Relevant Articles

core-java-modules/core-java-21/pom.xml

@@ -0,0 +1,34 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>core-java-21</artifactId>
+    <name>core-java-21</name>
+
+    <parent>
+        <groupId>com.baeldung.core-java-modules</groupId>
+        <artifactId>core-java-modules</artifactId>
+        <version>0.0.1-SNAPSHOT</version>
+    </parent>
+
+<!--    <build>-->
+<!--        <plugins>-->
+<!--            <plugin>-->
+<!--                <groupId>org.apache.maven.plugins</groupId>-->
+<!--                <artifactId>maven-compiler-plugin</artifactId>-->
+<!--                <configuration>-->
+<!--                    <source>{maven.compiler.source.version}</source>-->
+<!--                    <target>{maven.compiler.target.version}</target>-->
+<!--                </configuration>-->
+<!--            </plugin>-->
+<!--        </plugins>-->
+<!--    </build>-->
+
+<!--    <properties>-->
+<!--        <maven.compiler.source.version>21</maven.compiler.source.version>-->
+<!--        <maven.compiler.target.version>21</maven.compiler.target.version>-->
+<!--        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>-->
+<!--    </properties>-->
+
+</project>

core-java-modules/core-java-21/src/main/java/com/baeldung/sequenced/collections/SequencedCollection.java

@@ -0,0 +1,15 @@
+package com.baeldung.sequenced.collections;
+
+/*
+interface SequencedCollection<E> extends Collection<E> {
+    // new method
+    SequencedCollection<E> reversed();
+    // methods promoted from Deque
+    void addFirst(E);
+    void addLast(E);
+    E getFirst();
+    E getLast();
+    E removeFirst();
+    E removeLast();
+}
+ */

core-java-modules/core-java-21/src/main/java/com/baeldung/sequenced/collections/SequencedMap.java

@@ -0,0 +1,18 @@
+package com.baeldung.sequenced.collections;
+
+/*
+interface SequencedMap<K,V> extends Map<K,V> {
+    // new methods
+    SequencedMap<K,V> reversed();
+    SequencedSet<K> sequencedKeySet();
+    SequencedCollection<V> sequencedValues();
+    SequencedSet<Entry<K,V>> sequencedEntrySet();
+    V putFirst(K, V);
+    V putLast(K, V);
+    // methods promoted from NavigableMap
+    Entry<K, V> firstEntry();
+    Entry<K, V> lastEntry();
+    Entry<K, V> pollFirstEntry();
+    Entry<K, V> pollLastEntry();
+}
+ */

core-java-modules/core-java-21/src/main/java/com/baeldung/sequenced/collections/SequencedSet.java

@@ -0,0 +1,7 @@
+package com.baeldung.sequenced.collections;
+
+/*
+interface SequencedSet<E> extends Set<E>, SequencedCollection<E> {
+    SequencedSet<E> reversed();    // covariant override
+}
+ */

core-java-modules/core-java-8-datetime-2/src/test/java/com/baeldung/stringtime/AddMinuteStringTimeUnitTest.java

@@ -0,0 +1,37 @@
+package com.baeldung.stringtime;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.time.LocalTime;
+import java.util.Calendar;
+import java.util.Date;
+import org.junit.jupiter.api.Test;
+
+public class AddMinuteStringTimeUnitTest {
+
+    @Test
+    public void givenTimeStringUsingSimpleDateFormat_whenIncrementedWith10Minutes_thenResultShouldBeCorrect() throws ParseException {
+        String timeString = "23:45";
+        SimpleDateFormat timeFormat = new SimpleDateFormat("HH:mm");
+        Date date = timeFormat.parse(timeString);
+
+        Calendar cal = Calendar.getInstance();
+        cal.setTime(date);
+        cal.add(Calendar.MINUTE, 10);
+        String result = timeFormat.format(cal.getTime());
+        assertEquals("23:55", result);
+
+    }
+
+    @Test
+    public void givenTimeStringUsingLocalTime_whenIncrementedWith10Minutes_thenResultShouldBeCorrect() {
+        String timeString = "23:45";
+        LocalTime time = LocalTime.parse(timeString);
+        LocalTime newTime = time.plusMinutes(10);
+        String result = newTime.toString();
+        assertEquals("23:55", result);
+    }
+
+}

core-java-modules/core-java-9-improvements/pom.xml

@@ -10,7 +10,7 @@
         <groupId>com.baeldung</groupId>
         <artifactId>parent-modules</artifactId>
         <version>1.0.0-SNAPSHOT</version>
-        <relativePath>../../</relativePath>
+        <relativePath>../../pom.xml</relativePath>
     </parent>
 
     <dependencies>

core-java-modules/core-java-9-jigsaw/library-core/pom.xml

@@ -4,9 +4,9 @@
     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>
     <parent>
-        <groupId>com.baeldung</groupId>
+        <groupId>com.baeldung.core-java-modules</groupId>
         <artifactId>core-java-9-jigsaw</artifactId>
-        <version>0.2-SNAPSHOT</version>
+        <version>0.0.1-SNAPSHOT</version>
     </parent>
 
     <artifactId>library-core</artifactId>

core-java-modules/core-java-9-jigsaw/pom.xml

@@ -11,10 +11,9 @@
     </modules>
 
     <parent>
-        <groupId>com.baeldung</groupId>
+        <groupId>com.baeldung.core-java-modules</groupId>
-        <artifactId>parent-modules</artifactId>
+        <artifactId>core-java-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
+        <version>0.0.1-SNAPSHOT</version>
-        <relativePath>../../</relativePath>
     </parent>
 
     <build>

core-java-modules/core-java-9-new-features/pom.xml

@@ -152,7 +152,6 @@
         <awaitility.version>4.0.2</awaitility.version>
         <maven.compiler.source>1.9</maven.compiler.source>
         <maven.compiler.target>1.9</maven.compiler.target>
-        <maven-jar-plugin.version>3.2.0</maven-jar-plugin.version>
     </properties>
 
 </project>

core-java-modules/core-java-9-streams/src/main/java/com/baeldung/streams/regexmatches/StreamFromRegexUtil.java

@@ -0,0 +1,16 @@
+package com.baeldung.streams.regexmatches;
+
+import java.util.regex.MatchResult;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import java.util.stream.Stream;
+
+public class StreamFromRegexUtil {
+
+    public static Stream<String> getStream(String input, String regex) {
+        Pattern pattern = Pattern.compile(regex);
+        Matcher matcher = pattern.matcher(input);
+        return matcher.results().map(MatchResult::group);
+    }
+
+}

core-java-modules/core-java-9-streams/src/test/java/com/baeldung/streams/regexmatches/StreamFromRegexUnitTest.java

@@ -0,0 +1,27 @@
+package com.baeldung.streams.regexmatches;
+
+import org.junit.Test;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+import static java.util.Arrays.asList;
+import static org.junit.Assert.assertEquals;
+
+public class StreamFromRegexUnitTest {
+
+    @Test
+    public void whenInputStringIncludeLettersAndNumbersAndRegex_ThenReturnStreamOfNumbers() {
+        List<String> result = StreamFromRegexUtil.getStream("There are 3 apples and 2 bananas on the table.", "\\d+")
+                .collect(Collectors.toList());
+        assertEquals(asList("3", "2"), result);
+    }
+
+    @Test
+    public void whenInputStringsAndRegex_ThenReturnStreamOfJavaWords() {
+        List<String> result = StreamFromRegexUtil.getStream("sample sentence with some words Java Java", "\\bJava\\b")
+                .collect(Collectors.toList());
+        assertEquals(asList("Java", "Java"), result);
+    }
+
+}

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

@@ -13,3 +13,5 @@ This module contains articles about advanced operations on arrays in Java. They
 - [Performance of System.arraycopy() vs. Arrays.copyOf()](https://www.baeldung.com/java-system-arraycopy-arrays-copyof-performance)
 - [Slicing Arrays in Java](https://www.baeldung.com/java-slicing-arrays)
 - [Combining Two or More Byte Arrays](https://www.baeldung.com/java-concatenate-byte-arrays)
+- [Calculating the Sum of Two Arrays in Java](https://www.baeldung.com/java-sum-arrays-element-wise)
+- [Find the Middle Element of an Array in Java](https://www.baeldung.com/java-array-middle-item)

core-java-modules/core-java-arrays-operations-advanced/src/main/java/com/baeldung/arraymiddle/MiddleOfArray.java

@@ -0,0 +1,65 @@
+package com.baeldung.arraymiddle;
+
+import java.util.Arrays;
+
+import org.apache.commons.lang3.ObjectUtils;
+
+public class MiddleOfArray {
+    int[] middleOfArray(int[] array) {
+        if (ObjectUtils.isEmpty(array) || array.length < 3)
+            return array;
+        int n = array.length;
+        int mid = n / 2;
+        if (n % 2 == 0) {
+            int mid2 = mid - 1;
+            return new int[] { array[mid2], array[mid] };
+        } else {
+            return new int[] { array[mid] };
+        }
+    }
+
+    int[] middleOfArrayWithStartEndNaive(int[] array, int start, int end) {
+        int mid = (start + end) / 2;
+        int n = end - start;
+        if (n % 2 == 0) {
+            int mid2 = mid - 1;
+            return new int[] { array[mid2], array[mid] };
+        } else {
+            return new int[] { array[mid] };
+        }
+    }
+
+    int[] middleOfArrayWithStartEnd(int[] array, int start, int end) {
+        int mid = start + (end - start) / 2;
+        int n = end - start;
+        if (n % 2 == 0) {
+            int mid2 = mid - 1;
+            return new int[] { array[mid2], array[mid] };
+        } else {
+            return new int[] { array[mid] };
+        }
+    }
+
+    int[] middleOfArrayWithStartEndBitwise(int[] array, int start, int end) {
+        int mid = (start + end) >>> 1;
+        int n = end - start;
+        if (n % 2 == 0) {
+            int mid2 = mid - 1;
+            return new int[] { array[mid2], array[mid] };
+        } else {
+            return new int[] { array[mid] };
+        }
+    }
+
+    int medianOfArray(int[] array, int start, int end) {
+        Arrays.sort(array); // for safety. This can be ignored
+        int mid = (start + end) >>> 1;
+        int n = end - start;
+        if (n % 2 == 0) {
+            int mid2 = mid - 1;
+            return (array[mid2] + array[mid]) / 2;
+        } else {
+            return array[mid];
+        }
+    }
+}

core-java-modules/core-java-arrays-operations-advanced/src/test/java/com/baeldung/arraymiddle/MiddleOfArrayUnitTest.java

@@ -0,0 +1,89 @@
+package com.baeldung.arraymiddle;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class MiddleOfArrayUnitTest {
+
+    @Test
+    public void givenArrayOfEvenLength_whenMiddleOfArray_thenReturn2Values() {
+        int[] array = new int[100];
+        for (int i = 0; i < array.length; i++) {
+            array[i] = i + 1;
+        }
+        int[] expectedMidArray = { 50, 51 };
+        MiddleOfArray middleOfArray = new MiddleOfArray();
+        Assert.assertArrayEquals(expectedMidArray, middleOfArray.middleOfArray(array));
+    }
+
+    @Test
+    public void givenArrayOfEdgeCaseLength_whenMiddleOfArray_thenReturn2Values() {
+        int[] array = new int[0];
+        int[] expectedMidArray = new int[0];
+        MiddleOfArray middleOfArray = new MiddleOfArray();
+        Assert.assertArrayEquals(expectedMidArray, middleOfArray.middleOfArray(array));
+
+        array = new int[] { 1, 2 };
+        expectedMidArray = new int[] { 1, 2 };
+
+        Assert.assertArrayEquals(expectedMidArray, middleOfArray.middleOfArray(array));
+    }
+
+    @Test
+    public void givenArrayOfOddLength_whenMiddleOfArray_thenReturnMid() {
+        int[] array = new int[99];
+        for (int i = 0; i < array.length; i++) {
+            array[i] = i + 1;
+        }
+        int[] expectedMidArray = { 50 };
+        MiddleOfArray middleOfArray = new MiddleOfArray();
+        Assert.assertArrayEquals(expectedMidArray, middleOfArray.middleOfArray(array));
+    }
+
+    @Test
+    public void givenArrayWithStartAndEnd_whenMiddleOfArray_thenReturnMid() {
+        int[] array = new int[100];
+        for (int i = 0; i < array.length; i++) {
+            array[i] = i + 1;
+        }
+        int[] expectedMidArray = { 58 };
+        MiddleOfArray middleOfArray = new MiddleOfArray();
+        Assert.assertArrayEquals(expectedMidArray, middleOfArray.middleOfArrayWithStartEndNaive(array, 55, 60));
+
+        expectedMidArray = new int[] { 58, 59 };
+        Assert.assertArrayEquals(expectedMidArray, middleOfArray.middleOfArrayWithStartEndNaive(array, 56, 60));
+    }
+
+    @Test
+    public void givenArrayWithStartAndEndOptimized_whenMiddleOfArray_thenReturnMid() {
+        int[] array = new int[100];
+        for (int i = 0; i < array.length; i++) {
+            array[i] = i + 1;
+        }
+        int[] expectedMidArray = { 78 };
+        MiddleOfArray middleOfArray = new MiddleOfArray();
+        Assert.assertArrayEquals(expectedMidArray, middleOfArray.middleOfArrayWithStartEnd(array, 55, 100));
+    }
+
+    @Test
+    public void givenArrayWithStartAndEndBitwise_whenMiddleOfArray_thenReturnMid() {
+        int[] array = new int[100];
+        for (int i = 0; i < array.length; i++) {
+            array[i] = i + 1;
+        }
+        int[] expectedMidArray = { 78 };
+        MiddleOfArray middleOfArray = new MiddleOfArray();
+        Assert.assertArrayEquals(expectedMidArray, middleOfArray.middleOfArrayWithStartEndBitwise(array, 55, 100));
+    }
+
+    @Test
+    public void givenArrayWithStartAndEnd_whenMedianOfArray_thenReturnMid() {
+        int[] array = new int[100];
+        for (int i = 0; i < array.length; i++) {
+            array[i] = i + 1;
+        }
+        int expectMedian = 50;
+        MiddleOfArray middleOfArray = new MiddleOfArray();
+        Assert.assertEquals(expectMedian, middleOfArray.medianOfArray(array, 0, 100));
+    }
+}

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

@@ -13,4 +13,5 @@ This module contains articles about conversions among Collection types and array
 - [Combining Two Lists Into a Map in Java](https://www.baeldung.com/java-combine-two-lists-into-map)
 - [Convert a List of Strings to a List of Integers](https://www.baeldung.com/java-convert-list-strings-to-integers)
 - [Convert List to Long[] Array in Java](https://www.baeldung.com/java-convert-list-object-to-long-array)
+- [Get the First n Elements of a List Into an Array](https://www.baeldung.com/java-take-start-elements-list-array)
 - More articles: [[<-- prev]](../core-java-collections-conversions)

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

@@ -12,3 +12,4 @@ This module contains articles about the Java List collection
 - [Get Unique Values From an ArrayList in Java](https://www.baeldung.com/java-unique-values-arraylist)
 - [Converting a Java List to a Json Array](https://www.baeldung.com/java-converting-list-to-json-array)
 - [What’s the Difference Between Iterator and ListIterator?](https://www.baeldung.com/java-iterator-vs-listiterator)
+- [Create List of Object From Another Type Using Java 8](https://www.baeldung.com/java-generate-list-different-type)

core-java-modules/core-java-collections-list-5/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"
+    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">
+    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>core-java-collections-list-5</artifactId>
     <name>core-java-collections-list-5</name>

core-java-modules/core-java-collections-list-5/src/test/java/com/baeldung/java/streamtoanotherlist/CreateListOfDifferentTypeUsingStreamUnitTest.java

@@ -0,0 +1,114 @@
+package com.baeldung.java.streamtoanotherlist;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Objects;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+import org.assertj.core.util.Lists;
+import org.junit.jupiter.api.Test;
+
+import lombok.Getter;
+
+@Getter
+class Employee {
+    private final String name;
+    private final Set<String> hobbies = new HashSet<>();
+    private final String email;
+    private String department;
+
+    public Employee(String name, String email, Collection<String> hobbies) {
+        this.name = name;
+        this.email = email;
+        this.hobbies.addAll(hobbies);
+    }
+}
+
+class TennisPlayerCandidate {
+    private final String name;
+    private final String email;
+    private final Boolean confirmed = Boolean.FALSE;
+
+    public TennisPlayerCandidate(String name, String email) {
+        this.name = name;
+        this.email = email;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o)
+            return true;
+        if (!(o instanceof TennisPlayerCandidate))
+            return false;
+
+        TennisPlayerCandidate that = (TennisPlayerCandidate) o;
+
+        if (!Objects.equals(name, that.name))
+            return false;
+        return Objects.equals(email, that.email);
+    }
+
+    @Override
+    public int hashCode() {
+        int result = name != null ? name.hashCode() : 0;
+        result = 31 * result + (email != null ? email.hashCode() : 0);
+        return result;
+    }
+}
+
+public class CreateListOfDifferentTypeUsingStreamUnitTest {
+    private final static List<Employee> EMPLOYEES = Lists.newArrayList(
+      // @formatter:off
+      new Employee("Kai", "kai@company.com", Lists.newArrayList("Football", "Reading", "Chess")),
+      new Employee("Eric", "eric@company.com", Lists.newArrayList("Tennis", "Baseball", "Singing")),
+      new Employee("Saajan", "saajan@company.com", Lists.newArrayList("Tennis", "Baseball", "Singing")),
+      new Employee("Kevin", "kevin@company.com", Lists.newArrayList("Dancing", "Computer Games", "Tennis")),
+      new Employee("Amanda", "amanda@company.com", Lists.newArrayList("Painting", "Yoga", "Dancing"))
+      //@formatter:on
+    );
+
+    private final static List<TennisPlayerCandidate> EXPECTED = Lists.newArrayList(
+      // @formatter:off
+      new TennisPlayerCandidate("Eric", "eric@company.com"),
+      new TennisPlayerCandidate("Saajan", "saajan@company.com"),
+      new TennisPlayerCandidate("Kevin", "kevin@company.com")
+      //@formatter:on
+    );
+
+    @Test
+    void whenUsingStreamForEachFillingAnotherList_thenGetExpectedResult() {
+        List<TennisPlayerCandidate> result = new ArrayList<>();
+        EMPLOYEES.forEach(e -> {
+            if (e.getHobbies()
+              .contains("Tennis")) {
+                result.add(new TennisPlayerCandidate(e.getName(), e.getEmail()));
+            }
+        });
+
+        assertEquals(EXPECTED, result);
+    }
+
+    @Test
+    void whenUsingStreamMap_thenGetExpectedResult() {
+        List<TennisPlayerCandidate> result = EMPLOYEES.stream()
+          .filter(e -> e.getHobbies()
+            .contains("Tennis"))
+          .map(e -> new TennisPlayerCandidate(e.getName(), e.getEmail()))
+          .collect(Collectors.toList());
+        assertEquals(EXPECTED, result);
+    }
+
+    @Test
+    void whenUsingCollectorMapping_thenGetExpectedResult() {
+        List<TennisPlayerCandidate> result = EMPLOYEES.stream()
+          .filter(e -> e.getHobbies()
+            .contains("Tennis"))
+          .collect(Collectors.mapping(e -> new TennisPlayerCandidate(e.getName(), e.getEmail()), Collectors.toList()));
+        assertEquals(EXPECTED, result);
+    }
+}

core-java-modules/core-java-collections-maps-3/README.md

@@ -9,4 +9,5 @@ This module contains articles about Map data structures in Java.
 - [Collections.synchronizedMap vs. ConcurrentHashMap](https://www.baeldung.com/java-synchronizedmap-vs-concurrenthashmap)
 - [Java HashMap Load Factor](https://www.baeldung.com/java-hashmap-load-factor)
 - [Converting Java Properties to HashMap](https://www.baeldung.com/java-convert-properties-to-hashmap)
+- [Get Values and Keys as ArrayList From a HashMap](https://www.baeldung.com/java-values-keys-arraylists-hashmap)
 - More articles: [[<-- prev]](/core-java-modules/core-java-collections-maps-2)

core-java-modules/core-java-collections-maps/src/main/java/com/baeldung/map/MapClear.java

@@ -0,0 +1,49 @@
+package com.baeldung.map;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class MapClear {
+    public static Map returnCopyAndClearMap() {
+        // Create a HashMap
+        Map<String, Integer> scores = new HashMap<>();
+        Map<String, Integer> scores_copy;
+
+        // Add some key-value pairs
+        scores.put("Alice", 90);
+        scores.put("Bob", 85);
+        scores.put("Charlie", 95);
+
+        scores_copy = scores;
+
+        System.out.println("Before clearing: " + scores);
+
+        // Clear the map
+        scores.clear();
+
+        System.out.println("After clearing: " + scores);
+        return scores_copy;
+    }
+
+    public static Map returnCopyAndRewriteMap() {
+        // Create a HashMap
+        Map<String, Integer> scores = new HashMap<>();
+        Map<String, Integer> scores_copy;
+
+        // Add some key-value pairs
+        scores.put("Alice", 90);
+        scores.put("Bob", 85);
+        scores.put("Charlie", 95);
+
+        scores_copy = scores;
+
+        System.out.println("Before clearing: " + scores);
+
+        // Create a new map
+        scores = new HashMap<>();
+
+        System.out.println("After clearing: " + scores);
+
+        return scores_copy;
+    }
+}

core-java-modules/core-java-collections-maps/src/test/java/com/baeldung/map/MapClearUnitTest.java

@@ -0,0 +1,20 @@
+package com.baeldung.map;
+
+import java.util.Map;
+
+import org.junit.Test;
+
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class MapClearUnitTest {
+    @Test
+    public void givenMap_returnEntryAndClearContent() {
+        Map entry = MapClear.returnCopyAndClearMap();
+        assertTrue(entry.isEmpty());
+    }
+
+    @Test public void givenMap_returnEntryAndRewriteContent() {
+        Map entry = MapClear.returnCopyAndRewriteMap();
+        assertTrue(!entry.isEmpty());
+    }
+}

core-java-modules/core-java-collections-maps/src/test/java/com/baeldung/map/UsingtoStringUnitTest.java

@@ -0,0 +1,42 @@
+package com.baeldung.map;
+
+import org.junit.Test;
+
+import java.util.HashMap;
+
+import static org.junit.Assert.assertEquals;
+
+public class UsingtoStringUnitTest {
+
+    @Test
+    public void given_HashMapString_whenUsingtoString_thenConvertToHashMapObject() {
+        // Example string representation of a HashMap
+        String hashMapString = "{key1=value1, key2=value2, key3=value3}";
+
+        // Remove unnecessary characters
+        String keyValuePairs = hashMapString.replaceAll("[{}\\s]", "");
+
+        // Split into individual key-value pairs
+        String[] pairs = keyValuePairs.split(",");
+
+        // Create a new HashMap
+        HashMap<String, String> expectedHashMap = new HashMap<>();
+        expectedHashMap.put("key1", "value1");
+        expectedHashMap.put("key2", "value2");
+        expectedHashMap.put("key3", "value3");
+
+        HashMap<String, String> actualHashMap = new HashMap<>();
+
+        // Parse and populate the HashMap
+        for (String pair : pairs) {
+            String[] keyValue = pair.split("=");
+            if (keyValue.length == 2) {
+                actualHashMap.put(keyValue[0], keyValue[1]);
+            }
+        }
+
+        // Assert that the converted HashMap matches the expected one
+        assertEquals(expectedHashMap, actualHashMap);
+    }
+
+}

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

@@ -4,4 +4,5 @@
 - [A Guide to LinkedHashSet in Java](https://www.baeldung.com/java-linkedhashset)
 - [Sorting a HashSet in Java](https://www.baeldung.com/java-sort-hashset)
 - [How to Get First Item From a Java Set](https://www.baeldung.com/first-item-set)
+- [Cartesian Product of Any Number of Sets in Java](https://www.baeldung.com/java-cartesian-product-sets)
 - More articles: [[<-- prev]](/core-java-modules/core-java-collections-set)

core-java-modules/core-java-collections-set-2/pom.xml

@@ -20,6 +20,23 @@
             <version>${junit-platform.version}</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-collections4</artifactId>
+            <version>4.4</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.testng</groupId>
+            <artifactId>testng</artifactId>
+            <version>7.7.0</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.google.guava</groupId>
+            <artifactId>guava</artifactId>
+            <version>32.1.1-jre</version>
+        </dependency>
     </dependencies>
 
     <build>

core-java-modules/core-java-collections-set-2/src/main/java/com/baeldung/cartesianproduct/CartesianProduct.java

@@ -0,0 +1,75 @@
+package com.baeldung.cartesianproduct;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import com.google.common.collect.Sets;
+
+public class CartesianProduct {
+    public List<List<Object>> getCartesianProductIterative(List<List<Object>> sets) {
+        List<List<Object>> result = new ArrayList<>();
+        if(sets == null || sets.isEmpty()) {
+            return result;
+        }
+        int totalSets = sets.size();
+        int totalCombinations = 1 << totalSets;
+        for(int i = 0; i < totalCombinations; i++) {
+            List<Object> combination = new ArrayList<>();
+            for(int j = 0; j < totalSets; j++) {
+                if (((i >> j) & 1) == 1) {
+                    combination.add(sets.get(j).get(0));
+                } else {
+                    combination.add(sets.get(j).get(1));
+                }
+            }
+            result.add(combination);
+        }
+        return result;
+    }
+
+    public List<List<Object>> getCartesianProductRecursive(List<List<Object>> sets) {
+        List<List<Object>> result = new ArrayList<>();
+        getCartesianProductRecursiveHelper(sets, 0, new ArrayList<>(), result);
+        return result;
+    }
+
+    private void getCartesianProductRecursiveHelper(List<List<Object>> sets, int index, List<Object> current, List<List<Object>> result) {
+        if(index == sets.size()) {
+            result.add(new ArrayList<>(current));
+            return;
+        }
+        List<Object> currentSet = sets.get(index);
+        for(Object element: currentSet) {
+            current.add(element);
+            getCartesianProductRecursiveHelper(sets, index+1, current, result);
+            current.remove(current.size() - 1);
+        }
+    }
+
+    public List<List<Object>> getCartesianProductUsingStreams(List<List<Object>> sets) {
+        return cartesianProduct(sets,0).collect(Collectors.toList());
+    }
+
+    public Stream<List<Object>> cartesianProduct(List<List<Object>> sets, int index) {
+        if(index == sets.size()) {
+            List<Object> emptyList = new ArrayList<>();
+            return Stream.of(emptyList);
+        }
+        List<Object> currentSet = sets.get(index);
+        return currentSet.stream().flatMap(element -> cartesianProduct(sets, index+1)
+            .map(list -> {
+                List<Object> newList = new ArrayList<>(list);
+                newList.add(0, element); return newList;
+            }));
+    }
+
+    public List<List<Object>> getCartesianProductUsingGuava(List<Set<Object>> sets) {
+        Set<List<Object>> cartesianProduct = Sets.cartesianProduct(sets);
+        List<List<Object>> cartesianList = new ArrayList<>(cartesianProduct);
+        return cartesianList;
+    }
+
+}

core-java-modules/core-java-collections-set-2/src/main/java/com/baeldung/indexawareset/IndexOfElementsInSet.java

@@ -0,0 +1,29 @@
+package com.baeldung.indexawareset;
+
+import java.util.Iterator;
+import java.util.Set;
+
+public class IndexOfElementsInSet<E> {
+    public int getIndexUsingIterator(Set<E> set, E element) {
+        Iterator<E> iterator = set.iterator();
+        int index = 0;
+        while (iterator.hasNext()) {
+            if (element.equals(iterator.next())) {
+                return index;
+            }
+            index++;
+        }
+        return -1;
+    }
+
+    public int getIndexUsingForEach(Set<E> set, E element) {
+        int index = 0;
+        for (E current : set) {
+            if (element.equals(current)) {
+                return index;
+            }
+            index++;
+        }
+        return -1;
+    }
+}

core-java-modules/core-java-collections-set-2/src/main/java/com/baeldung/indexawareset/InsertionIndexAwareSet.java

@@ -0,0 +1,20 @@
+package com.baeldung.indexawareset;
+
+import java.util.LinkedHashSet;
+
+public class InsertionIndexAwareSet<E> extends LinkedHashSet<E> {
+    public InsertionIndexAwareSet() {
+        super();
+    }
+
+    public int getIndexOf(E element) {
+        int index = 0;
+        for (E current : this) {
+            if (current.equals(element)) {
+                return index;
+            }
+            index++;
+        }
+        return -1;
+    }
+}

core-java-modules/core-java-collections-set-2/src/test/java/com/baeldung/cartesianproduct/CartesianProductUnitTest.java

@@ -0,0 +1,93 @@
+package com.baeldung.cartesianproduct;
+
+import static org.testng.Assert.assertEquals;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+import org.testng.annotations.Test;
+
+public class CartesianProductUnitTest {
+    private CartesianProduct cp = new CartesianProduct();
+    List<List<Object>> sets = Arrays.asList(
+        Arrays.asList(10, 20),
+        Arrays.asList("John", "Jack"),
+        Arrays.asList('I', 'J')
+    );
+
+    @Test
+    public void whenUsingStreams_thenCalculateCartesianProduct() {
+        List<List<Object>> expected = Arrays.asList(
+            Arrays.asList(10, "John", 'I'),
+            Arrays.asList(10, "John", 'J'),
+            Arrays.asList(10, "Jack", 'I'),
+            Arrays.asList(10, "Jack", 'J'),
+            Arrays.asList(20, "John", 'I'),
+            Arrays.asList(20, "John", 'J'),
+            Arrays.asList(20, "Jack", 'I'),
+            Arrays.asList(20, "Jack", 'J')
+        );
+        List<List<Object>> cartesianProduct = cp.getCartesianProductUsingStreams(sets);
+
+        assertEquals(expected, cartesianProduct);
+    }
+
+    @Test
+    public void whenUsingRecursion_thenCalculateCartesianProduct() {
+        List<List<Object>> expected = Arrays.asList(
+            Arrays.asList(10, "John", 'I'),
+            Arrays.asList(10, "John", 'J'),
+            Arrays.asList(10, "Jack", 'I'),
+            Arrays.asList(10, "Jack", 'J'),
+            Arrays.asList(20, "John", 'I'),
+            Arrays.asList(20, "John", 'J'),
+            Arrays.asList(20, "Jack", 'I'),
+            Arrays.asList(20, "Jack", 'J')
+        );
+        List<List<Object>> cartesianProduct = cp.getCartesianProductRecursive(sets);
+
+        assertEquals(expected, cartesianProduct);
+    }
+
+    @Test
+    public void whenUsingIterativeApproach_thenCalculateCartesianProduct() {
+        List<List<Object>> expected = Arrays.asList(
+            Arrays.asList(20, "Jack", 'J'),
+            Arrays.asList(10, "Jack", 'J'),
+            Arrays.asList(20, "John", 'J'),
+            Arrays.asList(10, "John", 'J'),
+            Arrays.asList(20, "Jack", 'I'),
+            Arrays.asList(10, "Jack", 'I'),
+            Arrays.asList(20, "John", 'I'),
+            Arrays.asList(10, "John", 'I')
+        );
+        List<List<Object>> cartesianProduct = cp.getCartesianProductIterative(sets);
+
+        assertEquals(expected, cartesianProduct);
+    }
+
+    @Test
+    public void whenUsingGuava_thenCalculateCartesianProduct() {
+        List<Set<Object>> sets = new ArrayList<>();
+        sets.add(new HashSet<>(Arrays.asList(10, 20)));
+        sets.add(new HashSet<>(Arrays.asList("John", "Jack")));
+        sets.add(new HashSet<>(Arrays.asList('I', 'J')));
+
+        List<List<Object>> expected = Arrays.asList(
+            Arrays.asList(20, "John", 'I'),
+            Arrays.asList(20, "John", 'J'),
+            Arrays.asList(20, "Jack", 'I'),
+            Arrays.asList(20, "Jack", 'J'),
+            Arrays.asList(10, "John", 'I'),
+            Arrays.asList(10, "John", 'J'),
+            Arrays.asList(10, "Jack", 'I'),
+            Arrays.asList(10, "Jack", 'J')
+        );
+        List<List<Object>> cartesianProduct = cp.getCartesianProductUsingGuava(sets);
+
+        assertEquals(expected, cartesianProduct);
+    }
+}

core-java-modules/core-java-collections-set-2/src/test/java/com/baeldung/indexawareset/IndexOfSetElementsUsingListUnitTest.java

@@ -0,0 +1,108 @@
+package com.baeldung.indexawareset;
+
+import java.util.HashSet;
+import java.util.LinkedHashSet;
+import java.util.Set;
+import java.util.TreeSet;
+
+import org.apache.commons.collections4.set.ListOrderedSet;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class IndexOfSetElementsUsingListUnitTest {
+    @Test
+    public void givenHashSet_whenIndexOfElement_thenGivesIndex() {
+        Set<Integer> set = new HashSet<>();
+        set.add(100);
+        set.add(20);
+        set.add(300);
+        set.add(0);
+        set.add(-1);
+        set.add(300);
+
+        IndexOfElementsInSet<Integer> integerIndexOfElementsInSet = new IndexOfElementsInSet<>();
+        int index100 = integerIndexOfElementsInSet.getIndexUsingIterator(set, 100);
+        Assert.assertEquals(index100, integerIndexOfElementsInSet.getIndexUsingIterator(set, 100));
+
+        Assert.assertEquals(-1, integerIndexOfElementsInSet.getIndexUsingIterator(set, 12));
+    }
+
+    @Test
+    public void givenLinkedHashSet_whenIndexOfElement_thenGivesIndex() {
+        Set<Integer> set = new LinkedHashSet<>();
+        set.add(100);
+        set.add(20);
+        set.add(300);
+        set.add(0);
+        set.add(-1);
+        set.add(300);
+
+        IndexOfElementsInSet<Integer> integerIndexOfElementsInSet = new IndexOfElementsInSet<>();
+        Assert.assertEquals(0, integerIndexOfElementsInSet.getIndexUsingIterator(set, 100));
+    }
+
+    @Test
+    public void givenTreeSet_whenIndexOfElement_thenGivesIndex() {
+        Set<Integer> set = new TreeSet<>();
+        set.add(100);
+        set.add(20);
+        set.add(300);
+        set.add(0);
+        set.add(-1);
+        set.add(300);
+
+        IndexOfElementsInSet<Integer> integerIndexOfElementsInSet = new IndexOfElementsInSet<>();
+        Assert.assertEquals(0, integerIndexOfElementsInSet.getIndexUsingIterator(set, -1));
+        Assert.assertEquals(3, integerIndexOfElementsInSet.getIndexUsingIterator(set, 100));
+    }
+
+    @Test
+    public void givenIndexAwareSet_whenIndexOfElement_thenGivesIndex() {
+        InsertionIndexAwareSet<Integer> set = new InsertionIndexAwareSet<>();
+        set.add(100);
+        set.add(20);
+        set.add(300);
+        Assert.assertEquals(0, set.getIndexOf(100));
+        Assert.assertEquals(2, set.getIndexOf(300));
+        Assert.assertEquals(-1, set.getIndexOf(0));
+    }
+
+    @Test
+    public void givenIndexAwareSetWithStrings_whenIndexOfElement_thenGivesIndex() {
+        InsertionIndexAwareSet<String> set = new InsertionIndexAwareSet<>();
+        set.add("Go");
+        set.add("Java");
+        set.add("Scala");
+        set.add("Python");
+        Assert.assertEquals(0, set.getIndexOf("Go"));
+        Assert.assertEquals(2, set.getIndexOf("Scala"));
+        Assert.assertEquals(-1, set.getIndexOf("C++"));
+    }
+
+    @Test
+    public void givenListOrderedSet_whenIndexOfElement_thenGivesIndex() {
+        ListOrderedSet<Integer> set = new ListOrderedSet<>();
+        set.add(12);
+        set.add(0);
+        set.add(-1);
+        set.add(50);
+
+        Assert.assertEquals(0, set.indexOf(12));
+        Assert.assertEquals(2, set.indexOf(-1));
+        Assert.assertEquals(-1, set.indexOf(100));
+    }
+
+    @Test
+    public void givenLinkedHashSet_whenIndexUsingUtilityMethod_thenReturnsIndex() {
+        Set<Integer> set = new LinkedHashSet<>();
+        set.add(100);
+        set.add(20);
+        set.add(300);
+        set.add(0);
+        set.add(-1);
+        set.add(300);
+
+        IndexOfElementsInSet<Integer> integerIndexOfElementsInSet = new IndexOfElementsInSet<>();
+        Assert.assertEquals(-1, integerIndexOfElementsInSet.getIndexUsingForEach(set, 150));
+    }
+}

core-java-modules/core-java-concurrency-advanced-4/src/main/java/com/baeldung/producerconsumer/Consumer.java

@@ -4,6 +4,7 @@ import java.util.logging.Logger;
 
 public class Consumer implements Runnable {
     private static final Logger log = Logger.getLogger(Consumer.class.getCanonicalName());
+    private boolean running = false;
     private final DataQueue dataQueue;
 
     public Consumer(DataQueue dataQueue) {
@@ -12,26 +13,36 @@ public class Consumer implements Runnable {
 
     @Override
     public void run() {
+        running = true;
         consume();
     }
 
+    public void stop() {
+        running = false;
+    }
+
     public void consume() {
-        while (dataQueue.runFlag) {
+        while (running) {
-            while (dataQueue.isEmpty() && dataQueue.runFlag) {
+
+            if (dataQueue.isEmpty()) {
                 try {
-                    dataQueue.waitOnEmpty();
+                    dataQueue.waitIsNotEmpty();
                 } catch (InterruptedException e) {
-                    e.printStackTrace();
+                    log.severe("Error while waiting to Consume messages.");
                     break;
                 }
             }
-            if (!dataQueue.runFlag) {
+
+            // avoid spurious wake-up
+            if (!running) {
                 break;
             }
-            Message message = dataQueue.remove();
+
-            dataQueue.notifyAllForFull();
+            Message message = dataQueue.poll();
             useMessage(message);
 
+            //Sleeping on random time to make it realistic
+            ThreadUtil.sleep((long) (Math.random() * 100));
         }
         log.info("Consumer Stopped");
     }
@@ -40,14 +51,7 @@ public class Consumer implements Runnable {
         if (message != null) {
             log.info(String.format("[%s] Consuming Message. Id: %d, Data: %f%n",
                     Thread.currentThread().getName(), message.getId(), message.getData()));
-
-            //Sleeping on random time to make it realistic
-            ThreadUtil.sleep((long) (message.getData() * 100));
         }
     }
 
-    public void stop() {
-        dataQueue.runFlag = false;
-        dataQueue.notifyAllForEmpty();
-    }
 }

core-java-modules/core-java-concurrency-advanced-4/src/main/java/com/baeldung/producerconsumer/DataQueue.java

@@ -6,10 +6,8 @@ import java.util.Queue;
 public class DataQueue {
     private final Queue<Message> queue = new LinkedList<>();
     private final int maxSize;
-    private final Object FULL_QUEUE = new Object();
+    private final Object IS_NOT_FULL = new Object();
-    private final Object EMPTY_QUEUE = new Object();
+    private final Object IS_NOT_EMPTY = new Object();
-
-    public boolean runFlag = true;
 
     DataQueue(int maxSize) {
         this.maxSize = maxSize;
@@ -23,39 +21,42 @@ public class DataQueue {
         return queue.isEmpty();
     }
 
-    public void waitOnFull() throws InterruptedException {
+    public void waitIsNotFull() throws InterruptedException {
-        synchronized (FULL_QUEUE) {
+        synchronized (IS_NOT_FULL) {
-            FULL_QUEUE.wait();
+            IS_NOT_FULL.wait();
         }
     }
 
-    public void waitOnEmpty() throws InterruptedException {
+    public void waitIsNotEmpty() throws InterruptedException {
-        synchronized (EMPTY_QUEUE) {
+        synchronized (IS_NOT_EMPTY) {
-            EMPTY_QUEUE.wait();
+            IS_NOT_EMPTY.wait();
-        }
-    }
-
-    public void notifyAllForFull() {
-        synchronized (FULL_QUEUE) {
-            FULL_QUEUE.notifyAll();
-        }
-    }
-
-    public void notifyAllForEmpty() {
-        synchronized (EMPTY_QUEUE) {
-            EMPTY_QUEUE.notifyAll();
         }
     }
 
     public void add(Message message) {
-        synchronized (queue) {
+        queue.add(message);
-            queue.add(message);
+        notifyIsNotEmpty();
+    }
+
+    public Message poll() {
+        Message mess = queue.poll();
+        notifyIsNotFull();
+        return mess;
+    }
+
+    public Integer getSize() {
+        return queue.size();
+    }
+
+    private void notifyIsNotFull() {
+        synchronized (IS_NOT_FULL) {
+            IS_NOT_FULL.notify();
         }
     }
 
-    public Message remove() {
+    private void notifyIsNotEmpty() {
-        synchronized (queue) {
+        synchronized (IS_NOT_EMPTY) {
-            return queue.poll();
+            IS_NOT_EMPTY.notify();
         }
     }
 }

core-java-modules/core-java-concurrency-advanced-4/src/main/java/com/baeldung/producerconsumer/Producer.java

@@ -1,60 +1,63 @@
 package com.baeldung.producerconsumer;
 
+import java.util.concurrent.atomic.AtomicInteger;
 import java.util.logging.Logger;
 
 public class Producer implements Runnable {
     private static final Logger log = Logger.getLogger(Producer.class.getCanonicalName());
+    private static final AtomicInteger idSequence = new AtomicInteger(0);
+    private boolean running = false;
     private final DataQueue dataQueue;
 
-    private static int idSequence = 0;
-
     public Producer(DataQueue dataQueue) {
         this.dataQueue = dataQueue;
     }
 
     @Override
     public void run() {
+        running = true;
         produce();
     }
 
+    public void stop() {
+        running = false;
+    }
+
     public void produce() {
-        while (dataQueue.runFlag) {
+
-            while (dataQueue.isFull() && dataQueue.runFlag) {
+        while (running) {
+
+            if (dataQueue.isFull()) {
                 try {
-                    dataQueue.waitOnFull();
+                    dataQueue.waitIsNotFull();
                 } catch (InterruptedException e) {
-                    e.printStackTrace();
+                    log.severe("Error while waiting to Produce messages.");
                     break;
                 }
             }
-            if (!dataQueue.runFlag) {
+
+            // avoid spurious wake-up
+            if (!running) {
                 break;
             }
-            Message message = generateMessage();
-            dataQueue.add(message);
-            dataQueue.notifyAllForEmpty();
 
+            dataQueue.add(generateMessage());
+
+            log.info("Size of the queue is: " + dataQueue.getSize());
+
+            //Sleeping on random time to make it realistic
+            ThreadUtil.sleep((long) (Math.random() * 100));
         }
+
         log.info("Producer Stopped");
     }
 
     private Message generateMessage() {
-        Message message = new Message(incrementAndGetId(), Math.random());
+        Message message = new Message(idSequence.incrementAndGet(), Math.random());
         log.info(String.format("[%s] Generated Message. Id: %d, Data: %f%n",
                 Thread.currentThread().getName(), message.getId(), message.getData()));
 
-        //Sleeping on random time to make it realistic
-        ThreadUtil.sleep((long) (message.getData() * 100));
-
         return message;
     }
 
-    private static int incrementAndGetId() {
-        return ++idSequence;
-    }
-
-    public void stop() {
-        dataQueue.runFlag = false;
-        dataQueue.notifyAllForFull();
-    }
 }

core-java-modules/core-java-concurrency-advanced-4/src/main/java/com/baeldung/producerconsumer/ProducerConsumerDemonstrator.java

@@ -27,7 +27,7 @@ public class ProducerConsumerDemonstrator {
         // let threads run for two seconds
         sleep(2000);
 
-        // Stop threads
+        // stop threads
         producer.stop();
         consumer.stop();
 
@@ -36,28 +36,34 @@ public class ProducerConsumerDemonstrator {
 
     public static void demoMultipleProducersAndMultipleConsumers() {
         DataQueue dataQueue = new DataQueue(MAX_QUEUE_CAPACITY);
-        int producerCount = 3;
+        int producerCount = 5;
-        int consumerCount = 3;
+        int consumerCount = 5;
         List<Thread> threads = new ArrayList<>();
-        Producer producer = new Producer(dataQueue);
+        List<Producer> producers = new ArrayList<>();
+        List<Consumer> consumers = new ArrayList<>();
+
         for(int i = 0; i < producerCount; i++) {
+            Producer producer = new Producer(dataQueue);
             Thread producerThread = new Thread(producer);
             producerThread.start();
             threads.add(producerThread);
+            producers.add(producer);
         }
-        Consumer consumer = new Consumer(dataQueue);
+
         for(int i = 0; i < consumerCount; i++) {
+            Consumer consumer = new Consumer(dataQueue);
             Thread consumerThread = new Thread(consumer);
             consumerThread.start();
             threads.add(consumerThread);
+            consumers.add(consumer);
         }
 
-        // let threads run for two seconds
+        // let threads run for ten seconds
-        sleep(2000);
+        sleep(10000);
 
-        // Stop threads
+        // stop threads
-        producer.stop();
+        consumers.forEach(Consumer::stop);
-        consumer.stop();
+        producers.forEach(Producer::stop);
 
         waitForAllThreadsToComplete(threads);
     }

core-java-modules/core-java-concurrency-advanced/src/main/java/com/baeldung/concurrent/phaser/LongRunningAction.java

@@ -7,31 +7,37 @@ import java.util.concurrent.Phaser;
 
 class LongRunningAction implements Runnable {
 
-    private static Logger log = LoggerFactory.getLogger(LongRunningAction.class);
+    private static final Logger log = LoggerFactory.getLogger(LongRunningAction.class);
-    private String threadName;
+    private final String threadName;
-    private Phaser ph;
+    private final Phaser ph;
 
     LongRunningAction(String threadName, Phaser ph) {
         this.threadName = threadName;
         this.ph = ph;
+
+        this.randomWait();
+
         ph.register();
+        log.info("Thread {} registered during phase {}", threadName, ph.getPhase());
     }
 
     @Override
     public void run() {
-        log.info("This is phase {}", ph.getPhase());
+        log.info("Thread {} BEFORE long running action in phase {}", threadName, ph.getPhase());
-        log.info("Thread {} before long running action", threadName);
+        ph.arriveAndAwaitAdvance();
-        
+
+        randomWait();
+
+        log.info("Thread {} AFTER long running action in phase {}", threadName, ph.getPhase());
+        ph.arriveAndDeregister();
+    }
+
+    // Simulating real work
+    private void randomWait() {
         try {
-            Thread.sleep(2000);
+            Thread.sleep((long) (Math.random() * 100));
         } catch (InterruptedException e) {
             e.printStackTrace();
         }
-
-        log.debug("Thread {} action completed and waiting for others", threadName);
-        ph.arriveAndAwaitAdvance();
-        log.debug("Thread {} proceeding in phase {}", threadName, ph.getPhase());
-        
-        ph.arriveAndDeregister();
     }
 }

core-java-modules/core-java-concurrency-advanced/src/test/java/com/baeldung/concurrent/phaser/PhaserUnitTest.java

@@ -7,8 +7,6 @@ import org.junit.runners.MethodSorters;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
 import java.util.concurrent.Phaser;
 
 import static junit.framework.TestCase.assertEquals;
@@ -16,38 +14,32 @@ import static junit.framework.TestCase.assertEquals;
 @FixMethodOrder(MethodSorters.NAME_ASCENDING)
 public class PhaserUnitTest {
 
-    private static Logger log = LoggerFactory.getLogger(PhaserUnitTest.class);
+    private static final Logger log = LoggerFactory.getLogger(PhaserUnitTest.class);
 
     @Test
-    public void givenPhaser_whenCoordinateWorksBetweenThreads_thenShouldCoordinateBetweenMultiplePhases() {
+    public void givenPhaser_whenCoordinateWorksBetweenThreads_thenShouldCoordinateBetweenMultiplePhases() throws InterruptedException {
-        //given
-        ExecutorService executorService = Executors.newCachedThreadPool();
         Phaser ph = new Phaser(1);
         assertEquals(0, ph.getPhase());
 
-        //when
+        new Thread(new LongRunningAction("thread-1", ph)).start();
-        executorService.submit(new LongRunningAction("thread-1", ph));
+        new Thread(new LongRunningAction("thread-2", ph)).start();
-        executorService.submit(new LongRunningAction("thread-2", ph));
+        new Thread(new LongRunningAction("thread-3", ph)).start();
-        executorService.submit(new LongRunningAction("thread-3", ph));
 
-        //then
+        log.info("Thread {} waiting for others", Thread.currentThread().getName());
-        log.debug("Thread {} waiting for others", Thread.currentThread().getName());
         ph.arriveAndAwaitAdvance();
-        log.debug("Thread {} proceeding in phase {}", Thread.currentThread().getName(), ph.getPhase());
+        log.info("Thread {} proceeding in phase {}", Thread.currentThread().getName(), ph.getPhase());
-        
         assertEquals(1, ph.getPhase());
 
-        //and
+        new Thread(new LongRunningAction("thread-4", ph)).start();
-        executorService.submit(new LongRunningAction("thread-4", ph));
+        new Thread(new LongRunningAction("thread-5", ph)).start();
-        executorService.submit(new LongRunningAction("thread-5", ph));
 
-        log.debug("Thread {} waiting for others", Thread.currentThread().getName());
+        log.info("Thread {} waiting for new phase", Thread.currentThread().getName());
         ph.arriveAndAwaitAdvance();
-        log.debug("Thread {} proceeding in phase {}", Thread.currentThread().getName(), ph.getPhase());
+        log.info("Thread {} proceeding in phase {}", Thread.currentThread().getName(), ph.getPhase());
-        
         assertEquals(2, ph.getPhase());
 
-
         ph.arriveAndDeregister();
+        Thread.sleep(1000);
+        assertEquals(true, ph.isTerminated());
     }
 }

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

@@ -11,4 +11,5 @@ This module contains articles about basic Java concurrency
 - [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)
 - [How to Get Notified When a Task Completes in Java Executors](https://www.baeldung.com/java-executors-task-completed-notification)
+- [Difference Between Future, CompletableFuture, and Rxjava’s Observable](https://www.baeldung.com/java-future-completablefuture-rxjavas-observable)
 - [[Next -->]](/core-java-modules/core-java-concurrency-basic-2)

core-java-modules/core-java-concurrency-collections-2/src/test/java/com/baeldung/hashtableandconcurrenthashmap/BenchMarkRunner.java

@@ -0,0 +1,73 @@
+package com.baeldung.hashtableandconcurrenthashmap;
+
+import org.openjdk.jmh.annotations.*;
+import org.openjdk.jmh.infra.Blackhole;
+import org.openjdk.jmh.runner.Runner;
+import org.openjdk.jmh.runner.options.Options;
+import org.openjdk.jmh.runner.options.OptionsBuilder;
+
+import java.util.Hashtable;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.TimeUnit;
+
+@BenchmarkMode(Mode.AverageTime)
+@OutputTimeUnit(TimeUnit.MILLISECONDS)
+@State(Scope.Benchmark)
+@Fork(value = 1)
+@Warmup(iterations = 3)
+@Measurement(iterations = 5)
+@Threads(10) // 10 threads for the test
+public class BenchMarkRunner {
+    private Hashtable<String, Integer> hashTable;
+    private ConcurrentHashMap<String, Integer> concurrentHashMap;
+
+    @Setup(Level.Trial)
+    public void setup() {
+        hashTable = new Hashtable<>();
+        concurrentHashMap = new ConcurrentHashMap<>();
+    }
+
+    @Benchmark
+    @Group("hashtable")
+    public void benchmarkHashtablePut() {
+        for (int i = 0; i < 10000; i++) {
+            hashTable.put(String.valueOf(i), i);
+        }
+    }
+
+    @Benchmark
+    @Group("hashtable")
+    public void benchmarkHashtableGet(Blackhole blackhole) {
+        for (int i = 0; i < 10000; i++) {
+            Integer value = hashTable.get(String.valueOf(i));
+            blackhole.consume(value);
+        }
+    }
+
+    @Benchmark
+    @Group("concurrentHashMap")
+    public void benchmarkConcurrentHashMapPut() {
+        for (int i = 0; i < 10000; i++) {
+            concurrentHashMap.put(String.valueOf(i), i);
+        }
+    }
+
+    @Benchmark
+    @Group("concurrentHashMap")
+    public void benchmarkConcurrentHashMapGet(Blackhole blackhole) {
+        for (int i = 0; i < 10000; i++) {
+            Integer value = concurrentHashMap.get(String.valueOf(i));
+            blackhole.consume(value);
+        }
+    }
+
+    public static void main(String[] args) throws Exception {
+        Options options = new OptionsBuilder()
+          .include(BenchMarkRunner.class.getSimpleName())
+          .shouldFailOnError(true)
+          .shouldDoGC(true)
+          .jvmArgs("-server")
+          .build();
+        new Runner(options).run();
+    }
+}

core-java-modules/core-java-concurrency-collections-2/src/test/java/com/baeldung/hashtableandconcurrenthashmap/ConcurrentHashMapUnitTest.java

@@ -0,0 +1,62 @@
+package com.baeldung.hashtableandconcurrenthashmap;
+
+import org.junit.Test;
+import java.util.ConcurrentModificationException;
+import java.util.Iterator;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.atomic.AtomicBoolean;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+public class ConcurrentHashMapUnitTest {
+    @Test
+    public void givenEmptyConcurrentHashMap_whenValuesAreAdded_thenValuesCanBeRetrieved() {
+        ConcurrentHashMap<String, String> concurrentHashMap = new ConcurrentHashMap<>();
+        concurrentHashMap.put("Key1", "1");
+        concurrentHashMap.put("Key2", "2");
+        concurrentHashMap.putIfAbsent("Key3", "3");
+        String value = concurrentHashMap.get("Key2");
+
+        assertEquals("1", concurrentHashMap.get("Key1"));
+        assertEquals("2", value);
+        assertEquals("3", concurrentHashMap.get("Key3"));
+    }
+    @Test
+    public void givenPopulatedConcurrentHashMap_whenModifiedDuringIteration_thenShouldNotThrowConcurrentModificationException() throws InterruptedException {
+        ConcurrentHashMap<String, Integer> concurrentHashMap = new ConcurrentHashMap<>();
+        concurrentHashMap.put("Key1", 1);
+        concurrentHashMap.put("Key2", 2);
+        concurrentHashMap.put("Key3", 3);
+        AtomicBoolean exceptionCaught = new AtomicBoolean(false);
+
+        Thread iteratorThread = new Thread(() -> {
+            Iterator<String> it = concurrentHashMap.keySet().iterator();
+            try {
+                while (it.hasNext()) {
+                    it.next();
+                    Thread.sleep(100);
+                }
+            } catch (ConcurrentModificationException e) {
+                exceptionCaught.set(true);
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+        });
+
+        Thread modifierThread = new Thread(() -> {
+            try {
+                Thread.sleep(50);
+                concurrentHashMap.put("Key4", 4);
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+        });
+
+        iteratorThread.start();
+        modifierThread.start();
+
+        iteratorThread.join();
+        modifierThread.join();
+
+        assertFalse(exceptionCaught.get());
+    }
+}

core-java-modules/core-java-concurrency-collections-2/src/test/java/com/baeldung/hashtableandconcurrenthashmap/HashtableUnitTest.java

@@ -0,0 +1,63 @@
+package com.baeldung.hashtableandconcurrenthashmap;
+
+import org.junit.Test;
+import java.util.ConcurrentModificationException;
+import java.util.Hashtable;
+import java.util.Iterator;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+public class HashtableUnitTest {
+    @Test
+    public void givenEmptyHashtable_whenValuesAreAdded_thenValuesCanBeRetrieved() {
+        Hashtable<String, String> hashtable = new Hashtable<>();
+        hashtable.put("Key1", "1");
+        hashtable.put("Key2", "2");
+        hashtable.putIfAbsent("Key3", "3");
+        String value = hashtable.get("Key2");
+
+        assertEquals("1", hashtable.get("Key1"));
+        assertEquals("2", value);
+        assertEquals("3", hashtable.get("Key3"));
+    }
+    @Test
+    public void givenPopulatedHashtable_whenModifiedDuringIteration_thenShouldThrowConcurrentModificationException() throws InterruptedException {
+        Hashtable<String, Integer> hashtable = new Hashtable<>();
+        hashtable.put("Key1", 1);
+        hashtable.put("Key2", 2);
+        hashtable.put("Key3", 3);
+        AtomicBoolean exceptionCaught = new AtomicBoolean(false);
+
+        Thread iteratorThread = new Thread(() -> {
+            Iterator<String> it = hashtable.keySet().iterator();
+            try {
+                while (it.hasNext()) {
+                    it.next();
+                    Thread.sleep(100);
+                }
+            } catch (ConcurrentModificationException e) {
+                exceptionCaught.set(true);
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+        });
+
+        Thread modifierThread = new Thread(() -> {
+            try {
+                Thread.sleep(50);
+                hashtable.put("Key4", 4);
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+        });
+
+        iteratorThread.start();
+        modifierThread.start();
+
+        iteratorThread.join();
+        modifierThread.join();
+
+        assertTrue(exceptionCaught.get());
+    }
+}