Merge branch 'master' of https://github.com/eugenp/tutorials

algorithms-modules/algorithms-miscellaneous-7/src/main/java/com/baeldung/algorithms/stringrotation/StringRotation.java

@@ -0,0 +1,123 @@
+package com.baeldung.algorithms.stringrotation;
+
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Queue;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+public class StringRotation {
+
+    public static boolean doubledOriginContainsRotation(String origin, String rotation) {
+        if (origin.length() == rotation.length()) {
+            return origin.concat(origin)
+              .contains(rotation);
+        }
+
+        return false;
+    }
+
+    public static boolean isRotationUsingCommonStartWithOrigin(String origin, String rotation) {
+
+        if (origin.length() == rotation.length()) {
+
+            List<Integer> indexes = IntStream.range(0, origin.length())
+              .filter(i -> rotation.charAt(i) == origin.charAt(0))
+              .boxed()
+              .collect(Collectors.toList());
+
+            for (int startingAt : indexes) {
+                if (isRotation(startingAt, rotation, origin)) {
+                    return true;
+                }
+            }
+        }
+
+        return false;
+    }
+
+    static boolean isRotation(int startingAt, String rotation, String origin) {
+
+        for (int i = 0; i < origin.length(); i++) {
+            if (rotation.charAt((startingAt + i) % origin.length()) != origin.charAt(i)) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    public static boolean isRotationUsingQueue(String origin, String rotation) {
+
+        if (origin.length() == rotation.length()) {
+            return checkWithQueue(origin, rotation);
+        }
+
+        return false;
+    }
+
+    static boolean checkWithQueue(String origin, String rotation) {
+
+        if (origin.length() == rotation.length()) {
+
+            Queue<Character> originQueue = getCharactersQueue(origin);
+
+            Queue<Character> rotationQueue = getCharactersQueue(rotation);
+
+            int k = rotation.length();
+            while (k > 0 && null != rotationQueue.peek()) {
+                k--;
+                char ch = rotationQueue.peek();
+                rotationQueue.remove();
+                rotationQueue.add(ch);
+                if (rotationQueue.equals(originQueue)) {
+                    return true;
+                }
+            }
+        }
+
+        return false;
+    }
+
+    static Queue<Character> getCharactersQueue(String origin) {
+        return origin.chars()
+          .mapToObj(c -> (char) c)
+          .collect(Collectors.toCollection(LinkedList::new));
+    }
+
+    public static boolean isRotationUsingSuffixAndPrefix(String origin, String rotation) {
+
+        if (origin.length() == rotation.length()) {
+            return checkPrefixAndSuffix(origin, rotation);
+        }
+
+        return false;
+    }
+
+    static boolean checkPrefixAndSuffix(String origin, String rotation) {
+        if (origin.length() == rotation.length()) {
+
+            for (int i = 0; i < origin.length(); i++) {
+                if (origin.charAt(i) == rotation.charAt(0)) {
+                    if (checkRotationPrefixWithOriginSuffix(origin, rotation, i)) {
+                        if (checkOriginPrefixWithRotationSuffix(origin, rotation, i))
+                            return true;
+                    }
+                }
+            }
+
+        }
+
+        return false;
+    }
+
+    private static boolean checkRotationPrefixWithOriginSuffix(String origin, String rotation, int i) {
+        return origin.substring(i)
+          .equals(rotation.substring(0, origin.length() - i));
+    }
+
+    private static boolean checkOriginPrefixWithRotationSuffix(String origin, String rotation, int i) {
+        return origin.substring(0, i)
+          .equals(rotation.substring(origin.length() - i));
+    }
+}

algorithms-modules/algorithms-miscellaneous-7/src/test/java/com/baeldung/algorithms/stringrotation/StringRotationUnitTest.java

@@ -0,0 +1,61 @@
+package com.baeldung.algorithms.stringrotation;
+
+import static com.baeldung.algorithms.stringrotation.StringRotation.doubledOriginContainsRotation;
+import static com.baeldung.algorithms.stringrotation.StringRotation.isRotationUsingCommonStartWithOrigin;
+import static com.baeldung.algorithms.stringrotation.StringRotation.isRotationUsingQueue;
+import static com.baeldung.algorithms.stringrotation.StringRotation.isRotationUsingSuffixAndPrefix;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.junit.jupiter.api.Test;
+
+class StringRotationUnitTest {
+
+    @Test
+    void givenOriginAndRotationInput_whenCheckIfOriginContainsRotation_thenIsRotation() {
+        assertTrue(doubledOriginContainsRotation("abcd", "cdab"));
+        assertTrue(doubledOriginContainsRotation("abcd", "abcd"));
+    }
+
+    @Test
+    void givenOriginAndRotationInput_whenCheckIfOriginContainsRotation_thenNoRotation() {
+        assertFalse(doubledOriginContainsRotation("abcd", "bbbb"));
+        assertFalse(doubledOriginContainsRotation("abcd", "abcde"));
+    }
+
+    @Test
+    void givenOriginAndRotationInput_whenCheckingCommonStartWithOrigin_thenIsRotation() {
+        assertTrue(isRotationUsingCommonStartWithOrigin("abcd", "cdab"));
+        assertTrue(isRotationUsingCommonStartWithOrigin("abcd", "abcd"));
+    }
+
+    @Test
+    void givenOriginAndRotationInput_whenCheckingCommonStartWithOrigin_thenNoRotation() {
+        assertFalse(isRotationUsingCommonStartWithOrigin("abcd", "bbbb"));
+        assertFalse(isRotationUsingCommonStartWithOrigin("abcd", "abcde"));
+    }
+
+    @Test
+    void givenOriginAndRotationInput_whenCheckingUsingQueues_thenIsRotation() {
+        assertTrue(isRotationUsingQueue("abcd", "cdab"));
+        assertTrue(isRotationUsingQueue("abcd", "abcd"));
+    }
+
+    @Test
+    void givenOriginAndRotationInput_whenCheckingUsingQueues_thenNoRotation() {
+        assertFalse(isRotationUsingQueue("abcd", "bbbb"));
+        assertFalse(isRotationUsingQueue("abcd", "abcde"));
+    }
+
+    @Test
+    void givenOriginAndRotationInput_whenCheckingUsingSuffixAndPrefix_thenIsRotation() {
+        assertTrue(isRotationUsingSuffixAndPrefix("abcd", "cdab"));
+        assertTrue(isRotationUsingSuffixAndPrefix("abcd", "abcd"));
+    }
+
+    @Test
+    void givenOriginAndRotationInput_whenCheckingUsingSuffixAndPrefix_thenNoRotation() {
+        assertFalse(isRotationUsingSuffixAndPrefix("abcd", "bbbb"));
+        assertFalse(isRotationUsingSuffixAndPrefix("abcd", "abcde"));
+    }
+}

apache-libraries-2/pom.xml

@@ -19,10 +19,29 @@
             <artifactId>validation-api</artifactId>
             <version>${javax.validation.validation-api.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.apache.camel</groupId>
+            <artifactId>camel-core</artifactId>
+            <version>${camel.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.apache.camel</groupId>
+            <artifactId>camel-test-junit5</artifactId>
+            <version>${camel.version}</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.apache.camel</groupId>
+            <artifactId>camel-main</artifactId>
+            <version>${camel.version}</version>
+        </dependency>
     </dependencies>
 
     <properties>
         <javax.validation.validation-api.version>2.0.1.Final</javax.validation.validation-api.version>
+        <camel.version>4.3.0</camel.version>
     </properties>
 
 </project>

apache-libraries-2/src/main/java/com/baeldung/dynamicrouter/DynamicRouterBean.java

@@ -0,0 +1,29 @@
+package com.baeldung.dynamicrouter;
+
+import org.apache.camel.ExchangeProperties;
+
+import java.util.Map;
+
+public class DynamicRouterBean {
+    public String route(String body, @ExchangeProperties Map<String, Object> properties) {
+        int invoked = (int) properties.getOrDefault("invoked", 0) + 1;
+
+        properties.put("invoked", invoked);
+
+        if (invoked == 1) {
+            switch (body.toLowerCase()) {
+                case "mock":
+                    return "mock:dynamicRouter";
+                case "direct":
+                    return "mock:directDynamicRouter";
+                case "seda":
+                    return "mock:sedaDynamicRouter";
+                case "file":
+                    return "mock:fileDynamicRouter";
+                default:
+                    break;
+            }
+        }
+        return null;
+    }
+}

apache-libraries-2/src/main/java/com/baeldung/dynamicrouter/DynamicRouterRoute.java

@@ -0,0 +1,13 @@
+package com.baeldung.dynamicrouter;
+
+import org.apache.camel.builder.RouteBuilder;
+
+public class DynamicRouterRoute extends RouteBuilder {
+
+    @Override
+    public void configure() {
+
+        from("direct:dynamicRouter").dynamicRouter(method(DynamicRouterBean.class, "route"));
+
+    }
+}

apache-libraries-2/src/main/resources/logback.xml

@@ -10,4 +10,6 @@
     <root level="INFO">
         <appender-ref ref="STDOUT" />
     </root>
+
+    <logger name="org.apache.camel.impl.engine" level="WARN"/>
 </configuration>

apache-libraries-2/src/test/java/dynamicrouter/DynamicRouterRouteUnitTest.java

@@ -0,0 +1,61 @@
+package dynamicrouter;
+
+import com.baeldung.dynamicrouter.DynamicRouterRoute;
+import org.apache.camel.RoutesBuilder;
+import org.apache.camel.component.mock.MockEndpoint;
+import org.apache.camel.test.junit5.CamelTestSupport;
+import org.junit.jupiter.api.Test;
+
+public class DynamicRouterRouteUnitTest extends CamelTestSupport {
+
+    @Override
+    protected RoutesBuilder createRouteBuilder() {
+        return new DynamicRouterRoute();
+    }
+
+    @Test
+    void givenDynamicRouter_whenMockEndpointExpectedMessageCountOneAndMockAsMessageBody_thenMessageSentToDynamicRouter() throws InterruptedException {
+
+        MockEndpoint mockDynamicEndpoint = getMockEndpoint("mock:dynamicRouter");
+        mockDynamicEndpoint.expectedMessageCount(1);
+
+        template.send("direct:dynamicRouter", exchange -> exchange.getIn()
+            .setBody("mock"));
+        MockEndpoint.assertIsSatisfied(context);
+    }
+
+    @Test
+    void givenDynamicRouter_whenMockEndpointExpectedMessageCountOneAndDirectAsMessageBody_thenMessageSentToDynamicRouter() throws InterruptedException {
+
+        MockEndpoint mockDynamicEndpoint = context.getEndpoint("mock:directDynamicRouter", MockEndpoint.class);
+        mockDynamicEndpoint.expectedMessageCount(1);
+
+        template.send("direct:dynamicRouter", exchange -> exchange.getIn()
+            .setBody("direct"));
+
+        MockEndpoint.assertIsSatisfied(context);
+    }
+
+    @Test
+    void givenDynamicRouter_whenMockEndpointExpectedMessageCountOneAndSedaAsMessageBody_thenMessageSentToDynamicRouter() throws InterruptedException {
+
+        MockEndpoint mockDynamicEndpoint = context.getEndpoint("mock:sedaDynamicRouter", MockEndpoint.class);
+        mockDynamicEndpoint.expectedMessageCount(1);
+
+        template.send("direct:dynamicRouter", exchange -> exchange.getIn()
+            .setBody("seda"));
+        MockEndpoint.assertIsSatisfied(context);
+    }
+
+    @Test
+    void givenDynamicRouter_whenMockEndpointExpectedMessageCountOneAndBookAsMessageBody_thenMessageSentToDynamicRouter() throws InterruptedException {
+
+        MockEndpoint mockDynamicEndpoint = getMockEndpoint("mock:fileDynamicRouter");
+        mockDynamicEndpoint.expectedMessageCount(1);
+
+        template.send("direct:dynamicRouter", exchange -> exchange.getIn()
+            .setBody("file"));
+        MockEndpoint.assertIsSatisfied(context);
+    }
+
+}

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

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
+            </pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+
+    <logger name="ch.qos.logback.classic.joran.action" level="WARN"/>
+</configuration>

core-groovy-modules/core-groovy/src/test/groovy/com/baeldung/io/TraverseFileTreeUnitTest.groovy

@@ -1,61 +1,71 @@
 package com.baeldung.io
 
-import org.junit.Test
-
 import groovy.io.FileType
 import groovy.io.FileVisitResult
+import org.junit.Test
+
+import static org.junit.Assert.assertTrue
 
 class TraverseFileTreeUnitTest {
     @Test
     void whenUsingEachFile_filesAreListed() {
+        var files = []
         new File('src/main/resources').eachFile { file ->
-            println file.name
+            files.add(file.name)
         }
+        assertTrue(files.size() > 1)
     }
     
     @Test(expected = IllegalArgumentException)
     void whenUsingEachFileOnAFile_anErrorOccurs() {
+        var files = []
         new File('src/main/resources/ioInput.txt').eachFile { file ->
-            println file.name
+            files.add(file.name)
         }
     }
     
     @Test
     void whenUsingEachFileMatch_filesAreListed() {
+        var files = []
         new File('src/main/resources').eachFileMatch(~/io.*\.txt/) { file ->
-            println file.name
+            files.add(file.name)
         }
     }
-    
+
     @Test
     void whenUsingEachFileRecurse_thenFilesInSubfoldersAreListed() {
+        var files = []
         new File('src/main').eachFileRecurse(FileType.FILES) { file ->
-            println "$file.parent $file.name"
+            files.add("$file.parent $file.name")
         }
     }
-    
+
     @Test
     void whenUsingEachFileRecurse_thenDirsInSubfoldersAreListed() {
+        var files = []
         new File('src/main').eachFileRecurse(FileType.DIRECTORIES) { file ->
-            println "$file.parent $file.name"
+            files.add("$file.parent $file.name")
         }
     }
-    
+
     @Test
     void whenUsingEachDirRecurse_thenDirsAndSubDirsAreListed() {
+        var files = []
         new File('src/main').eachDirRecurse { dir ->
-            println "$dir.parent $dir.name"
+            files.add("$dir.parent $dir.name")
         }
     }
-    
+
     @Test
     void whenUsingTraverse_thenDirectoryIsTraversed() {
+        var files = []
         new File('src/main').traverse { file ->
             if (file.directory && file.name == 'groovy') {
                 FileVisitResult.SKIP_SUBTREE
             } else {
-                println "$file.parent - $file.name"
+                files.add("$file.parent - $file.name")
             }
         }
+        assertTrue(files.size() > 1)
     }
 }

core-groovy-modules/core-groovy/src/test/groovy/com/baeldung/stringtypes/DollarSlashyString.groovy

@@ -2,6 +2,8 @@ package groovy.com.baeldung.stringtypes
 
 import org.junit.Test
 
+import static org.junit.Assert.assertFalse
+
 class DollarSlashyString {
 
     @Test
@@ -19,6 +21,7 @@ class DollarSlashyString {
             - $/$$
         /$
 
-        print(dollarSlashy)
+        //print(dollarSlashy)
+        assertFalse(dollarSlashy.isEmpty())
     }
 }

core-java-modules/core-java-18/src/main/java/com/baeldung/simplewebserver/WebServer.java

@@ -0,0 +1,59 @@
+package com.baeldung.simplewebserver;
+
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.nio.file.Path;
+import java.util.function.Predicate;
+
+import com.sun.net.httpserver.Filter;
+import com.sun.net.httpserver.Headers;
+import com.sun.net.httpserver.HttpHandler;
+import com.sun.net.httpserver.HttpHandlers;
+import com.sun.net.httpserver.HttpServer;
+import com.sun.net.httpserver.Request;
+import com.sun.net.httpserver.SimpleFileServer;
+
+public class WebServer {
+
+    private final InetSocketAddress address = new InetSocketAddress(8080);
+    private final Path path = Path.of("/");
+
+    public static void main(String[] args) {
+        WebServer webServer = new WebServer();
+        HttpServer server = webServer.createWithHandler401Response();
+        server.start();
+    }
+
+    private HttpServer createBasic() {
+        return SimpleFileServer.createFileServer(address, path, SimpleFileServer.OutputLevel.VERBOSE);
+    }
+
+    private HttpServer createWithHandler() throws IOException {
+        HttpServer server = SimpleFileServer.createFileServer(address, path, SimpleFileServer.OutputLevel.VERBOSE);
+        HttpHandler handler = SimpleFileServer.createFileHandler(Path.of("/Users"));
+        server.createContext("/test", handler);
+        return server;
+    }
+
+    private HttpServer createWithHandler401Response() {
+        Predicate<Request> findAllowedPath = r -> r.getRequestURI()
+          .getPath()
+          .equals("/test/allowed");
+
+        HttpHandler allowedResponse = HttpHandlers.of(200, Headers.of("Allow", "GET"), "Welcome");
+        HttpHandler deniedResponse = HttpHandlers.of(401, Headers.of("Deny", "GET"), "Denied");
+
+        HttpHandler handler = HttpHandlers.handleOrElse(findAllowedPath, allowedResponse, deniedResponse);
+
+        HttpServer server = SimpleFileServer.createFileServer(address, path, SimpleFileServer.OutputLevel.VERBOSE);
+        server.createContext("/test", handler);
+        return server;
+    }
+
+    private HttpServer createWithFilter() throws IOException {
+        Filter filter = SimpleFileServer.createOutputFilter(System.out, SimpleFileServer.OutputLevel.INFO);
+        HttpHandler handler = SimpleFileServer.createFileHandler(Path.of("/Users"));
+        return HttpServer.create(new InetSocketAddress(8080), 10, "/test", handler, filter);
+    }
+
+}

core-java-modules/core-java-collections/src/test/java/com/baeldung/hashtable/HashtableUnitTest.java

@@ -60,14 +60,15 @@ public class HashtableUnitTest {
         table.put(new Word("dog"), "another animal");
 
         Iterator<Word> it = table.keySet().iterator();
-        System.out.println("iterator created");
+        // System.out.println("iterator created");
 
         table.remove(new Word("dog"));
-        System.out.println("element removed");
+        // System.out.println("element removed");
 
         while (it.hasNext()) {
             Word key = it.next();
-            System.out.println(table.get(key));
+            // System.out.println(table.get(key));
+            assertNotNull(table.get(key));
         }
     }
 
@@ -85,12 +86,13 @@ public class HashtableUnitTest {
         table.put(new Word("8"), "eight");
 
         Enumeration<Word> enumKey = table.keys();
-        System.out.println("Enumeration created");
+        // System.out.println("Enumeration created");
         table.remove(new Word("1"));
-        System.out.println("element removed");
+        // System.out.println("element removed");
         while (enumKey.hasMoreElements()) {
             Word key = enumKey.nextElement();
-            System.out.println(table.get(key));
+            // System.out.println(table.get(key));
+            assertNotNull(table.get(key));
         }
     }
 
@@ -110,7 +112,8 @@ public class HashtableUnitTest {
         Iterator<Map.Entry<Word, String>> it = table.entrySet().iterator();
         while (it.hasNext()) {
             Map.Entry<Word, String> entry = it.next();
-            System.out.println(entry.getValue());
+            // System.out.println(entry.getValue());
+            assertNotNull(entry.getValue());
         }
     }
 

core-java-modules/core-java-concurrency-2/src/main/java/com/baeldung/runvssupply/RunAndSupplyCompare.java

@@ -0,0 +1,79 @@
+package com.baeldung.runvssupply;
+
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+
+public class RunAndSupplyCompare {
+
+    public static void main(String args[]) throws ExecutionException, InterruptedException {
+        chainingOperationCompare();
+    }
+
+    public static void inputAndReturnCompare() throws ExecutionException, InterruptedException {
+        CompletableFuture<Void> runAsyncFuture = CompletableFuture.runAsync(() -> {
+            // Perform non-result producing task
+            System.out.println("Task executed asynchronously");
+        });
+
+        CompletableFuture<String> supplyAsyncFuture = CompletableFuture.supplyAsync(() -> {
+            // Perform result-producing task
+            return "Result of the asynchronous computation";
+        });
+        // Get the result later
+        String result = supplyAsyncFuture.get();
+        System.out.println("Result: " + result);
+    }
+
+    public static void exceptionHandlingCompare() {
+        CompletableFuture<Void> runAsyncFuture = CompletableFuture.runAsync(() -> {
+            // Task that may throw an exception
+            throw new RuntimeException("Exception occurred in asynchronous task");
+        });
+        try {
+            runAsyncFuture.get();
+            // Exception will be thrown here
+        } catch (ExecutionException ex) {
+            Throwable cause = ex.getCause();
+            System.out.println("Exception caught: " + cause.getMessage());
+        } catch (InterruptedException e) {
+            throw new RuntimeException(e);
+        }
+
+        CompletableFuture<Object> supplyAsyncFuture = CompletableFuture.supplyAsync(() -> {
+                // Task that may throw an exception
+                throw new RuntimeException("Exception occurred in asynchronous task");
+            })
+            .exceptionally(ex -> {
+                // Exception handling logic
+                return "Default value";
+            });
+
+        Object result = supplyAsyncFuture.join();
+        // Get the result or default value
+        System.out.println("Result: " + result);
+    }
+
+    public static void chainingOperationCompare() {
+        CompletableFuture<Void> runAsyncFuture = CompletableFuture.runAsync(() -> {
+            // Perform non-result producing task
+            System.out.println("Task executed asynchronously");
+        });
+        runAsyncFuture.thenRun(() -> {
+            // Execute another task after the completion of runAsync()
+            System.out.println("Another task executed after runAsync() completes");
+        });
+
+        CompletableFuture<String> supplyAsyncFuture = CompletableFuture.supplyAsync(() -> {
+            // Perform result-producing task
+            return "Result of the asynchronous computation";
+        });
+        supplyAsyncFuture.thenApply(result -> {
+                // Transform the result
+                return result.toUpperCase();
+            })
+            .thenAccept(transformedResult -> {
+                // Consume the transformed result
+                System.out.println("Transformed Result: " + transformedResult);
+            });
+    }
+}

core-java-modules/core-java-concurrency-2/src/test/java/com/baeldung/concurrent/applyvsapplyasync/ThenApplyAndThenApplyAsyncUnitTest.java

@@ -0,0 +1,91 @@
+package com.baeldung.concurrent.applyvsapplyasync;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionException;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+public class ThenApplyAndThenApplyAsyncUnitTest {
+
+    @Test
+    public void givenCompletableFuture_whenUsingThenApply_thenResultIsAsExpected() {
+        CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> 5);
+        CompletableFuture<String> thenApplyResultFuture = future.thenApply(num -> "Result: " + num);
+
+        String thenApplyResult = thenApplyResultFuture.join();
+        assertEquals("Result: 5", thenApplyResult);
+    }
+
+    @Test
+    public void givenCompletableFuture_whenUsingThenApplyAsync_thenResultIsAsExpected() {
+        CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> 5);
+        CompletableFuture<String> thenApplyAsyncResultFuture = future.thenApplyAsync(num -> "Result: " + num);
+
+        String thenApplyAsyncResult = thenApplyAsyncResultFuture.join();
+        assertEquals("Result: 5", thenApplyAsyncResult);
+    }
+
+    @Test
+    public void givenCompletableFuture_whenUsingThenApply_thenExceptionIsPropagated() {
+        CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> 5);
+        CompletableFuture<String> resultFuture = future.thenApply(num -> "Result: " + num / 0);
+        assertThrows(CompletionException.class, () -> resultFuture.join());
+    }
+
+    @Test
+    public void givenCompletableFuture_whenUsingThenApply_thenExceptionIsHandledAsExpected() {
+        CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> 5);
+        CompletableFuture<String> resultFuture = future.thenApply(num -> "Result: " + num / 0);
+        try {
+            // Accessing the result
+            String result = resultFuture.join();
+            assertEquals("Result: 5", result);
+        } catch (CompletionException e) {
+            assertEquals("java.lang.ArithmeticException: / by zero", e.getMessage());
+            System.err.println("Exception caught: " + e.getMessage());
+        }
+    }
+
+    @Test
+    public void givenCompletableFuture_whenUsingThenApplyAsync_thenExceptionIsHandledAsExpected() {
+        CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> 5);
+        CompletableFuture<String> thenApplyAsyncResultFuture = future.thenApplyAsync(num -> "Result: " + num / 0);
+
+        String result = thenApplyAsyncResultFuture.handle((res, error) -> {
+                if (error != null) {
+                    // Handle the error appropriately, e.g., return a default value
+                    return "Error occurred";
+                } else {
+                    return res;
+                }
+            })
+            .join(); // Now join() won't throw the exception
+        assertEquals("Error occurred", result);
+    }
+
+    @Test
+    public void givenCompletableFutureWithExecutor_whenUsingThenApplyAsync_thenThreadExecutesAsExpected() {
+        ExecutorService customExecutor = Executors.newFixedThreadPool(4);
+
+        CompletableFuture<Integer> future = CompletableFuture.supplyAsync(() -> {
+            try {
+                Thread.sleep(2000);
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+            return 5;
+        }, customExecutor);
+
+        CompletableFuture<String> resultFuture = future.thenApplyAsync(num -> "Result: " + num, customExecutor);
+
+        String result = resultFuture.join();
+        assertEquals("Result: 5", result);
+
+        customExecutor.shutdown();
+    }
+}

core-java-modules/core-java-concurrency-simple/src/test/resources/logback.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
+            </pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>

core-java-modules/core-java-httpclient/src/test/resources/logback.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
+            </pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+
+    <logger name="org.eclipse.jetty.server.handler" level="WARN"/>
+    <logger name="org.mockserver.log" level="WARN"/>
+</configuration>

core-java-modules/core-java-security-4/src/main/java/com/baeldung/enablessldebug/SSLDebugLogger.java

@@ -23,9 +23,9 @@ public class SSLDebugLogger {
 
         try (BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream()))) {
             String line;
-            logger.info("Response from " + url + ":");
+            logger.debug("Response from " + url + ":");
             while ((line = reader.readLine()) != null) {
-                logger.info(line);
+                logger.debug(line);
             }
         }
     }

core-java-modules/core-java-security-4/src/test/resources/logback.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
+            </pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>

core-java-modules/core-java-string-algorithms-4/src/test/java/com/baeldung/string/chkstringinmirror/CheckStringEqualsMirrorReflectionUnitTest.java

@@ -0,0 +1,47 @@
+package com.baeldung.string.chkstringinmirror;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.Set;
+import java.util.stream.Collectors;
+
+import org.junit.jupiter.api.Test;
+
+public class CheckStringEqualsMirrorReflectionUnitTest {
+
+    private final static Set<Character> SYMMETRIC_LETTERS = Set.of('A', 'H', 'I', 'M', 'O', 'T', 'U', 'V', 'W', 'X', 'Y');
+
+    @Test
+    void whenCallingIsReflectionEqual_thenGetExpectedResults() {
+        assertFalse(isMirrorImageEqual("LOL"));
+        assertFalse(isMirrorImageEqual("AXY"));
+        assertFalse(isMirrorImageEqual("HUHU"));
+
+        assertTrue(isMirrorImageEqual(""));
+        assertTrue(isMirrorImageEqual("AAA"));
+        assertTrue(isMirrorImageEqual("HUH"));
+        assertTrue(isMirrorImageEqual("HIMMIH"));
+        assertTrue(isMirrorImageEqual("HIMIH"));
+    }
+
+
+    public boolean isMirrorImageEqual(String input) {
+        return containsOnlySymmetricLetters(input) && isPalindrome(input);
+    }
+
+    private boolean containsOnlySymmetricLetters(String input) {
+        Set<Character> characterSet = input.chars()
+            .mapToObj(c -> (char) c)
+            .collect(Collectors.toSet());
+        characterSet.removeAll(SYMMETRIC_LETTERS);
+        return characterSet.isEmpty();
+    }
+
+    private boolean isPalindrome(String input) {
+        String reversed = new StringBuilder(input).reverse()
+            .toString();
+        return input.equals(reversed);
+    }
+
+}

core-java-modules/core-java-string-operations-8/src/test/java/com/baeldung/checkifstringisbased64/CheckIfStringIsBased64UnitTest.java

@@ -0,0 +1,40 @@
+package com.baeldung.checkifstringisbased64;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.Base64;
+import java.util.regex.Pattern;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class CheckIfStringIsBased64UnitTest {
+
+    @Test
+    public void givenBase64EncodedString_whenDecoding_thenNoException() {
+        try {
+            Base64.getDecoder().decode("SGVsbG8gd29ybGQ=");
+            assertTrue(true);
+        } catch (IllegalArgumentException e) {
+            fail("Unexpected exception: " + e.getMessage());
+        }
+    }
+
+    @Test
+    public void givenNonBase64String_whenDecoding_thenCatchException() {
+        try {
+            Base64.getDecoder().decode("Hello world!");
+            fail("Expected IllegalArgumentException was not thrown");
+        } catch (IllegalArgumentException e) {
+            assertTrue(true);
+        }
+    }
+
+    @Test
+    public void givenString_whenOperatingRegex_thenCheckIfItIsBase64Encoded() {
+        Pattern BASE64_PATTERN = Pattern.compile(
+                "^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$"
+        );
+
+        assertTrue(BASE64_PATTERN.matcher("SGVsbG8gd29ybGQ=").matches());
+    }
+}

core-java-modules/core-java-string-operations-8/src/test/java/com/baeldung/finduniqueemails/FindUniqueEmailsUnitTest.java

@@ -0,0 +1,40 @@
+package com.baeldung.finduniqueemails;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class FindUniqueEmailsUnitTest {
+    String[] emailList = {"[email protected]", "[email protected]", "[email protected]", "[email protected]", "[email protected]"};
+    Set<String> expectedUniqueEmails = new HashSet<>();
+
+    FindUniqueEmailsUnitTest() {
+        expectedUniqueEmails.add("[email protected]");
+        expectedUniqueEmails.add("[email protected]");
+        expectedUniqueEmails.add("[email protected]");
+    }
+
+    @Test
+    public void givenEmailList_whenUsingStringManipulation_thenFindUniqueEmails() {
+        Set<String> uniqueEmails = new HashSet<>();
+        for (String email : emailList) {
+            uniqueEmails.add(email.toLowerCase());
+        }
+
+        assertEquals(expectedUniqueEmails, uniqueEmails);
+    }
+
+    @Test
+    public void givenEmailList_whenUsingJavaStreams_thenFindUniqueEmails() {
+        Set<String> uniqueEmails = Arrays.stream(emailList)
+                .map(String::toLowerCase)
+                .collect(Collectors.toSet());
+
+        assertEquals(expectedUniqueEmails, uniqueEmails);
+    }
+}

docker-modules/docker-compose/Dockerfile

@@ -1,4 +1,4 @@
-FROM openjdk:11
+FROM openjdk:17-alpine
 MAINTAINER baeldung.com
 COPY target/docker-compose-0.0.1-SNAPSHOT.jar app.jar
 ENTRYPOINT ["java","-jar","/app.jar"]

docker-modules/docker-compose/pom.xml

@@ -8,9 +8,9 @@
 
     <parent>
         <groupId>com.baeldung</groupId>
-        <artifactId>parent-boot-2</artifactId>
+        <artifactId>parent-boot-3</artifactId>
         <version>0.0.1-SNAPSHOT</version>
-        <relativePath>../../parent-boot-2</relativePath>
+        <relativePath>../../parent-boot-3</relativePath>
     </parent>
 
     <dependencies>

jackson-modules/jackson-custom-conversions/javatypefromclassinjava/JavaTypeFromClassUnitTest.java

@@ -0,0 +1,38 @@
+package com.baeldung.javatypefromclassinjava;
+
+import com.fasterxml.jackson.databind.JavaType;
+import com.fasterxml.jackson.databind.type.TypeFactory;
+import org.junit.Test;
+
+import static org.junit.Assert.assertNotNull;
+
+public class JavaTypeFromClassUnitTest {
+
+    @Test
+    public void givenGenericClass_whenCreatingJavaType_thenJavaTypeNotNull() {
+        Class<?> myClass = MyGenericClass.class;
+
+        JavaType javaType = TypeFactory.defaultInstance().constructType(myClass);
+
+        assertNotNull(javaType);
+    }
+
+    @Test
+    public void givenParametricType_whenCreatingJavaType_thenJavaTypeNotNull() {
+        Class<?> containerClass = Container.class;
+        Class<?> elementType = String.class;
+
+        JavaType javaType = TypeFactory.defaultInstance().constructParametricType(containerClass, elementType);
+
+        assertNotNull(javaType);
+    }
+
+    static class MyGenericClass<T> {
+        // Class implementation
+    }
+
+    static class Container<T> {
+        // Class implementation
+    }
+
+}

libraries-data-io/pom.xml

@@ -95,6 +95,12 @@
             <artifactId>protobuf-java</artifactId>
             <version>${google-protobuf.version}</version>
         </dependency>
+        <!-- jetcd core api -->
+        <dependency>
+            <groupId>io.etcd</groupId>
+            <artifactId>jetcd-core</artifactId>
+            <version>${jetcd-version}</version>
+        </dependency>
     </dependencies>
 
     <properties>
@@ -110,6 +116,7 @@
         <yamlbeans.version>1.15</yamlbeans.version>
         <apache-thrift.version>0.14.2</apache-thrift.version>
         <google-protobuf.version>3.17.3</google-protobuf.version>
+        <jetcd-version>0.7.7</jetcd-version>
     </properties>
 
-</project>
+</project>

libraries-data-io/src/main/java/com/baeldung/etcd/JetcdExample.java

@@ -0,0 +1,32 @@
+package com.baeldung.etcd;
+
+import java.util.concurrent.CompletableFuture;
+
+import io.etcd.jetcd.kv.GetResponse;
+import io.etcd.jetcd.ByteSequence;
+import io.etcd.jetcd.KV;
+import io.etcd.jetcd.Client;
+
+public class JetcdExample {
+    public static void main(String[] args) {
+        String etcdEndpoint = "http://localhost:2379";
+        ByteSequence key = ByteSequence.from("/mykey".getBytes());
+        ByteSequence value = ByteSequence.from("Hello, etcd!".getBytes());
+
+        try (Client client = Client.builder().endpoints(etcdEndpoint).build()) {
+            KV kvClient = client.getKVClient();
+            
+            // Put a key-value pair
+            kvClient.put(key, value).get();
+            
+            // Retrieve the value using CompletableFuture
+            CompletableFuture<GetResponse> getFuture = kvClient.get(key);
+            GetResponse response = getFuture.get();
+            
+            // Delete the key
+            kvClient.delete(key).get();
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}

lightrun/lightrun-tasks-service/pom.xml

@@ -48,6 +48,7 @@
         <dependency>
             <groupId>org.apache.activemq</groupId>
             <artifactId>artemis-jms-server</artifactId>
+            <version>${activemq.version}</version>
         </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
@@ -65,4 +66,8 @@
         </plugins>
     </build>
 
+    <properties>
+        <activemq.version>2.32.0</activemq.version>
+    </properties>
+
 </project>

persistence-modules/spring-boot-persistence-3/src/main/java/com/baeldung/findby/Account.java

@@ -0,0 +1,69 @@
+package com.baeldung.findby;
+
+import jakarta.persistence.*;
+
+import java.sql.Timestamp;
+
+@Entity
+@Table(name = "ACCOUNTS")
+public class Account {
+    @Id
+    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "accounts_seq")
+    @SequenceGenerator(name = "accounts_seq", sequenceName = "accounts_seq", allocationSize = 1)
+    @Column(name = "user_id")
+    private int userId;
+    private String username;
+    private String password;
+    private String email;
+    private Timestamp createdOn;
+    private Timestamp lastLogin;
+
+    @OneToOne
+    @JoinColumn(name = "permissions_id")
+    private Permission permission;
+
+    public String getUsername() {
+        return username;
+    }
+
+    public void setUsername(String username) {
+        this.username = username;
+    }
+
+    public void setPassword(String password) {
+        this.password = password;
+    }
+
+    public void setEmail(String email) {
+        this.email = email;
+    }
+
+    public Timestamp getCreatedOn() {
+        return createdOn;
+    }
+
+    public void setCreatedOn(Timestamp createdOn) {
+        this.createdOn = createdOn;
+    }
+
+    public void setLastLogin(Timestamp lastLogin) {
+        this.lastLogin = lastLogin;
+    }
+
+    public Permission getPermission() {
+        return permission;
+    }
+
+    public void setPermission(Permission permission) {
+        this.permission = permission;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+
+    @Override
+    public String toString() {
+        return "Account{" + "userId=" + userId + ", username='" + username + '\'' + ", password='" + password + '\'' + ", email='" + email + '\'' + ", createdOn=" + createdOn + ", lastLogin=" + lastLogin + ", permission=" + permission + '}';
+    }
+}

persistence-modules/spring-boot-persistence-3/src/main/java/com/baeldung/findby/AccountApplication.java

@@ -0,0 +1,11 @@
+package com.baeldung.findby;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class AccountApplication {
+    public static void main(String[] args) {
+        SpringApplication.run(AccountApplication.class, args);
+    }
+}

persistence-modules/spring-boot-persistence-3/src/main/java/com/baeldung/findby/AccountRepository.java

@@ -0,0 +1,18 @@
+package com.baeldung.findby;
+
+import java.util.List;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface AccountRepository extends JpaRepository<Account, Integer> {
+
+    Account findByEmail(String email);
+
+    Account findByUsernameAndEmail(String username, String email);
+
+    Account findByUsernameOrEmail(String username, String email);
+
+    List<Account> findByUsernameInOrEmailIn(List<String> usernames, List<String> emails);
+}