Spark graphx moved to a new project due to a incompatibility of scala compiler

libraries-2/README.md

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+## Relevant Articles: 
+
+- [A Guide to jBPM with Java](https://www.baeldung.com/jbpm-java)
+- [Guide to Classgraph Library](https://www.baeldung.com/classgraph)
+- [Create a Java Command Line Program with Picocli](https://www.baeldung.com/java-picocli-create-command-line-program)
+- [Guide to Java Parallel Collectors Library](https://www.baeldung.com/java-parallel-collectors)
+- [Templating with Handlebars](https://www.baeldung.com/handlebars)
+- [A Guide to Crawler4j](https://www.baeldung.com/crawler4j)
+- [Decode an OkHttp JSON Response](https://www.baeldung.com/okhttp-json-response)
+- [Key Value Store with Chronicle Map](https://www.baeldung.com/java-chronicle-map)
+- [Guide to MapDB](https://www.baeldung.com/mapdb)
+- [A Guide to Apache Mesos](https://www.baeldung.com/apache-mesos)

libraries-2/pom.xml

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+<?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>libraries-2</artifactId>
+    <name>libraries-2</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <repositories>
+        <repository>
+            <id>jboss-public-repository-group</id>
+            <name>JBoss Public Repository Group</name>
+            <url>http://repository.jboss.org/nexus/content/groups/public/</url>
+            <releases>
+                <enabled>true</enabled>
+                <updatePolicy>never</updatePolicy>
+            </releases>
+            <snapshots>
+                <enabled>true</enabled>
+                <updatePolicy>daily</updatePolicy>
+            </snapshots>
+        </repository>
+    </repositories>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.mapdb</groupId>
+            <artifactId>mapdb</artifactId>
+            <version>${mapdb.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.pivovarit</groupId>
+            <artifactId>parallel-collectors</artifactId>
+            <version>${parallel-collectors.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>io.github.classgraph</groupId>
+            <artifactId>classgraph</artifactId>
+            <version>${classgraph.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.jbpm</groupId>
+            <artifactId>jbpm-test</artifactId>
+            <version>${jbpm.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>info.picocli</groupId>
+            <artifactId>picocli</artifactId>
+            <version>${picocli.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter</artifactId>
+            <version>${spring-boot-starter.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>net.openhft</groupId>
+            <artifactId>chronicle-map</artifactId>
+            <version>${chronicle.map.version}</version>
+            <exclusions>
+                <exclusion>
+                    <groupId>com.sun.java</groupId>
+                    <artifactId>tools</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+        <!-- Dependencies for response decoder with okhttp -->
+        <dependency>
+            <groupId>com.squareup.okhttp3</groupId>
+            <artifactId>okhttp</artifactId>
+            <version>${okhttp.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+            <version>${jackson.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.google.code.gson</groupId>
+            <artifactId>gson</artifactId>
+            <version>${gson.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.squareup.okhttp3</groupId>
+            <artifactId>mockwebserver</artifactId>
+            <version>${mockwebserver.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>edu.uci.ics</groupId>
+            <artifactId>crawler4j</artifactId>
+            <version>${crawler4j.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.github.jknack</groupId>
+            <artifactId>handlebars</artifactId>
+            <version>${handlebars.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.apache.mesos</groupId>
+            <artifactId>mesos</artifactId>
+            <version>${mesos.library.version}</version>
+        </dependency>
+    </dependencies>
+
+    <properties>
+	    <mapdb.version>3.0.7</mapdb.version>
+        <assertj.version>3.6.2</assertj.version>
+        <classgraph.version>4.8.28</classgraph.version>
+        <jbpm.version>6.0.0.Final</jbpm.version>
+        <picocli.version>3.9.6</picocli.version>
+        <chronicle.map.version>3.17.2</chronicle.map.version>
+        <crawler4j.version>4.4.0</crawler4j.version>
+        <spring-boot-starter.version>2.1.4.RELEASE</spring-boot-starter.version>
+        <mesos.library.version>0.28.3</mesos.library.version>
+        <parallel-collectors.version>1.1.0</parallel-collectors.version>
+        <okhttp.version>3.14.2</okhttp.version>
+        <gson.version>2.8.5</gson.version>
+        <mockwebserver.version>3.14.2</mockwebserver.version>
+        <handlebars.version>4.1.2</handlebars.version>
+    </properties>
+</project>

libraries-2/src/main/java/com/baeldung/crawler4j/CrawlerStatistics.java

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+package com.baeldung.crawler4j;
+
+public class CrawlerStatistics {
+    private int processedPageCount = 0;
+    private int totalLinksCount = 0;
+    
+    public void incrementProcessedPageCount() {
+        processedPageCount++;
+    }
+    
+    public void incrementTotalLinksCount(int linksCount) {
+        totalLinksCount += linksCount;
+    }
+    
+    public int getProcessedPageCount() {
+        return processedPageCount;
+    }
+    
+    public int getTotalLinksCount() {
+        return totalLinksCount;
+    }
+}

libraries-2/src/main/java/com/baeldung/crawler4j/HtmlCrawler.java

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+package com.baeldung.crawler4j;
+
+import java.util.Set;
+import java.util.regex.Pattern;
+
+import edu.uci.ics.crawler4j.crawler.Page;
+import edu.uci.ics.crawler4j.crawler.WebCrawler;
+import edu.uci.ics.crawler4j.parser.HtmlParseData;
+import edu.uci.ics.crawler4j.url.WebURL;
+
+public class HtmlCrawler extends WebCrawler {
+
+    private final static Pattern EXCLUSIONS = Pattern.compile(".*(\\.(css|js|xml|gif|jpg|png|mp3|mp4|zip|gz|pdf))$");
+    
+    private CrawlerStatistics stats;
+    
+    public HtmlCrawler(CrawlerStatistics stats) {
+        this.stats = stats;
+    }
+
+    @Override
+    public boolean shouldVisit(Page referringPage, WebURL url) {
+        String urlString = url.getURL().toLowerCase();
+        return !EXCLUSIONS.matcher(urlString).matches() 
+            && urlString.startsWith("https://www.baeldung.com/");
+    }
+
+    @Override
+    public void visit(Page page) {
+        String url = page.getWebURL().getURL();
+        stats.incrementProcessedPageCount();
+
+        if (page.getParseData() instanceof HtmlParseData) {
+            HtmlParseData htmlParseData = (HtmlParseData) page.getParseData();
+            String title = htmlParseData.getTitle();
+            String text = htmlParseData.getText();
+            String html = htmlParseData.getHtml();
+            Set<WebURL> links = htmlParseData.getOutgoingUrls();
+            stats.incrementTotalLinksCount(links.size());
+
+            System.out.printf("Page with title '%s' %n", title);
+            System.out.printf("    Text length: %d %n", text.length());
+            System.out.printf("    HTML length: %d %n", html.length());
+            System.out.printf("    %d outbound links %n", links.size());
+        }
+    }
+
+}

libraries-2/src/main/java/com/baeldung/crawler4j/HtmlCrawlerController.java

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+package com.baeldung.crawler4j;
+
+import java.io.File;
+
+import edu.uci.ics.crawler4j.crawler.CrawlConfig;
+import edu.uci.ics.crawler4j.crawler.CrawlController;
+import edu.uci.ics.crawler4j.fetcher.PageFetcher;
+import edu.uci.ics.crawler4j.robotstxt.RobotstxtConfig;
+import edu.uci.ics.crawler4j.robotstxt.RobotstxtServer;
+
+public class HtmlCrawlerController {
+
+    public static void main(String[] args) throws Exception {
+        File crawlStorage = new File("src/test/resources/crawler4j");
+        CrawlConfig config = new CrawlConfig();
+        config.setCrawlStorageFolder(crawlStorage.getAbsolutePath());
+        config.setMaxDepthOfCrawling(2);
+
+        int numCrawlers = 12;
+
+        PageFetcher pageFetcher = new PageFetcher(config);
+        RobotstxtConfig robotstxtConfig = new RobotstxtConfig();
+        RobotstxtServer robotstxtServer = new RobotstxtServer(robotstxtConfig, pageFetcher);
+        CrawlController controller = new CrawlController(config, pageFetcher, robotstxtServer);
+
+        controller.addSeed("https://www.baeldung.com/");
+
+        CrawlerStatistics stats = new CrawlerStatistics();
+        CrawlController.WebCrawlerFactory<HtmlCrawler> factory = () -> new HtmlCrawler(stats);
+
+        controller.start(factory, numCrawlers);
+        System.out.printf("Crawled %d pages %n", stats.getProcessedPageCount());
+        System.out.printf("Total Number of outbound links = %d %n", stats.getTotalLinksCount());
+    }
+
+}

libraries-2/src/main/java/com/baeldung/crawler4j/ImageCrawler.java

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+package com.baeldung.crawler4j;
+
+import java.io.File;
+import java.util.regex.Pattern;
+
+import edu.uci.ics.crawler4j.crawler.Page;
+import edu.uci.ics.crawler4j.crawler.WebCrawler;
+import edu.uci.ics.crawler4j.parser.BinaryParseData;
+import edu.uci.ics.crawler4j.url.WebURL;
+
+public class ImageCrawler extends WebCrawler {
+    private final static Pattern EXCLUSIONS = Pattern.compile(".*(\\.(css|js|xml|gif|png|mp3|mp4|zip|gz|pdf))$");
+
+    private static final Pattern IMG_PATTERNS = Pattern.compile(".*(\\.(jpg|jpeg))$");
+
+    private File saveDir;
+
+    public ImageCrawler(File saveDir) {
+        this.saveDir = saveDir;
+    }
+
+    @Override
+    public boolean shouldVisit(Page referringPage, WebURL url) {
+        String urlString = url.getURL().toLowerCase();
+        if (EXCLUSIONS.matcher(urlString).matches()) {
+            return false;
+        }
+
+        if (IMG_PATTERNS.matcher(urlString).matches() 
+            || urlString.startsWith("https://www.baeldung.com/")) {
+            return true;
+        }
+
+        return false;
+    }
+
+    @Override
+    public void visit(Page page) {
+        String url = page.getWebURL().getURL();
+        if (IMG_PATTERNS.matcher(url).matches() 
+            && page.getParseData() instanceof BinaryParseData) {
+            String extension = url.substring(url.lastIndexOf("."));
+            int contentLength = page.getContentData().length;
+
+            System.out.printf("Extension is '%s' with content length %d %n", extension, contentLength);
+        }
+    }
+
+}

libraries-2/src/main/java/com/baeldung/crawler4j/ImageCrawlerController.java

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+package com.baeldung.crawler4j;
+
+import java.io.File;
+
+import edu.uci.ics.crawler4j.crawler.CrawlConfig;
+import edu.uci.ics.crawler4j.crawler.CrawlController;
+import edu.uci.ics.crawler4j.fetcher.PageFetcher;
+import edu.uci.ics.crawler4j.robotstxt.RobotstxtConfig;
+import edu.uci.ics.crawler4j.robotstxt.RobotstxtServer;
+
+public class ImageCrawlerController {
+
+    public static void main(String[] args) throws Exception {
+        File crawlStorage = new File("src/test/resources/crawler4j");
+        CrawlConfig config = new CrawlConfig();
+        config.setCrawlStorageFolder(crawlStorage.getAbsolutePath());
+        config.setIncludeBinaryContentInCrawling(true);
+        config.setMaxPagesToFetch(500);
+        
+        File saveDir = new File("src/test/resources/crawler4j");
+        
+        int numCrawlers = 12;
+        
+        PageFetcher pageFetcher = new PageFetcher(config);
+        RobotstxtConfig robotstxtConfig = new RobotstxtConfig();
+        RobotstxtServer robotstxtServer = new RobotstxtServer(robotstxtConfig, pageFetcher);
+        CrawlController controller = new CrawlController(config, pageFetcher, robotstxtServer);
+        
+        controller.addSeed("https://www.baeldung.com/");
+        
+        CrawlController.WebCrawlerFactory<ImageCrawler> factory = () -> new ImageCrawler(saveDir);
+        
+        controller.start(factory, numCrawlers);
+    }
+
+}

libraries-2/src/main/java/com/baeldung/crawler4j/MultipleCrawlerController.java

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+package com.baeldung.crawler4j;
+
+import java.io.File;
+
+import edu.uci.ics.crawler4j.crawler.CrawlConfig;
+import edu.uci.ics.crawler4j.crawler.CrawlController;
+import edu.uci.ics.crawler4j.fetcher.PageFetcher;
+import edu.uci.ics.crawler4j.robotstxt.RobotstxtConfig;
+import edu.uci.ics.crawler4j.robotstxt.RobotstxtServer;
+
+public class MultipleCrawlerController {
+    public static void main(String[] args) throws Exception {
+        File crawlStorageBase = new File("src/test/resources/crawler4j");
+        CrawlConfig htmlConfig = new CrawlConfig();
+        CrawlConfig imageConfig = new CrawlConfig();
+        
+        htmlConfig.setCrawlStorageFolder(new File(crawlStorageBase, "html").getAbsolutePath());
+        imageConfig.setCrawlStorageFolder(new File(crawlStorageBase, "image").getAbsolutePath());
+        imageConfig.setIncludeBinaryContentInCrawling(true);
+        
+        htmlConfig.setMaxPagesToFetch(500);
+        imageConfig.setMaxPagesToFetch(1000);
+        
+        PageFetcher pageFetcherHtml = new PageFetcher(htmlConfig);
+        PageFetcher pageFetcherImage = new PageFetcher(imageConfig);
+        
+        RobotstxtConfig robotstxtConfig = new RobotstxtConfig();
+        RobotstxtServer robotstxtServer = new RobotstxtServer(robotstxtConfig, pageFetcherHtml);
+
+        CrawlController htmlController = new CrawlController(htmlConfig, pageFetcherHtml, robotstxtServer);
+        CrawlController imageController = new CrawlController(imageConfig, pageFetcherImage, robotstxtServer);
+        
+        htmlController.addSeed("https://www.baeldung.com/");
+        imageController.addSeed("https://www.baeldung.com/");
+        
+        CrawlerStatistics stats = new CrawlerStatistics();
+        CrawlController.WebCrawlerFactory<HtmlCrawler> htmlFactory = () -> new HtmlCrawler(stats);
+        
+        File saveDir = new File("src/test/resources/crawler4j");
+        CrawlController.WebCrawlerFactory<ImageCrawler> imageFactory = () -> new ImageCrawler(saveDir);
+        
+        imageController.startNonBlocking(imageFactory, 7);
+        htmlController.startNonBlocking(htmlFactory, 10);
+        
+
+        htmlController.waitUntilFinish();
+        System.out.printf("Crawled %d pages %n", stats.getProcessedPageCount());
+        System.out.printf("Total Number of outbound links = %d %n", stats.getTotalLinksCount());
+
+        imageController.waitUntilFinish();
+        System.out.printf("Image Crawler is finished.");
+        
+    }
+}

libraries-2/src/main/java/com/baeldung/jbpm/WorkflowProcessMain.java

@@ -0,0 +1,19 @@
+package com.baeldung.jbpm;
+
+import org.kie.api.runtime.manager.Context;
+import org.kie.internal.runtime.manager.context.EmptyContext;
+
+import com.baeldung.jbpm.engine.WorkflowEngine;
+import com.baeldung.jbpm.engine.WorkflowEngineImpl;
+
+public class WorkflowProcessMain {
+
+    public static void main(String[] args) {
+        WorkflowEngine workflowEngine = new WorkflowEngineImpl();
+        String processId = "com.baeldung.bpmn.helloworld";
+        String kbaseId = "kbase";
+        String persistenceUnit = "org.jbpm.persistence.jpa";
+        Context<String> initialContext = EmptyContext.get();
+        workflowEngine.runjBPMEngineForProcess(processId, initialContext, kbaseId, persistenceUnit);
+    }
+}

libraries-2/src/main/java/com/baeldung/jbpm/engine/WorkflowEngine.java

@@ -0,0 +1,10 @@
+package com.baeldung.jbpm.engine;
+
+import org.kie.api.runtime.manager.Context;
+import org.kie.api.runtime.process.ProcessInstance;
+
+public interface WorkflowEngine {
+   
+    public ProcessInstance runjBPMEngineForProcess(String processId, Context<String> initialContext, String kbaseId, String persistenceUnit);
+    
+}

libraries-2/src/main/java/com/baeldung/jbpm/engine/WorkflowEngineImpl.java

@@ -0,0 +1,66 @@
+package com.baeldung.jbpm.engine;
+
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.Persistence;
+
+import org.jbpm.test.JBPMHelper;
+import org.kie.api.KieBase;
+import org.kie.api.KieServices;
+import org.kie.api.runtime.KieContainer;
+import org.kie.api.runtime.KieSession;
+import org.kie.api.runtime.manager.Context;
+import org.kie.api.runtime.manager.RuntimeEngine;
+import org.kie.api.runtime.manager.RuntimeEnvironment;
+import org.kie.api.runtime.manager.RuntimeEnvironmentBuilder;
+import org.kie.api.runtime.manager.RuntimeManager;
+import org.kie.api.runtime.manager.RuntimeManagerFactory;
+import org.kie.api.runtime.process.ProcessInstance;
+
+public class WorkflowEngineImpl implements WorkflowEngine {
+
+    @Override
+    public ProcessInstance runjBPMEngineForProcess(String processId, Context<String> initialContext, String kbaseId, String persistenceUnit) {
+        RuntimeManager manager = null;
+        RuntimeEngine engine = null;
+        ProcessInstance pInstance = null;
+        try {
+            KieBase kbase = getKieBase(kbaseId);
+            manager = createJBPMRuntimeManager(kbase, persistenceUnit);
+            engine = manager.getRuntimeEngine(initialContext);
+            pInstance = executeProcessInstance(processId, manager, initialContext, engine);
+        } catch (Exception ex) {
+            ex.printStackTrace();
+        } finally {
+            if (manager != null && engine != null)
+                manager.disposeRuntimeEngine(engine);
+            System.exit(0);
+        }
+        return pInstance;
+    }
+
+    private ProcessInstance executeProcessInstance(String processId, RuntimeManager manager, Context<String> initialContext, RuntimeEngine engine) {
+        KieSession ksession = engine.getKieSession();
+        ProcessInstance pInstance = ksession.startProcess(processId);
+        return pInstance;
+    }
+
+    private KieBase getKieBase(String kbaseId) {
+        KieServices ks = KieServices.Factory.get();
+        KieContainer kContainer = ks.getKieClasspathContainer();
+        KieBase kbase = kContainer.getKieBase(kbaseId);
+        return kbase;
+    }
+
+    private RuntimeManager createJBPMRuntimeManager(KieBase kbase, String persistenceUnit) {
+        JBPMHelper.startH2Server();
+        JBPMHelper.setupDataSource();
+        EntityManagerFactory emf = Persistence.createEntityManagerFactory(persistenceUnit);
+        RuntimeEnvironmentBuilder runtimeEnvironmentBuilder = RuntimeEnvironmentBuilder.Factory.get()
+            .newDefaultBuilder();
+        RuntimeEnvironment runtimeEnvironment = runtimeEnvironmentBuilder.entityManagerFactory(emf)
+            .knowledgeBase(kbase)
+            .get();
+        return RuntimeManagerFactory.Factory.get()
+            .newSingletonRuntimeManager(runtimeEnvironment);
+    }
+}

libraries-2/src/main/java/com/baeldung/mesos/HelloWorldMain.java

@@ -0,0 +1,42 @@
+package com.baeldung.mesos;
+
+import com.baeldung.mesos.schedulers.HelloWorldScheduler;
+import org.apache.mesos.MesosSchedulerDriver;
+import org.apache.mesos.Protos;
+import org.apache.mesos.Protos.CommandInfo;
+import org.apache.mesos.Protos.ExecutorInfo;
+import org.apache.mesos.Protos.FrameworkInfo;
+
+public class HelloWorldMain {
+
+    public static void main(String[] args) {
+
+        String path = System.getProperty("user.dir")
+                + "/target/libraries2-1.0.0-SNAPSHOT.jar";
+
+        CommandInfo.URI uri = CommandInfo.URI.newBuilder().setValue(path).setExtract(false).build();
+
+        String helloWorldCommand = "java -cp libraries2-1.0.0-SNAPSHOT.jar com.baeldung.mesos.executors.HelloWorldExecutor";
+        CommandInfo commandInfoHelloWorld = CommandInfo.newBuilder().setValue(helloWorldCommand).addUris(uri)
+                .build();
+
+        ExecutorInfo executorHelloWorld = ExecutorInfo.newBuilder()
+                .setExecutorId(Protos.ExecutorID.newBuilder().setValue("HelloWorldExecutor"))
+                .setCommand(commandInfoHelloWorld).setName("Hello World (Java)").setSource("java").build();
+
+        FrameworkInfo.Builder frameworkBuilder = FrameworkInfo.newBuilder().setFailoverTimeout(120000)
+                .setUser("")
+                .setName("Hello World Framework (Java)");
+
+        frameworkBuilder.setPrincipal("test-framework-java");
+
+        MesosSchedulerDriver driver = new MesosSchedulerDriver(new HelloWorldScheduler(executorHelloWorld), frameworkBuilder.build(), args[0]);
+
+        int status = driver.run() == Protos.Status.DRIVER_STOPPED ? 0 : 1;
+
+        // Ensure that the driver process terminates.
+        driver.stop();
+
+        System.exit(status);
+    }
+}

libraries-2/src/main/java/com/baeldung/mesos/executors/HelloWorldExecutor.java

@@ -0,0 +1,59 @@
+package com.baeldung.mesos.executors;
+
+import org.apache.mesos.Executor;
+import org.apache.mesos.ExecutorDriver;
+import org.apache.mesos.MesosExecutorDriver;
+import org.apache.mesos.Protos;
+import org.apache.mesos.Protos.TaskInfo;
+
+public class HelloWorldExecutor implements Executor {
+    @Override
+    public void registered(ExecutorDriver driver, Protos.ExecutorInfo executorInfo, Protos.FrameworkInfo frameworkInfo, Protos.SlaveInfo slaveInfo) {
+    }
+
+    @Override
+    public void reregistered(ExecutorDriver driver, Protos.SlaveInfo slaveInfo) {
+    }
+
+    @Override
+    public void disconnected(ExecutorDriver driver) {
+    }
+
+    @Override
+    public void launchTask(ExecutorDriver driver, TaskInfo task) {
+
+        Protos.TaskStatus status = Protos.TaskStatus.newBuilder().setTaskId(task.getTaskId())
+                .setState(Protos.TaskState.TASK_RUNNING).build();
+        driver.sendStatusUpdate(status);
+
+        String myStatus = "Hello Framework";
+        driver.sendFrameworkMessage(myStatus.getBytes());
+
+        System.out.println("Hello World!!!");
+
+        status = Protos.TaskStatus.newBuilder().setTaskId(task.getTaskId())
+                .setState(Protos.TaskState.TASK_FINISHED).build();
+        driver.sendStatusUpdate(status);
+    }
+
+    @Override
+    public void killTask(ExecutorDriver driver, Protos.TaskID taskId) {
+    }
+
+    @Override
+    public void frameworkMessage(ExecutorDriver driver, byte[] data) {
+    }
+
+    @Override
+    public void shutdown(ExecutorDriver driver) {
+    }
+
+    @Override
+    public void error(ExecutorDriver driver, String message) {
+    }
+
+    public static void main(String[] args) {
+        MesosExecutorDriver driver = new MesosExecutorDriver(new HelloWorldExecutor());
+        System.exit(driver.run() == Protos.Status.DRIVER_STOPPED ? 0 : 1);
+    }
+}

libraries-2/src/main/java/com/baeldung/mesos/schedulers/HelloWorldScheduler.java

@@ -0,0 +1,100 @@
+package com.baeldung.mesos.schedulers;
+
+import com.google.protobuf.ByteString;
+import org.apache.mesos.Protos;
+import org.apache.mesos.Protos.ExecutorInfo;
+import org.apache.mesos.Protos.Offer;
+import org.apache.mesos.Protos.OfferID;
+import org.apache.mesos.Protos.TaskInfo;
+import org.apache.mesos.Scheduler;
+import org.apache.mesos.SchedulerDriver;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class HelloWorldScheduler implements Scheduler {
+
+    private int launchedTasks = 0;
+    private final ExecutorInfo helloWorldExecutor;
+
+    public HelloWorldScheduler(ExecutorInfo helloWorldExecutor) {
+        this.helloWorldExecutor = helloWorldExecutor;
+    }
+
+    @Override
+    public void registered(SchedulerDriver schedulerDriver, Protos.FrameworkID frameworkID, Protos.MasterInfo masterInfo) {
+
+    }
+
+    @Override
+    public void reregistered(SchedulerDriver schedulerDriver, Protos.MasterInfo masterInfo) {
+
+    }
+
+    @Override
+    public void resourceOffers(SchedulerDriver schedulerDriver, List<Offer> list) {
+
+        for (Offer offer : list) {
+            List<TaskInfo> tasks = new ArrayList<TaskInfo>();
+            Protos.TaskID taskId = Protos.TaskID.newBuilder().setValue(Integer.toString(launchedTasks++)).build();
+
+            System.out.println("Launching printHelloWorld " + taskId.getValue() + " Hello World Java");
+            TaskInfo printHelloWorld = TaskInfo
+                    .newBuilder()
+                    .setName("printHelloWorld " + taskId.getValue())
+                    .setTaskId(taskId)
+                    .setSlaveId(offer.getSlaveId())
+                    .addResources(
+                            Protos.Resource.newBuilder().setName("cpus").setType(Protos.Value.Type.SCALAR)
+                                    .setScalar(Protos.Value.Scalar.newBuilder().setValue(1)))
+                    .addResources(
+                            Protos.Resource.newBuilder().setName("mem").setType(Protos.Value.Type.SCALAR)
+                                    .setScalar(Protos.Value.Scalar.newBuilder().setValue(128)))
+                    .setExecutor(ExecutorInfo.newBuilder(helloWorldExecutor)).build();
+
+            List<OfferID> offerIDS = new ArrayList<>();
+            offerIDS.add(offer.getId());
+
+            tasks.add(printHelloWorld);
+
+            schedulerDriver.declineOffer(offer.getId());
+            schedulerDriver.launchTasks(offerIDS, tasks);
+        }
+
+    }
+
+    @Override
+    public void offerRescinded(SchedulerDriver schedulerDriver, OfferID offerID) {
+
+    }
+
+    @Override
+    public void statusUpdate(SchedulerDriver schedulerDriver, Protos.TaskStatus taskStatus) {
+
+    }
+
+    @Override
+    public void frameworkMessage(SchedulerDriver schedulerDriver, Protos.ExecutorID executorID, Protos.SlaveID slaveID, byte[] bytes) {
+
+    }
+
+    @Override
+    public void disconnected(SchedulerDriver schedulerDriver) {
+
+    }
+
+    @Override
+    public void slaveLost(SchedulerDriver schedulerDriver, Protos.SlaveID slaveID) {
+
+    }
+
+    @Override
+    public void executorLost(SchedulerDriver schedulerDriver, Protos.ExecutorID executorID, Protos.SlaveID slaveID, int i) {
+
+    }
+
+    @Override
+    public void error(SchedulerDriver schedulerDriver, String s) {
+
+    }
+}

libraries-2/src/main/java/com/baeldung/picocli/git/Application.java

@@ -0,0 +1,41 @@
+package com.baeldung.picocli.git;
+
+import com.baeldung.picocli.git.commands.programmative.GitCommand;
+import com.baeldung.picocli.git.commands.subcommands.GitAddCommand;
+import com.baeldung.picocli.git.commands.subcommands.GitCommitCommand;
+import com.baeldung.picocli.git.commands.subcommands.GitConfigCommand;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import picocli.CommandLine;
+
+@SpringBootApplication
+public class Application implements CommandLineRunner {
+    public static void main(String[] args) {
+        SpringApplication.run(Application.class, args);
+    }
+
+    private GitCommand gitCommand;
+    private GitAddCommand addCommand;
+    private GitCommitCommand commitCommand;
+    private GitConfigCommand configCommand;
+
+    @Autowired
+    public Application(GitCommand gitCommand, GitAddCommand addCommand, GitCommitCommand commitCommand, GitConfigCommand configCommand) {
+        this.gitCommand = gitCommand;
+        this.addCommand = addCommand;
+        this.commitCommand = commitCommand;
+        this.configCommand = configCommand;
+    }
+
+    @Override
+    public void run(String... args) {
+        CommandLine commandLine = new CommandLine(gitCommand);
+        commandLine.addSubcommand("add", addCommand);
+        commandLine.addSubcommand("commit", commitCommand);
+        commandLine.addSubcommand("config", configCommand);
+
+        commandLine.parseWithHandler(new CommandLine.RunLast(), args);
+    }
+}

libraries-2/src/main/java/com/baeldung/picocli/git/commands/declarative/GitCommand.java

@@ -0,0 +1,32 @@
+package com.baeldung.picocli.git.commands.declarative;
+
+import com.baeldung.picocli.git.model.ConfigElement;
+import com.baeldung.picocli.git.commands.subcommands.GitAddCommand;
+import com.baeldung.picocli.git.commands.subcommands.GitCommitCommand;
+import com.baeldung.picocli.git.commands.subcommands.GitConfigCommand;
+import picocli.CommandLine;
+
+import static picocli.CommandLine.*;
+import static picocli.CommandLine.Command;
+
+@Command(
+  name = "git",
+  subcommands = {
+    GitAddCommand.class,
+    GitCommitCommand.class,
+    GitConfigCommand.class
+  }
+)
+public class GitCommand implements Runnable {
+    public static void main(String[] args) {
+        CommandLine commandLine = new CommandLine(new GitCommand());
+        commandLine.registerConverter(ConfigElement.class, ConfigElement::from);
+
+        commandLine.parseWithHandler(new RunLast(), args);
+    }
+
+    @Override
+    public void run() {
+        System.out.println("The popular git command");
+    }
+}

libraries-2/src/main/java/com/baeldung/picocli/git/commands/methods/GitCommand.java

@@ -0,0 +1,27 @@
+package com.baeldung.picocli.git.commands.methods;
+
+import picocli.CommandLine;
+
+import static picocli.CommandLine.Command;
+
+@Command(name = "git")
+public class GitCommand implements Runnable {
+    public static void main(String[] args) {
+        CommandLine.run(new GitCommand(), args);
+    }
+
+    @Override
+    public void run() {
+        System.out.println("The popular git command");
+    }
+
+    @Command(name = "add")
+    public void addCommand() {
+        System.out.println("Adding some files to the staging area");
+    }
+
+    @Command(name = "commit")
+    public void commitCommand() {
+        System.out.println("Committing files in the staging area, how wonderful?");
+    }
+}

libraries-2/src/main/java/com/baeldung/picocli/git/commands/programmative/GitCommand.java

@@ -0,0 +1,26 @@
+package com.baeldung.picocli.git.commands.programmative;
+
+import com.baeldung.picocli.git.commands.subcommands.GitAddCommand;
+import com.baeldung.picocli.git.commands.subcommands.GitCommitCommand;
+import org.springframework.stereotype.Component;
+import picocli.CommandLine;
+
+import static picocli.CommandLine.Command;
+import static picocli.CommandLine.RunLast;
+
+@Command(name = "git")
+@Component
+public class GitCommand implements Runnable {
+    public static void main(String[] args) {
+        CommandLine commandLine = new CommandLine(new GitCommand());
+        commandLine.addSubcommand("add", new GitAddCommand());
+        commandLine.addSubcommand("commit", new GitCommitCommand());
+
+        commandLine.parseWithHandler(new RunLast(), args);
+    }
+
+    @Override
+    public void run() {
+        System.out.println("The popular git command");
+    }
+}

libraries-2/src/main/java/com/baeldung/picocli/git/commands/subcommands/GitAddCommand.java

@@ -0,0 +1,31 @@
+package com.baeldung.picocli.git.commands.subcommands;
+
+import org.springframework.stereotype.Component;
+
+import java.nio.file.Path;
+import java.util.List;
+
+import static picocli.CommandLine.*;
+
+@Command(
+  name = "add"
+)
+@Component
+public class GitAddCommand implements Runnable {
+    @Option(names = "-A")
+    private boolean allFiles;
+
+    @Parameters(index = "0..*")
+    private List<Path> files;
+
+    @Override
+    public void run() {
+        if (allFiles) {
+            System.out.println("Adding all files to the staging area");
+        }
+
+        if (files != null) {
+            files.forEach(path -> System.out.println("Adding " + path + " to the staging area"));
+        }
+    }
+}

libraries-2/src/main/java/com/baeldung/picocli/git/commands/subcommands/GitCommitCommand.java

@@ -0,0 +1,26 @@
+package com.baeldung.picocli.git.commands.subcommands;
+
+import org.springframework.stereotype.Component;
+
+import static picocli.CommandLine.Command;
+import static picocli.CommandLine.Option;
+
+@Command(
+  name = "commit"
+)
+@Component
+public class GitCommitCommand implements Runnable {
+    @Option(names = {"-m", "--message"}, required = true)
+    private String[] messages;
+
+    @Override
+    public void run() {
+        System.out.println("Committing files in the staging area, how wonderful?");
+        if (messages != null) {
+            System.out.println("The commit message is");
+            for (String message : messages) {
+                System.out.println(message);
+            }
+        }
+    }
+}

libraries-2/src/main/java/com/baeldung/picocli/git/commands/subcommands/GitConfigCommand.java

@@ -0,0 +1,24 @@
+package com.baeldung.picocli.git.commands.subcommands;
+
+import com.baeldung.picocli.git.model.ConfigElement;
+import org.springframework.stereotype.Component;
+
+import static picocli.CommandLine.Command;
+import static picocli.CommandLine.Parameters;
+
+@Command(
+  name = "config"
+)
+@Component
+public class GitConfigCommand implements Runnable {
+    @Parameters(index = "0")
+    private ConfigElement element;
+
+    @Parameters(index = "1")
+    private String value;
+
+    @Override
+    public void run() {
+        System.out.println("Setting " + element.value() + " to " + value);
+    }
+}

libraries-2/src/main/java/com/baeldung/picocli/git/model/ConfigElement.java

@@ -0,0 +1,25 @@
+package com.baeldung.picocli.git.model;
+
+import java.util.Arrays;
+
+public enum ConfigElement {
+    USERNAME("user.name"),
+    EMAIL("user.email");
+
+    private final String value;
+
+    ConfigElement(String value) {
+        this.value = value;
+    }
+
+    public String value() {
+        return value;
+    }
+
+    public static ConfigElement from(String value) {
+        return Arrays.stream(values())
+          .filter(element -> element.value.equals(value))
+          .findFirst()
+          .orElseThrow(() -> new IllegalArgumentException("The argument " + value + " doesn't match any ConfigElement"));
+    }
+}

libraries-2/src/main/java/com/baeldung/picocli/helloworld/HelloWorldCommand.java

@@ -0,0 +1,20 @@
+package com.baeldung.picocli.helloworld;
+
+import picocli.CommandLine;
+
+import static picocli.CommandLine.Command;
+
+@Command(
+  name = "hello",
+  description = "Says hello"
+)
+public class HelloWorldCommand implements Runnable {
+    public static void main(String[] args) {
+        CommandLine.run(new HelloWorldCommand(), args);
+    }
+
+    @Override
+    public void run() {
+        System.out.println("Hello World!");
+    }
+}

libraries-2/src/main/resources/META-INF/kmodule.xml

@@ -0,0 +1,3 @@
+<kmodule xmlns="http://jboss.org/kie/6.0.0/kmodule">
+	<kbase name="kbase" packages="com.baeldung.process" />
+</kmodule>

libraries-2/src/main/resources/com/baeldung/process/helloworld.bpmn

@@ -0,0 +1,54 @@
+<?xml version="1.0" encoding="UTF-8"?> 
+<definitions id="Definition"
+             targetNamespace="http://www.jboss.org/drools"
+             typeLanguage="http://www.java.com/javaTypes"
+             expressionLanguage="http://www.mvel.org/2.0"
+             xmlns="http://www.omg.org/spec/BPMN/20100524/MODEL"
+             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+             xsi:schemaLocation="http://www.omg.org/spec/BPMN/20100524/MODEL BPMN20.xsd"
+             xmlns:g="http://www.jboss.org/drools/flow/gpd"
+             xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI"
+             xmlns:dc="http://www.omg.org/spec/DD/20100524/DC"
+             xmlns:di="http://www.omg.org/spec/DD/20100524/DI"
+             xmlns:tns="http://www.jboss.org/drools">
+
+  <process processType="Private" isExecutable="true" id="com.baeldung.bpmn.helloworld" name="HelloWorld Process" tns:packageName="com.baeldung.bpmn.process" >
+
+    <!-- nodes -->
+    <scriptTask id="_jbpm-unique-1" name="HelloWorld" scriptFormat="http://www.java.com/java" >
+      <script>System.out.println("Hello World");</script>
+    </scriptTask>
+    <endEvent id="_jbpm-unique-2" name="End" >
+        <terminateEventDefinition />
+    </endEvent>
+    <startEvent id="_jbpm-unique-0" name="Start"  isInterrupting="false"/>
+
+    <!-- connections -->
+    <sequenceFlow id="_jbpm-unique-0-_jbpm-unique-1" sourceRef="_jbpm-unique-0" targetRef="_jbpm-unique-1" />
+    <sequenceFlow id="_jbpm-unique-1-_jbpm-unique-2" sourceRef="_jbpm-unique-1" targetRef="_jbpm-unique-2" />
+
+  </process>
+
+  <bpmndi:BPMNDiagram>
+    <bpmndi:BPMNPlane bpmnElement="com.baeldung.bpmn.helloworld" >
+      <bpmndi:BPMNShape bpmnElement="_jbpm-unique-1" >
+        <dc:Bounds x="119" y="44" width="111" height="48" />
+      </bpmndi:BPMNShape>
+      <bpmndi:BPMNShape bpmnElement="_jbpm-unique-2" >
+        <dc:Bounds x="272" y="43" width="48" height="48" />
+      </bpmndi:BPMNShape>
+      <bpmndi:BPMNShape bpmnElement="_jbpm-unique-0" >
+        <dc:Bounds x="28" y="44" width="48" height="48" />
+      </bpmndi:BPMNShape>
+      <bpmndi:BPMNEdge bpmnElement="_jbpm-unique-0-_jbpm-unique-1" >
+        <di:waypoint x="52" y="68" />
+        <di:waypoint x="174" y="68" />
+      </bpmndi:BPMNEdge>
+      <bpmndi:BPMNEdge bpmnElement="_jbpm-unique-1-_jbpm-unique-2" >
+        <di:waypoint x="174" y="68" />
+        <di:waypoint x="296" y="67" />
+      </bpmndi:BPMNEdge>
+    </bpmndi:BPMNPlane>
+  </bpmndi:BPMNDiagram>
+
+</definitions>

libraries-2/src/test/java/com/baeldung/chroniclemap/ChronicleMapUnitTest.java

@@ -0,0 +1,132 @@
+package com.baeldung.chroniclemap;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+import java.io.File;
+import java.util.HashSet;
+import java.util.Set;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import net.openhft.chronicle.core.values.LongValue;
+import net.openhft.chronicle.map.ChronicleMap;
+import net.openhft.chronicle.map.ExternalMapQueryContext;
+import net.openhft.chronicle.map.MapEntry;
+import net.openhft.chronicle.values.Values;
+
+public class ChronicleMapUnitTest {
+
+    static ChronicleMap<LongValue, CharSequence> persistedCountryMap = null;
+
+    static ChronicleMap<LongValue, CharSequence> inMemoryCountryMap = null;
+
+    static ChronicleMap<Integer, Set<Integer>> multiMap = null;
+
+    @SuppressWarnings({ "unchecked", "rawtypes" })
+    @BeforeClass
+    public static void init() {
+        try {
+            inMemoryCountryMap = ChronicleMap.of(LongValue.class, CharSequence.class)
+                .name("country-map")
+                .entries(50)
+                .averageValue("America")
+                .create();
+
+            persistedCountryMap = ChronicleMap.of(LongValue.class, CharSequence.class)
+                .name("country-map")
+                .entries(50)
+                .averageValue("America")
+                .createPersistedTo(new File(System.getProperty("user.home") + "/country-details.dat"));
+
+            Set<Integer> averageValue = IntStream.of(1, 2)
+                .boxed()
+                .collect(Collectors.toSet());
+            multiMap = ChronicleMap.of(Integer.class, (Class<Set<Integer>>) (Class) Set.class)
+                .name("multi-map")
+                .entries(50)
+                .averageValue(averageValue)
+                .create();
+
+            LongValue qatarKey = Values.newHeapInstance(LongValue.class);
+            qatarKey.setValue(1);
+            inMemoryCountryMap.put(qatarKey, "Qatar");
+
+            LongValue key = Values.newHeapInstance(LongValue.class);
+            key.setValue(1);
+            persistedCountryMap.put(key, "Romania");
+            key.setValue(2);
+            persistedCountryMap.put(key, "India");
+
+            Set<Integer> set1 = new HashSet<>();
+            set1.add(1);
+            set1.add(2);
+            multiMap.put(1, set1);
+
+            Set<Integer> set2 = new HashSet<>();
+            set2.add(3);
+            multiMap.put(2, set2);
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+
+    @Test
+    public void givenGetQuery_whenCalled_shouldReturnResult() {
+        LongValue key = Values.newHeapInstance(LongValue.class);
+        key.setValue(1);
+        CharSequence country = inMemoryCountryMap.get(key);
+        assertThat(country.toString(), is(equalTo("Qatar")));
+    }
+
+    @Test
+    public void givenGetUsingQuery_whenCalled_shouldReturnResult() {
+        LongValue key = Values.newHeapInstance(LongValue.class);
+        StringBuilder country = new StringBuilder();
+        key.setValue(1);
+        persistedCountryMap.getUsing(key, country);
+        assertThat(country.toString(), is(equalTo("Romania")));
+        key.setValue(2);
+        persistedCountryMap.getUsing(key, country);
+        assertThat(country.toString(), is(equalTo("India")));
+    }
+
+    @Test
+    public void  givenMultipleKeyQuery_whenProcessed_shouldChangeTheValue() {
+        try (ExternalMapQueryContext<Integer, Set<Integer>, ?> fistContext = multiMap.queryContext(1)) {
+            try (ExternalMapQueryContext<Integer, Set<Integer>, ?> secondContext = multiMap.queryContext(2)) {
+                fistContext.updateLock()
+                    .lock();
+                secondContext.updateLock()
+                    .lock();
+                MapEntry<Integer, Set<Integer>> firstEntry = fistContext.entry();
+                Set<Integer> firstSet = firstEntry.value()
+                    .get();
+                firstSet.remove(2);
+                MapEntry<Integer, Set<Integer>> secondEntry = secondContext.entry();
+                Set<Integer> secondSet = secondEntry.value()
+                    .get();
+                secondSet.add(4);
+                firstEntry.doReplaceValue(fistContext.wrapValueAsData(firstSet));
+                secondEntry.doReplaceValue(secondContext.wrapValueAsData(secondSet));
+            }
+        } finally {
+            assertThat(multiMap.get(1)
+                .size(), is(equalTo(1)));
+            assertThat(multiMap.get(2)
+                .size(), is(equalTo(2)));
+        }
+    }
+
+    @AfterClass
+    public static void finish() {
+        persistedCountryMap.close();
+        inMemoryCountryMap.close();
+        multiMap.close();
+    }
+}

libraries-2/src/test/java/com/baeldung/classgraph/ClassGraphUnitTest.java

@@ -0,0 +1,74 @@
+package com.baeldung.classgraph;
+
+import io.github.classgraph.*;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.util.function.Consumer;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class ClassGraphUnitTest {
+
+    @Test
+    public void whenClassAnnotationFilterIsDefined_thenTargetClassesCanBeFound() {
+        doTest(result -> {
+            ClassInfoList classInfos = result.getClassesWithAnnotation(TestAnnotation.class.getName());
+            assertThat(classInfos).extracting(ClassInfo::getName).contains(ClassWithAnnotation.class.getName());
+        });
+    }
+
+    @Test
+    public void whenMethodAnnotationFilterIsDefined_thenTargetClassesCanBeFound() {
+        doTest(result -> {
+            ClassInfoList classInfos = result.getClassesWithMethodAnnotation(TestAnnotation.class.getName());
+            assertThat(classInfos).extracting(ClassInfo::getName).contains(MethodWithAnnotation.class.getName());
+        });
+    }
+
+    @Test
+    public void whenMethodAnnotationValueFilterIsDefined_thenTargetClassesCanBeFound() {
+        doTest(result -> {
+            ClassInfoList classInfos = result.getClassesWithMethodAnnotation(TestAnnotation.class.getName());
+            ClassInfoList filteredClassInfos = classInfos.filter(classInfo -> {
+                return classInfo.getMethodInfo().stream().anyMatch(methodInfo -> {
+                    AnnotationInfo annotationInfo = methodInfo.getAnnotationInfo(TestAnnotation.class.getName());
+                    if (annotationInfo == null) {
+                        return false;
+                    }
+
+                    return "web".equals(annotationInfo.getParameterValues().getValue("value"));
+                });
+            });
+            assertThat(filteredClassInfos)
+                    .extracting(ClassInfo::getName)
+                    .contains(MethodWithAnnotationParameterWeb.class.getName());
+        });
+    }
+
+    @Test
+    public void whenFieldAnnotationFilterIsDefined_thenTargetClassesCanBeFound() {
+        doTest(result -> {
+            ClassInfoList classInfos = result.getClassesWithFieldAnnotation(TestAnnotation.class.getName());
+            assertThat(classInfos).extracting(ClassInfo::getName).contains(FieldWithAnnotation.class.getName());
+        });
+    }
+
+    @Test
+    public void whenResourceIsUsed_thenItCanBeFoundAndLoaded() throws IOException {
+        try (ScanResult result = new ClassGraph().whitelistPaths("classgraph").scan()) {
+            ResourceList resources = result.getResourcesWithExtension("config");
+            assertThat(resources).extracting(Resource::getPath).containsOnly("classgraph/my.config");
+            assertThat(resources.get(0).getContentAsString()).isEqualTo("my data");
+        }
+    }
+
+    private void doTest(Consumer<ScanResult> checker) {
+        try (ScanResult result = new ClassGraph().enableAllInfo()
+                                                 .whitelistPackages(getClass().getPackage().getName())
+                                                 .scan())
+        {
+            checker.accept(result);
+        }
+    }
+}

libraries-2/src/test/java/com/baeldung/classgraph/ClassWithAnnotation.java

@@ -0,0 +1,5 @@
+package com.baeldung.classgraph;
+
+@TestAnnotation
+public class ClassWithAnnotation {
+}

libraries-2/src/test/java/com/baeldung/classgraph/FieldWithAnnotation.java

@@ -0,0 +1,7 @@
+package com.baeldung.classgraph;
+
+public class FieldWithAnnotation {
+
+    @TestAnnotation
+    private String s;
+}

libraries-2/src/test/java/com/baeldung/classgraph/MethodWithAnnotation.java

@@ -0,0 +1,8 @@
+package com.baeldung.classgraph;
+
+public class MethodWithAnnotation {
+
+    @TestAnnotation
+    public void service() {
+    }
+}

libraries-2/src/test/java/com/baeldung/classgraph/MethodWithAnnotationParameterDao.java

@@ -0,0 +1,8 @@
+package com.baeldung.classgraph;
+
+public class MethodWithAnnotationParameterDao {
+
+    @TestAnnotation("dao")
+    public void service() {
+    }
+}

libraries-2/src/test/java/com/baeldung/classgraph/MethodWithAnnotationParameterWeb.java

@@ -0,0 +1,8 @@
+package com.baeldung.classgraph;
+
+public class MethodWithAnnotationParameterWeb {
+
+    @TestAnnotation("web")
+    public void service() {
+    }
+}

libraries-2/src/test/java/com/baeldung/classgraph/TestAnnotation.java

@@ -0,0 +1,14 @@
+package com.baeldung.classgraph;
+
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+import static java.lang.annotation.ElementType.*;
+
+@Target({TYPE, METHOD, FIELD})
+@Retention(RetentionPolicy.RUNTIME)
+public @interface TestAnnotation {
+
+    String value() default "";
+}

libraries-2/src/test/java/com/baeldung/handlebars/BasicUsageUnitTest.java

@@ -0,0 +1,109 @@
+package com.baeldung.handlebars;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.github.jknack.handlebars.Handlebars;
+import com.github.jknack.handlebars.Template;
+import com.github.jknack.handlebars.io.ClassPathTemplateLoader;
+import com.github.jknack.handlebars.io.TemplateLoader;
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+import org.junit.Test;
+
+/**
+ * Showcases the tag usage and different template loading mechanisms.
+ *
+ * @author isaolmez
+ */
+public class BasicUsageUnitTest {
+
+    @Test
+    public void whenThereIsNoTemplateFile_ThenCompilesInline() throws IOException {
+        Handlebars handlebars = new Handlebars();
+        Template template = handlebars.compileInline("Hi {{this}}!");
+
+        String templateString = template.apply("Baeldung");
+
+        assertThat(templateString).isEqualTo("Hi Baeldung!");
+    }
+
+    @Test
+    public void whenParameterMapIsSupplied_thenDisplays() throws IOException {
+        Handlebars handlebars = new Handlebars();
+        Template template = handlebars.compileInline("Hi {{name}}!");
+        Map<String, String> parameterMap = new HashMap<>();
+        parameterMap.put("name", "Baeldung");
+
+        String templateString = template.apply(parameterMap);
+
+        assertThat(templateString).isEqualTo("Hi Baeldung!");
+    }
+
+    @Test
+    public void whenParameterObjectIsSupplied_ThenDisplays() throws IOException {
+        Handlebars handlebars = new Handlebars();
+        Template template = handlebars.compileInline("Hi {{name}}!");
+        Person person = new Person();
+        person.setName("Baeldung");
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("Hi Baeldung!");
+    }
+
+    @Test
+    public void whenMultipleParametersAreSupplied_ThenDisplays() throws IOException {
+        Handlebars handlebars = new Handlebars();
+        Template template = handlebars.compileInline("Hi {{name}}! This is {{topic}}.");
+        Map<String, String> parameterMap = new HashMap<>();
+        parameterMap.put("name", "Baeldung");
+        parameterMap.put("topic", "Handlebars");
+
+        String templateString = template.apply(parameterMap);
+
+        assertThat(templateString).isEqualTo("Hi Baeldung! This is Handlebars.");
+    }
+
+    @Test
+    public void whenNoLoaderIsGiven_ThenSearchesClasspath() throws IOException {
+        Handlebars handlebars = new Handlebars();
+        Template template = handlebars.compile("greeting");
+        Person person = getPerson("Baeldung");
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("Hi Baeldung!");
+    }
+
+    @Test
+    public void whenClasspathTemplateLoaderIsGiven_ThenSearchesClasspathWithPrefixSuffix() throws IOException {
+        TemplateLoader loader = new ClassPathTemplateLoader("/handlebars", ".html");
+        Handlebars handlebars = new Handlebars(loader);
+        Template template = handlebars.compile("greeting");
+        Person person = getPerson("Baeldung");
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("Hi Baeldung!");
+    }
+
+    @Test
+    public void whenMultipleLoadersAreGiven_ThenSearchesSequentially() throws IOException {
+        TemplateLoader firstLoader = new ClassPathTemplateLoader("/handlebars", ".html");
+        TemplateLoader secondLoader = new ClassPathTemplateLoader("/templates", ".html");
+        Handlebars handlebars = new Handlebars().with(firstLoader, secondLoader);
+        Template template = handlebars.compile("greeting");
+        Person person = getPerson("Baeldung");
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("Hi Baeldung!");
+    }
+
+    private Person getPerson(String name) {
+        Person person = new Person();
+        person.setName(name);
+        return person;
+    }
+}

libraries-2/src/test/java/com/baeldung/handlebars/BuiltinHelperUnitTest.java

@@ -0,0 +1,106 @@
+package com.baeldung.handlebars;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.github.jknack.handlebars.Handlebars;
+import com.github.jknack.handlebars.Template;
+import com.github.jknack.handlebars.io.ClassPathTemplateLoader;
+import com.github.jknack.handlebars.io.TemplateLoader;
+import java.io.IOException;
+import org.junit.Test;
+
+/**
+ * Showcases the built-in template helpers.
+ *
+ * @author isaolmez
+ */
+public class BuiltinHelperUnitTest {
+
+    private TemplateLoader templateLoader = new ClassPathTemplateLoader("/handlebars", ".html");
+
+    @Test
+    public void whenUsedWith_ThenContextChanges() throws IOException {
+        Handlebars handlebars = new Handlebars(templateLoader);
+        Template template = handlebars.compile("with");
+        Person person = getPerson("Baeldung");
+        person.getAddress().setStreet("World");
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("\n<h4>I live in World</h4>\n");
+    }
+
+    @Test
+    public void whenUsedWithMustacheStyle_ThenContextChanges() throws IOException {
+        Handlebars handlebars = new Handlebars(templateLoader);
+        Template template = handlebars.compile("with_mustache");
+        Person person = getPerson("Baeldung");
+        person.getAddress().setStreet("World");
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("\n<h4>I live in World</h4>\n");
+    }
+
+    @Test
+    public void whenUsedEach_ThenIterates() throws IOException {
+        Handlebars handlebars = new Handlebars(templateLoader);
+        Template template = handlebars.compile("each");
+        Person person = getPerson("Baeldung");
+        Person friend1 = getPerson("Java");
+        Person friend2 = getPerson("Spring");
+        person.getFriends().add(friend1);
+        person.getFriends().add(friend2);
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("\n<span>Java is my friend.</span>\n"
+                                               + "\n<span>Spring is my friend.</span>\n");
+    }
+
+    @Test
+    public void whenUsedEachMustacheStyle_ThenIterates() throws IOException {
+        Handlebars handlebars = new Handlebars(templateLoader);
+        Template template = handlebars.compile("each_mustache");
+        Person person = getPerson("Baeldung");
+        Person friend1 = getPerson("Java");
+        Person friend2 = getPerson("Spring");
+        person.getFriends().add(friend1);
+        person.getFriends().add(friend2);
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("\n<span>Java is my friend.</span>\n"
+                                               + "\n<span>Spring is my friend.</span>\n");
+    }
+
+    @Test
+    public void whenUsedIf_ThenPutsCondition() throws IOException {
+        Handlebars handlebars = new Handlebars(templateLoader);
+        Template template = handlebars.compile("if");
+        Person person = getPerson("Baeldung");
+        person.setBusy(true);
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("\n<h4>Baeldung is busy.</h4>\n");
+    }
+
+    @Test
+    public void whenUsedIfMustacheStyle_ThenPutsCondition() throws IOException {
+        Handlebars handlebars = new Handlebars(templateLoader);
+        Template template = handlebars.compile("if_mustache");
+        Person person = getPerson("Baeldung");
+        person.setBusy(true);
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("\n<h4>Baeldung is busy.</h4>\n");
+    }
+
+    private Person getPerson(String name) {
+        Person person = new Person();
+        person.setName(name);
+        return person;
+    }
+}

libraries-2/src/test/java/com/baeldung/handlebars/CustomHelperUnitTest.java

@@ -0,0 +1,59 @@
+package com.baeldung.handlebars;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.github.jknack.handlebars.Handlebars;
+import com.github.jknack.handlebars.Helper;
+import com.github.jknack.handlebars.Options;
+import com.github.jknack.handlebars.Template;
+import com.github.jknack.handlebars.io.ClassPathTemplateLoader;
+import com.github.jknack.handlebars.io.TemplateLoader;
+import java.io.IOException;
+import org.junit.Test;
+
+/**
+ * Showcases implementing a custom template helper.
+ *
+ * @author isaolmez
+ */
+public class CustomHelperUnitTest {
+
+    private TemplateLoader templateLoader = new ClassPathTemplateLoader("/handlebars", ".html");
+
+    @Test
+    public void whenHelperIsCreated_ThenCanRegister() throws IOException {
+        Handlebars handlebars = new Handlebars(templateLoader);
+        handlebars.registerHelper("isBusy", new Helper<Person>() {
+            @Override
+            public Object apply(Person context, Options options) throws IOException {
+                String busyString = context.isBusy() ? "busy" : "available";
+                return context.getName() + " - " + busyString;
+            }
+        });
+        Template template = handlebars.compile("person");
+        Person person = getPerson("Baeldung");
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("Baeldung - busy");
+    }
+
+    @Test
+    public void whenHelperSourceIsCreated_ThenCanRegister() throws IOException {
+        Handlebars handlebars = new Handlebars(templateLoader);
+        handlebars.registerHelpers(new HelperSource());
+        Template template = handlebars.compile("person");
+        Person person = getPerson("Baeldung");
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("Baeldung - busy");
+    }
+
+    private Person getPerson(String name) {
+        Person person = new Person();
+        person.setName(name);
+        person.setBusy(true);
+        return person;
+    }
+}

libraries-2/src/test/java/com/baeldung/handlebars/HelperSource.java

@@ -0,0 +1,9 @@
+package com.baeldung.handlebars;
+
+public class HelperSource {
+
+    public String isBusy(Person context) {
+        String busyString = context.isBusy() ? "busy" : "available";
+        return context.getName() + " - " + busyString;
+    }
+}

libraries-2/src/test/java/com/baeldung/handlebars/Person.java

@@ -0,0 +1,58 @@
+package com.baeldung.handlebars;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class Person {
+
+    private String name;
+    private boolean busy;
+    private Address address = new Address();
+    private List<Person> friends = new ArrayList<>();
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public boolean isBusy() {
+        return busy;
+    }
+
+    public void setBusy(boolean busy) {
+        this.busy = busy;
+    }
+
+    public Address getAddress() {
+        return address;
+    }
+
+    public void setAddress(Address address) {
+        this.address = address;
+    }
+
+    public List<Person> getFriends() {
+        return friends;
+    }
+
+    public void setFriends(List<Person> friends) {
+        this.friends = friends;
+    }
+
+    public static class Address {
+
+        private String street;
+
+        public String getStreet() {
+            return street;
+        }
+
+        public void setStreet(String street) {
+            this.street = street;
+        }
+    }
+
+}

libraries-2/src/test/java/com/baeldung/handlebars/ReusingTemplatesUnitTest.java

@@ -0,0 +1,49 @@
+package com.baeldung.handlebars;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.github.jknack.handlebars.Handlebars;
+import com.github.jknack.handlebars.Template;
+import com.github.jknack.handlebars.io.ClassPathTemplateLoader;
+import com.github.jknack.handlebars.io.TemplateLoader;
+import java.io.IOException;
+import org.junit.Test;
+
+/**
+ * Showcases reusing the existing templates.
+ *
+ * @author isaolmez
+ */
+public class ReusingTemplatesUnitTest {
+
+    private TemplateLoader templateLoader = new ClassPathTemplateLoader("/handlebars", ".html");
+
+    @Test
+    public void whenOtherTemplateIsReferenced_ThenCanReuse() throws IOException {
+        Handlebars handlebars = new Handlebars(templateLoader);
+        Template template = handlebars.compile("page");
+        Person person = new Person();
+        person.setName("Baeldung");
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("<h4>Hi Baeldung!</h4>\n<p>This is the page Baeldung</p>");
+    }
+
+    @Test
+    public void whenBlockIsDefined_ThenCanOverrideWithPartial() throws IOException {
+        Handlebars handlebars = new Handlebars(templateLoader);
+        Template template = handlebars.compile("simplemessage");
+        Person person = new Person();
+        person.setName("Baeldung");
+
+        String templateString = template.apply(person);
+
+        assertThat(templateString).isEqualTo("\n<html>\n"
+                                               + "<body>\n"
+                                               + "\n  This is the intro\n\n"
+                                               + "\n  Hi there!\n\n"
+                                               + "</body>\n"
+                                               + "</html>");
+    }
+}

libraries-2/src/test/java/com/baeldung/jbpm/WorkflowEngineIntegrationTest.java

@@ -0,0 +1,52 @@
+package com.baeldung.jbpm;
+
+import org.jbpm.test.JbpmJUnitBaseTestCase;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.kie.api.runtime.KieSession;
+import org.kie.api.runtime.manager.RuntimeEngine;
+import org.kie.api.runtime.manager.RuntimeManager;
+import org.kie.api.runtime.process.ProcessInstance;
+import org.kie.internal.runtime.manager.context.ProcessInstanceIdContext;
+
+public class WorkflowEngineIntegrationTest extends JbpmJUnitBaseTestCase {
+
+    private String[] triggeredNodesArray = { "Start", "HelloWorld", "End" };
+    private RuntimeManager manager = null;
+    private RuntimeEngine runtimeEngine = null;
+    private KieSession ksession = null;
+    private ProcessInstance processInstance = null;
+
+    @Before
+    public void setup() {
+        manager = createRuntimeManager(Strategy.SINGLETON, "manager", "com/baeldung/process/helloworld.bpmn");
+        runtimeEngine = getRuntimeEngine(ProcessInstanceIdContext.get());
+        ksession = runtimeEngine.getKieSession();
+        processInstance = ksession.startProcess("com.baeldung.bpmn.helloworld");
+    }
+
+    @After
+    public void cleanup() {
+        manager.disposeRuntimeEngine(runtimeEngine);
+    }
+
+    @Test
+    public void givenProcessInstance_whenExecutionCompleted_thenVerifyNodesExecutionOrder() {
+        assertNodeTriggered(processInstance.getId(), triggeredNodesArray);
+    }
+
+    @Test
+    public void givenProcessInstance_whenExecutionCompleted_thenVerifyKnowledgeSessionId() {
+        int ksessionID = ksession.getId();
+        runtimeEngine = getRuntimeEngine(ProcessInstanceIdContext.get(processInstance.getId()));
+        ksession = runtimeEngine.getKieSession();
+        assertEquals(ksessionID, ksession.getId());
+    }
+
+    @Test
+    public void givenProcessInstance_whenExecutionCompleted_thenVerifyProcessInstanceStatus() {
+        assertProcessInstanceCompleted(processInstance.getId(), ksession);
+        assertTrue("ProcessInstance completed with status 2", processInstance.getState() == 2);
+    }
+}

libraries-2/src/test/java/com/baeldung/mapdb/CollectionsUnitTest.java

@@ -0,0 +1,33 @@
+package com.baeldung.mapdb;
+
+import org.junit.Test;
+import org.mapdb.DB;
+import org.mapdb.DBMaker;
+import org.mapdb.Serializer;
+
+import java.util.NavigableSet;
+
+import static junit.framework.Assert.assertEquals;
+
+public class CollectionsUnitTest {
+
+    @Test
+    public void givenSetCreatedInDB_whenMultipleElementsAdded_checkOnlyOneExists() {
+
+        DB db = DBMaker.memoryDB().make();
+
+        NavigableSet<String> set = db.
+          treeSet("mySet")
+          .serializer(Serializer.STRING)
+          .createOrOpen();
+
+        String myString = "Baeldung!";
+
+        set.add(myString);
+        set.add(myString);
+
+        assertEquals(1, set.size());
+
+        db.close();
+    }
+}

libraries-2/src/test/java/com/baeldung/mapdb/HTreeMapUnitTest.java

@@ -0,0 +1,38 @@
+package com.baeldung.mapdb;
+
+import org.jetbrains.annotations.NotNull;
+import org.junit.Test;
+import org.mapdb.*;
+
+import java.io.IOException;
+
+import static junit.framework.Assert.assertEquals;
+
+public class HTreeMapUnitTest {
+
+    @Test
+    public void givenValidDB_whenHTreeMapAddedToAndRetrieved_CheckedRetrievalCorrect() {
+
+        DB db = DBMaker.memoryDB().make();
+
+        HTreeMap<String, String> hTreeMap = db
+          .hashMap("myTreMap")
+          .keySerializer(Serializer.STRING)
+          .valueSerializer(Serializer.STRING)
+          .create();
+
+        hTreeMap.put("key1", "value1");
+        hTreeMap.put("key2", "value2");
+
+        assertEquals(2, hTreeMap.size());
+
+        //add another value with the same key
+
+        hTreeMap.put("key1", "value3");
+
+        assertEquals(2, hTreeMap.size());
+        assertEquals("value3", hTreeMap.get("key1"));
+
+    }
+
+}

libraries-2/src/test/java/com/baeldung/mapdb/HelloBaeldungUnitTest.java

@@ -0,0 +1,49 @@
+package com.baeldung.mapdb;
+
+import org.junit.Test;
+import org.mapdb.DB;
+import org.mapdb.DBMaker;
+import org.mapdb.HTreeMap;
+
+import java.util.concurrent.ConcurrentMap;
+
+import static junit.framework.Assert.assertEquals;
+
+public class HelloBaeldungUnitTest {
+
+    @Test
+    public void givenInMemoryDBInstantiateCorrectly_whenDataSavedAndRetrieved_checkRetrievalCorrect() {
+
+        DB db = DBMaker.memoryDB().make();
+
+        String welcomeMessageKey = "Welcome Message";
+        String welcomeMessageString = "Hello Baeldung!";
+
+        HTreeMap myMap = db.hashMap("myMap").createOrOpen();
+        myMap.put(welcomeMessageKey, welcomeMessageString);
+
+        String welcomeMessageFromDB = (String) myMap.get(welcomeMessageKey);
+
+        db.close();
+
+        assertEquals(welcomeMessageString, welcomeMessageFromDB);
+    }
+
+    @Test
+    public void givenInFileDBInstantiateCorrectly_whenDataSavedAndRetrieved_checkRetrievalCorrect() {
+
+        DB db = DBMaker.fileDB("file.db").make();
+
+        String welcomeMessageKey = "Welcome Message";
+        String welcomeMessageString = "Hello Baeldung!";
+
+        HTreeMap myMap = db.hashMap("myMap").createOrOpen();
+        myMap.put(welcomeMessageKey, welcomeMessageString);
+
+        String welcomeMessageFromDB = (String) myMap.get(welcomeMessageKey);
+
+        db.close();
+
+        assertEquals(welcomeMessageString, welcomeMessageFromDB);
+    }
+}

libraries-2/src/test/java/com/baeldung/mapdb/InMemoryModesUnitTest.java

@@ -0,0 +1,62 @@
+package com.baeldung.mapdb;
+
+import org.junit.Test;
+import org.mapdb.DB;
+import org.mapdb.DBMaker;
+import org.mapdb.HTreeMap;
+import org.mapdb.Serializer;
+
+import static junit.framework.Assert.assertEquals;
+
+public class InMemoryModesUnitTest {
+
+    @Test
+    public void givenDBCreatedOnHeap_whenUsed_checkUsageCorrect() {
+
+        DB heapDB = DBMaker.heapDB().make();
+
+        HTreeMap<Integer, String> map = heapDB
+          .hashMap("myMap")
+          .keySerializer(Serializer.INTEGER)
+          .valueSerializer(Serializer.STRING)
+          .createOrOpen();
+
+        map.put(1, "ONE");
+
+        assertEquals("ONE", map.get(1));
+
+    }
+
+    @Test
+    public void givenDBCreatedBaseOnByteArray_whenUsed_checkUsageCorrect() {
+
+        DB heapDB = DBMaker.memoryDB().make();
+
+        HTreeMap<Integer, String> map = heapDB
+          .hashMap("myMap")
+          .keySerializer(Serializer.INTEGER)
+          .valueSerializer(Serializer.STRING)
+          .createOrOpen();
+
+        map.put(1, "ONE");
+
+        assertEquals("ONE", map.get(1));
+    }
+
+    @Test
+    public void givenDBCreatedBaseOnDirectByteBuffer_whenUsed_checkUsageCorrect() {
+
+        DB heapDB = DBMaker.memoryDirectDB().make();
+
+        HTreeMap<Integer, String> map = heapDB
+          .hashMap("myMap")
+          .keySerializer(Serializer.INTEGER)
+          .valueSerializer(Serializer.STRING)
+          .createOrOpen();
+
+        map.put(1, "ONE");
+
+        assertEquals("ONE", map.get(1));
+    }
+
+}

libraries-2/src/test/java/com/baeldung/mapdb/SortedTableMapUnitTest.java

@@ -0,0 +1,47 @@
+package com.baeldung.mapdb;
+
+import org.junit.Test;
+import org.mapdb.Serializer;
+import org.mapdb.SortedTableMap;
+import org.mapdb.volume.MappedFileVol;
+import org.mapdb.volume.Volume;
+
+import static junit.framework.Assert.assertEquals;
+
+public class SortedTableMapUnitTest {
+
+    private static final String VOLUME_LOCATION = "sortedTableMapVol.db";
+
+    @Test
+    public void givenValidSortedTableMapSetup_whenQueried_checkValuesCorrect() {
+
+        //create memory mapped volume, readonly false
+        Volume vol = MappedFileVol.FACTORY.makeVolume(VOLUME_LOCATION, false);
+
+        //create sink to feed the map with data
+        SortedTableMap.Sink<Integer, String> sink =
+          SortedTableMap.create(
+            vol,
+            Serializer.INTEGER,
+            Serializer.STRING
+          ).createFromSink();
+
+        //add content
+        for(int i = 0; i < 100; i++){
+          sink.put(i, "Value " + Integer.toString(i));
+        }
+
+        sink.create();
+
+        //now open in read-only mode
+        Volume openVol = MappedFileVol.FACTORY.makeVolume(VOLUME_LOCATION, true);
+
+        SortedTableMap<Integer, String> sortedTableMap = SortedTableMap.open(
+          openVol,
+          Serializer.INTEGER,
+          Serializer.STRING
+        );
+
+        assertEquals(100, sortedTableMap.size());
+    }
+}

libraries-2/src/test/java/com/baeldung/mapdb/TransactionsUnitTest.java

@@ -0,0 +1,41 @@
+package com.baeldung.mapdb;
+
+import org.junit.Test;
+import org.mapdb.DB;
+import org.mapdb.DBMaker;
+import org.mapdb.Serializer;
+
+import java.util.NavigableSet;
+
+import static junit.framework.Assert.assertEquals;
+
+public class TransactionsUnitTest {
+
+    @Test
+    public void givenValidDBSetup_whenTransactionCommittedAndRolledBack_checkPreviousStateAchieved() {
+
+        DB db = DBMaker.memoryDB().transactionEnable().make();
+
+        NavigableSet<String> set = db
+          .treeSet("mySet")
+          .serializer(Serializer.STRING)
+          .createOrOpen();
+
+        set.add("One");
+        set.add("Two");
+
+        db.commit();
+
+        assertEquals(2, set.size());
+
+        set.add("Three");
+
+        assertEquals(3, set.size());
+
+        db.rollback();
+
+        assertEquals(2, set.size());
+
+        db.close();
+    }
+}

libraries-2/src/test/java/com/baeldung/okhttp/ResponseDecoderUnitTest.java

@@ -0,0 +1,102 @@
+package com.baeldung.okhttp;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.google.gson.Gson;
+import okhttp3.OkHttpClient;
+import okhttp3.Request;
+import okhttp3.ResponseBody;
+import okhttp3.mockwebserver.MockResponse;
+import okhttp3.mockwebserver.MockWebServer;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+
+import java.io.InputStreamReader;
+
+public class ResponseDecoderUnitTest {
+
+    @Rule public ExpectedException exceptionRule = ExpectedException.none();
+
+    @Rule public MockWebServer server = new MockWebServer();
+
+    SimpleEntity sampleResponse;
+
+    MockResponse mockResponse;
+
+    OkHttpClient client;
+
+    @Before
+    public void setUp() {
+        sampleResponse = new SimpleEntity("Baeldung");
+        client = new OkHttpClient.Builder().build();
+        mockResponse = new MockResponse()
+          .setResponseCode(200)
+          .setHeader("Content-Type", "application/json")
+          .setBody(new Gson().toJson(sampleResponse));
+    }
+
+    @Test
+    public void givenJacksonDecoder_whenGetStringOfResponse_thenExpectSimpleEntity() throws Exception {
+        server.enqueue(mockResponse);
+        Request request = new Request.Builder()
+          .url(server.url(""))
+          .build();
+        ResponseBody responseBody = client
+          .newCall(request)
+          .execute()
+          .body();
+
+        Assert.assertNotNull(responseBody);
+        Assert.assertNotEquals(0, responseBody.contentLength());
+
+        ObjectMapper objectMapper = new ObjectMapper();
+        SimpleEntity entity = objectMapper.readValue(responseBody.string(), SimpleEntity.class);
+
+        Assert.assertNotNull(entity);
+        Assert.assertEquals(sampleResponse.getName(), entity.getName());
+    }
+
+    @Test
+    public void givenGsonDecoder_whenGetByteStreamOfResponse_thenExpectSimpleEntity() throws Exception {
+        server.enqueue(mockResponse);
+        Request request = new Request.Builder()
+          .url(server.url(""))
+          .build();
+        ResponseBody responseBody = client
+          .newCall(request)
+          .execute()
+          .body();
+
+        Assert.assertNotNull(responseBody);
+        Assert.assertNotEquals(0, responseBody.contentLength());
+
+        Gson gson = new Gson();
+        SimpleEntity entity = gson.fromJson(new InputStreamReader(responseBody.byteStream()), SimpleEntity.class);
+
+        Assert.assertNotNull(entity);
+        Assert.assertEquals(sampleResponse.getName(), entity.getName());
+    }
+
+    @Test
+    public void givenGsonDecoder_whenGetStringOfResponse_thenExpectSimpleEntity() throws Exception {
+        server.enqueue(mockResponse);
+        Request request = new Request.Builder()
+          .url(server.url(""))
+          .build();
+        ResponseBody responseBody = client
+          .newCall(request)
+          .execute()
+          .body();
+
+        Assert.assertNotNull(responseBody);
+
+        Gson gson = new Gson();
+        SimpleEntity entity = gson.fromJson(responseBody.string(), SimpleEntity.class);
+
+        Assert.assertNotNull(entity);
+        Assert.assertEquals(sampleResponse.getName(), entity.getName());
+    }
+
+}

libraries-2/src/test/java/com/baeldung/okhttp/SimpleEntity.java

@@ -0,0 +1,22 @@
+package com.baeldung.okhttp;
+
+public class SimpleEntity {
+    protected String name;
+
+    public SimpleEntity(String name) {
+        this.name = name;
+    }
+
+    //no-arg constructor, getters and setters here
+    
+    public SimpleEntity() {
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+}

libraries-2/src/test/java/com/baeldung/parallel_collectors/ParallelCollectorsUnitTest.java

@@ -0,0 +1,168 @@
+package com.baeldung.parallel_collectors;
+
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+import java.util.TreeMap;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ThreadLocalRandom;
+import java.util.stream.Collectors;
+
+import static com.pivovarit.collectors.ParallelCollectors.parallel;
+import static com.pivovarit.collectors.ParallelCollectors.parallelOrdered;
+import static com.pivovarit.collectors.ParallelCollectors.parallelToCollection;
+import static com.pivovarit.collectors.ParallelCollectors.parallelToList;
+import static com.pivovarit.collectors.ParallelCollectors.parallelToMap;
+import static com.pivovarit.collectors.ParallelCollectors.parallelToStream;
+
+public class ParallelCollectorsUnitTest {
+
+    @Test
+    public void shouldProcessInParallelWithStreams() {
+        List<Integer> ids = Arrays.asList(1, 2, 3);
+
+        List<String> results = ids.parallelStream()
+          .map(i -> fetchById(i))
+          .collect(Collectors.toList());
+
+        System.out.println(results);
+    }
+
+    @Test
+    public void shouldProcessInParallelWithParallelCollectors() {
+        ExecutorService executor = Executors.newFixedThreadPool(10);
+
+        List<Integer> ids = Arrays.asList(1, 2, 3);
+
+        CompletableFuture<List<String>> results = ids.stream()
+          .collect(parallelToList(i -> fetchById(i), executor, 4));
+
+        System.out.println(results.join());
+    }
+
+    @Test
+    public void shouldCollectToList() {
+        ExecutorService executor = Executors.newFixedThreadPool(10);
+
+        List<Integer> ids = Arrays.asList(1, 2, 3);
+
+        List<String> results = ids.stream()
+          .collect(parallelToList(i -> fetchById(i), executor, 4))
+          .join();
+
+        System.out.println(results); // [user-1, user-2, user-3]
+    }
+
+    @Test
+    public void shouldCollectToCollection() {
+        ExecutorService executor = Executors.newFixedThreadPool(10);
+
+        List<Integer> ids = Arrays.asList(1, 2, 3);
+
+        List<String> results = ids.stream()
+          .collect(parallelToCollection(i -> fetchById(i), LinkedList::new, executor, 4))
+          .join();
+
+        System.out.println(results); // [user-1, user-2, user-3]
+    }
+
+    @Test
+    public void shouldCollectToStream() {
+        ExecutorService executor = Executors.newFixedThreadPool(10);
+
+        List<Integer> ids = Arrays.asList(1, 2, 3);
+
+        Map<Integer, List<String>> results = ids.stream()
+          .collect(parallelToStream(i -> fetchById(i), executor, 4))
+          .thenApply(stream -> stream.collect(Collectors.groupingBy(i -> i.length())))
+          .join();
+
+        System.out.println(results); // [user-1, user-2, user-3]
+    }
+
+    @Test
+    public void shouldStreamInCompletionOrder() {
+        ExecutorService executor = Executors.newFixedThreadPool(10);
+
+        List<Integer> ids = Arrays.asList(1, 2, 3);
+
+        ids.stream()
+          .collect(parallel(i -> fetchByIdWithRandomDelay(i), executor, 4))
+          .forEach(System.out::println);
+    }
+
+    @Test
+    public void shouldStreamInOriginalOrder() {
+        ExecutorService executor = Executors.newFixedThreadPool(10);
+
+        List<Integer> ids = Arrays.asList(1, 2, 3);
+
+        ids.stream()
+          .collect(parallelOrdered(i -> fetchByIdWithRandomDelay(i), executor, 4))
+          .forEach(System.out::println);
+    }
+
+    @Test
+    public void shouldCollectToMap() {
+        ExecutorService executor = Executors.newFixedThreadPool(10);
+
+        List<Integer> ids = Arrays.asList(1, 2, 3);
+
+        Map<Integer, String> results = ids.stream()
+          .collect(parallelToMap(i -> i, i -> fetchById(i), executor, 4))
+          .join();
+
+        System.out.println(results); // {1=user-1, 2=user-2, 3=user-3}
+    }
+
+    @Test
+    public void shouldCollectToTreeMap() {
+        ExecutorService executor = Executors.newFixedThreadPool(10);
+
+        List<Integer> ids = Arrays.asList(1, 2, 3);
+
+        Map<Integer, String> results = ids.stream()
+          .collect(parallelToMap(i -> i, i -> fetchById(i), TreeMap::new,  executor, 4))
+          .join();
+
+        System.out.println(results); // {1=user-1, 2=user-2, 3=user-3}
+    }
+
+    @Test
+    public void shouldCollectToTreeMapAndResolveClashes() {
+        ExecutorService executor = Executors.newFixedThreadPool(10);
+
+        List<Integer> ids = Arrays.asList(1, 2, 3);
+
+        Map<Integer, String> results = ids.stream()
+          .collect(parallelToMap(i -> i, i -> fetchById(i), TreeMap::new, (s1, s2) -> s1,   executor, 4))
+          .join();
+
+        System.out.println(results); // {1=user-1, 2=user-2, 3=user-3}
+    }
+
+    private static String fetchById(int id) {
+        try {
+            Thread.sleep(100);
+        } catch (InterruptedException e) {
+            // ignore shamelessly
+        }
+
+        return "user-" + id;
+    }
+
+    private static String fetchByIdWithRandomDelay(int id) {
+        try {
+            Thread.sleep(ThreadLocalRandom.current().nextInt(1000));
+        } catch (InterruptedException e) {
+            // ignore shamelessly
+        }
+
+        return "user-" + id;
+    }
+}

libraries-2/src/test/resources/classgraph/my.config

@@ -0,0 +1 @@
+my data

libraries-2/src/test/resources/greeting.hbs

@@ -0,0 +1 @@
+Hi {{name}}!

libraries-2/src/test/resources/handlebars/each.html

@@ -0,0 +1,3 @@
+{{#each friends}}
+<span>{{name}} is my friend.</span>
+{{/each}}

libraries-2/src/test/resources/handlebars/each_mustache.html

@@ -0,0 +1,3 @@
+{{#each friends}}
+<span>{{name}} is my friend.</span>
+{{/each}}

libraries-2/src/test/resources/handlebars/greeting.html

@@ -0,0 +1 @@
+Hi {{name}}!

libraries-2/src/test/resources/handlebars/header.html

@@ -0,0 +1 @@
+<h4>Hi {{name}}!</h4>

libraries-2/src/test/resources/handlebars/if.html

@@ -0,0 +1,5 @@
+{{#if busy}}
+<h4>{{name}} is busy.</h4>
+{{else}}
+<h4>{{name}} is not busy.</h4>
+{{/if}}

libraries-2/src/test/resources/handlebars/if_mustache.html

@@ -0,0 +1,5 @@
+{{#if busy}}
+<h4>{{name}} is busy.</h4>
+{{^}}
+<h4>{{name}} is not busy.</h4>
+{{/if}}

libraries-2/src/test/resources/handlebars/messagebase.html

@@ -0,0 +1,9 @@
+<html>
+<body>
+{{#block "intro"}}
+  This is the intro
+{{/block}}
+{{#block "message"}}
+{{/block}}
+</body>
+</html>

libraries-2/src/test/resources/handlebars/page.html

@@ -0,0 +1,2 @@
+{{>header}}
+<p>This is the page {{name}}</p>

libraries-2/src/test/resources/handlebars/person.html

@@ -0,0 +1 @@
+{{#isBusy this}}{{/isBusy}}

libraries-2/src/test/resources/handlebars/simplemessage.html

@@ -0,0 +1,4 @@
+{{#partial "message" }}
+  Hi there!
+{{/partial}}
+{{> messagebase}}

libraries-2/src/test/resources/handlebars/with.html

@@ -0,0 +1,3 @@
+{{#with address}}
+<h4>I live in {{street}}</h4>
+{{/with}}

libraries-2/src/test/resources/handlebars/with_mustache.html

@@ -0,0 +1,3 @@
+{{#address}}
+<h4>I live in {{street}}</h4>
+{{/address}}