Merge branch 'master' into master

activejdbc/pom.xml

@@ -0,0 +1,129 @@
+<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>
+  <groupId>com.baeldung</groupId>
+  <artifactId>activejdbc</artifactId>
+  <version>1.0-SNAPSHOT</version>
+  <packaging>jar</packaging>
+  <name>activejdbc</name>
+  <url>http://maven.apache.org</url>
+  <properties>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <activejdbc.version>1.4.13</activejdbc.version>
+    <environments>development.test,development</environments>
+  </properties>
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>3.6.0</version>
+        <configuration>
+          <source>1.8</source>
+          <target>1.8</target>
+          <encoding>UTF-8</encoding>
+        </configuration>
+      </plugin>
+      <plugin>
+        <groupId>org.javalite</groupId>
+        <artifactId>activejdbc-instrumentation</artifactId>
+        <version>${activejdbc.version}</version>
+        <executions>
+          <execution>
+            <phase>process-classes</phase>
+            <goals>
+              <goal>instrument</goal>
+            </goals>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <groupId>org.javalite</groupId>
+        <artifactId>db-migrator-maven-plugin</artifactId>
+        <version>${activejdbc.version}</version>
+        <configuration>
+          <configFile>${project.basedir}/src/main/resources/database.properties</configFile>
+          <environments>${environments}</environments>
+        </configuration>
+        <dependencies>
+          <dependency>
+            <groupId>mysql</groupId>
+            <artifactId>mysql-connector-java</artifactId>
+            <version>5.1.34</version>
+          </dependency>
+        </dependencies>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <version>2.18.1</version>
+        <configuration>
+          <reportFormat>brief</reportFormat>
+          <trimStackTrace>true</trimStackTrace>
+          <useFile>false</useFile>
+          <includes>
+            <include>**/*Spec*.java</include>
+            <include>**/*Test*.java</include>
+          </includes>
+          <excludes>
+            <exclude>**/helpers/*</exclude>
+            <exclude>**/*$*</exclude>
+          </excludes>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+  <dependencies>
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <version>4.12</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.javalite</groupId>
+      <artifactId>activejdbc</artifactId>
+      <version>${activejdbc.version}</version>
+      <exclusions>
+        <exclusion>
+          <groupId>opensymphony</groupId>
+          <artifactId>oscache</artifactId>
+        </exclusion>
+      </exclusions>
+    </dependency>
+    <dependency>
+      <groupId>mysql</groupId>
+      <artifactId>mysql-connector-java</artifactId>
+      <version>5.1.34</version>
+    </dependency>
+    <dependency>
+      <groupId>org.slf4j</groupId>
+      <artifactId>slf4j-simple</artifactId>
+      <version>1.7.9</version>
+    </dependency>
+  </dependencies>
+  <repositories>
+    <repository>
+      <id>snapshots1</id>
+      <name>JavaLite Snapshots1</name>
+      <url>http://repo.javalite.io/</url>
+      <snapshots>
+        <enabled>true</enabled>
+        <updatePolicy>always</updatePolicy>
+        <checksumPolicy>warn</checksumPolicy>
+      </snapshots>
+    </repository>
+  </repositories>
+  <pluginRepositories>
+    <pluginRepository>
+      <id>snapshots2</id>
+      <name>JavaLite Snapshots2</name>
+      <url>http://repo.javalite.io/</url>
+      <snapshots>
+        <enabled>true</enabled>
+        <updatePolicy>always</updatePolicy>
+        <checksumPolicy>warn</checksumPolicy>
+      </snapshots>
+    </pluginRepository>
+  </pluginRepositories>
+</project>

activejdbc/src/main/java/com/baeldung/ActiveJDBCApp.java

@@ -0,0 +1,61 @@
+package com.baeldung;
+
+
+import com.baeldung.model.Employee;
+import com.baeldung.model.Role;
+import org.javalite.activejdbc.Base;
+import org.javalite.activejdbc.LazyList;
+import org.javalite.activejdbc.Model;
+
+public class ActiveJDBCApp
+{
+    public static void main( String[] args )
+    {
+        try {
+            Base.open();
+            ActiveJDBCApp app = new ActiveJDBCApp();
+            app.create();
+            app.update();
+            app.delete();
+            app.deleteCascade();
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            Base.close();
+        }
+    }
+
+    protected void create() {
+        Employee employee = new Employee("Hugo","C","M","BN");
+        employee.saveIt();
+        employee.add(new Role("Java Developer","BN"));
+        LazyList<Model> all = Employee.findAll();
+        System.out.println(all.size());
+    }
+
+    protected void update() {
+        Employee employee = Employee.findFirst("first_name = ?","Hugo");
+        employee.set("last_namea","Choi").saveIt();
+        employee = Employee.findFirst("last_name = ?","Choi");
+        System.out.println(employee.getString("first_name") + " " + employee.getString("last_name"));
+    }
+
+    protected void delete() {
+        Employee employee = Employee.findFirst("first_name = ?","Hugo");
+        employee.delete();
+        employee = Employee.findFirst("last_name = ?","Choi");
+        if(null == employee){
+            System.out.println("No such Employee found!");
+        }
+    }
+
+    protected void deleteCascade() {
+        create();
+        Employee employee = Employee.findFirst("first_name = ?","Hugo");
+        employee.deleteCascade();
+        employee = Employee.findFirst("last_name = ?","C");
+        if(null == employee){
+            System.out.println("No such Employee found!");
+        }
+    }
+}

activejdbc/src/main/java/com/baeldung/model/Employee.java

@@ -0,0 +1,19 @@
+package com.baeldung.model;
+
+
+import org.javalite.activejdbc.Model;
+
+public class Employee extends Model {
+
+    public Employee(){
+
+    }
+
+    public Employee(String firstName, String lastName, String gender, String createdBy) {
+        set("first_name1",firstName);
+        set("last_name",lastName);
+        set("gender",gender);
+        set("created_by",createdBy);
+    }
+
+}

activejdbc/src/main/java/com/baeldung/model/Role.java

@@ -0,0 +1,18 @@
+package com.baeldung.model;
+
+
+import org.javalite.activejdbc.Model;
+import org.javalite.activejdbc.annotations.Table;
+
+@Table("EMP_ROLES")
+public class Role extends Model {
+
+    public Role(){
+
+    }
+
+    public Role(String role,String createdBy){
+        set("role_name",role);
+        set("created_by",createdBy);
+    }
+}

activejdbc/src/main/migration/_create_tables.sql

@@ -0,0 +1,25 @@
+# noinspection SqlNoDataSourceInspectionForFile
+
+create table organisation.employees
+(
+	id int not null auto_increment
+		primary key,
+	first_name varchar(100) not null,
+	last_name varchar(100) not null,
+	gender varchar(1) not null,
+	created_at datetime not null,
+	updated_at datetime null,
+	created_by varchar(100) not null,
+	updated_by varchar(100) null
+)ENGINE = InnoDB DEFAULT CHARSET = utf8;
+
+create table organisation.emp_roles
+(
+	id int not null auto_increment primary key,
+	employee_id int not null,
+	role_name varchar(100) not null,
+	created_at datetime not null,
+	updated_at datetime null,
+	created_by varchar(100) not null,
+	updated_by varchar(100) null
+)ENGINE = InnoDB DEFAULT CHARSET = utf8;

activejdbc/src/main/resources/database.properties

@@ -0,0 +1,10 @@
+development.driver=com.mysql.jdbc.Driver
+development.username=root
+development.password=123456
+development.url=jdbc:mysql://localhost/organisation
+
+
+development.test.driver=com.mysql.jdbc.Driver
+development.test.username=root
+development.test.password=123456
+development.test.url=jdbc:mysql://localhost/organisation_test

activejdbc/src/test/java/com/baeldung/ActiveJDBCAppTest.java

@@ -0,0 +1,51 @@
+package com.baeldung;
+
+import com.baeldung.model.Employee;
+import com.baeldung.model.Role;
+import org.javalite.activejdbc.test.DBSpec;
+import org.junit.Test;
+
+import java.util.List;
+
+public class ActiveJDBCAppTest extends DBSpec
+{
+    @Test
+    public void ifEmployeeCreated_thenIsValid() {
+        Employee employee = new Employee("B", "N", "M", "BN");
+        the(employee).shouldBe("valid");
+    }
+
+    @Test
+    public void ifEmployeeCreatedWithRoles_thenShouldPersist() {
+        Employee employee = new Employee("B", "N", "M", "BN");
+        employee.saveIt();
+        employee.add(new Role("Java Developer","BN"));
+        employee.add(new Role("Lead Java Developer","BN"));
+        a(Role.count()).shouldBeEqual(2);
+        List<Role> roles = employee.getAll(Role.class).orderBy("created_at");
+        the(roles.get(0).getRoleName()).shouldBeEqual("Java Developer");
+        the(roles.get(1).getRoleName()).shouldBeEqual("Lead Java Developer");
+    }
+
+    @Test
+    public void ifEmployeeCreatedWithRoles_whenNameUpdated_thenShouldShowNewName() {
+        Employee employee = new Employee("Binesh", "N", "M", "BN");
+        employee.saveIt();
+        employee.add(new Role("Java Developer","BN"));
+        employee.add(new Role("Lead Java Developer","BN"));
+        employee = Employee.findFirst("first_name = ?", "Binesh");
+        employee.set("last_name","Narayanan").saveIt();
+        Employee updated = Employee.findFirst("first_name = ?", "Binesh");
+        the(updated.getLastName()).shouldBeEqual("Narayanan");
+    }
+
+    @Test
+    public void ifEmployeeCreatedWithRoles_whenDeleted_thenShouldNotBeFound() {
+        Employee employee = new Employee("Binesh", "N", "M", "BN");
+        employee.saveIt();
+        employee.add(new Role("Java Developer","BN"));
+        employee.delete();
+        employee = Employee.findFirst("first_name = ?", "Binesh");
+        the(employee).shouldBeNull();
+    }
+}

apache-poi/README.md

@@ -1,3 +1,4 @@
 ### Relevant Articles:
 - [Microsoft Word Processing in Java with Apache POI](http://www.baeldung.com/java-microsoft-word-with-apache-poi)
 - [Working with Microsoft Excel in Java](http://www.baeldung.com/java-microsoft-excel)
+- [Creating a MS PowerPoint Presentation in Java](https://github.com/eugenp/tutorials/tree/master/apache-poi)

core-java-8/README.md

@@ -37,3 +37,6 @@
 - [Iterable to Stream in Java](http://www.baeldung.com/java-iterable-to-stream)
 - [Converting String to Stream of chars](http://www.baeldung.com/java-string-to-stream)
 - [How to Iterate Over a Stream With Indices](http://www.baeldung.com/java-stream-indices)
+- [Efficient Word Frequency Calculator in Java](http://www.baeldung.com/java-word-frequency)
+- [Primitive Type Streams in Java 8](http://www.baeldung.com/java-8-primitive-streams)
+- [Fail-Safe Iterator vs Fail-Fast Iterator](http://www.baeldung.com/java-fail-safe-vs-fail-fast-iterator)

core-java-8/src/main/java/com/baeldung/spliteratorAPI/Executor.java

@@ -1,45 +1,19 @@
 package com.baeldung.spliteratorAPI;
 
-import java.util.Arrays;
 import java.util.List;
-import java.util.Spliterator;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
 import java.util.stream.Collectors;
-import java.util.stream.IntStream;
 import java.util.stream.Stream;
-import java.util.stream.StreamSupport;
 
 public class Executor {
-	public void executeCustomSpliterator() {
-        Article article = new Article(Arrays.asList(new Author("Ahmad", 0), new Author("Eugen", 0), new Author("Alice", 1), new Author("Alice", 1), new Author("Mike", 0), new Author("Alice", 1), new Author("Mike", 0), new Author("Alice", 1),
-            new Author("Mike", 0), new Author("Alice", 1), new Author("Mike", 0), new Author("Mike", 0), new Author("Alice", 1), new Author("Mike", 0), new Author("Alice", 1), new Author("Mike", 0), new Author("Alice", 1), new Author("Mike", 0),
-            new Author("Alice", 1), new Author("Mike", 0), new Author("Michał", 0), new Author("Loredana", 1)), 0);
-        Stream<Author> stream = IntStream.range(0, article.getListOfAuthors()
-            .size())
-            .mapToObj(article.getListOfAuthors()::get);
-        System.out.println("count= " + countAutors(stream.parallel()));
-        Spliterator<Author> spliterator = new RelatedAuthorSpliterator(article.getListOfAuthors());
-        Stream<Author> stream2 = StreamSupport.stream(spliterator, true);
-        System.out.println("count= " + countAutors(stream2.parallel()));
-    }
 
-    public void executeSpliterator() {
-        Spliterator<Article> split1 = generateElements().spliterator();
-        Spliterator<Article> split2 = split1.trySplit();
-        ExecutorService service = Executors.newCachedThreadPool();
-        service.execute(new Task(split1));
-        service.execute(new Task(split2));
-    }
+	public static int countAutors(Stream<Author> stream) {
+		RelatedAuthorCounter wordCounter = stream.reduce(new RelatedAuthorCounter(0, true),
+				RelatedAuthorCounter::accumulate, RelatedAuthorCounter::combine);
+		return wordCounter.getCounter();
+	}
 
-    private static int countAutors(Stream<Author> stream) {
-        RelatedAuthorCounter wordCounter = stream.reduce(new RelatedAuthorCounter(0, true), RelatedAuthorCounter::accumulate, RelatedAuthorCounter::combine);
-        return wordCounter.getCounter();
-    }
+	public static List<Article> generateElements() {
+		return Stream.generate(() -> new Article("Java")).limit(35000).collect(Collectors.toList());
+	}
 
-    private List<Article> generateElements() {
-        return Stream.generate(() -> new Article("Java"))
-            .limit(35000)
-            .collect(Collectors.toList());
-    }
-}
+}

core-java-8/src/main/java/com/baeldung/spliteratorAPI/Task.java

@@ -1,8 +1,9 @@
 package com.baeldung.spliteratorAPI;
 
 import java.util.Spliterator;
+import java.util.concurrent.Callable;
 
-public class Task implements Runnable {
+public class Task implements Callable<String> {
     private Spliterator<Article> spliterator;
     private final static String SUFFIX = "- published by Baeldung";
 
@@ -11,7 +12,7 @@ public class Task implements Runnable {
     }
 
     @Override
-    public void run() {
+    public String call() {
         int current = 0;
         while (spliterator.tryAdvance(article -> {
             article.setName(article.getName()
@@ -20,7 +21,7 @@ public class Task implements Runnable {
             current++;
         }
         ;
-        System.out.println(Thread.currentThread()
-            .getName() + ":" + current);
+        return Thread.currentThread()
+            .getName() + ":" + current;
     }
 }

core-java-8/src/test/java/com/baeldung/spliteratorAPI/ExecutorTest.java

@@ -0,0 +1,44 @@
+package com.baeldung.spliteratorAPI;
+
+import java.util.Arrays;
+import java.util.Spliterator;
+import java.util.stream.Stream;
+import java.util.stream.StreamSupport;
+
+import static org.assertj.core.api.Assertions.*;
+import org.junit.Before;
+import org.junit.Test;
+
+public class ExecutorTest {
+	Article article;
+	Stream<Author> stream;
+	Spliterator<Author> spliterator;
+	Spliterator<Article> split1;
+	Spliterator<Article> split2;
+
+	@Before
+	public void init() {
+		article = new Article(Arrays.asList(new Author("Ahmad", 0), new Author("Eugen", 0), new Author("Alice", 1),
+				new Author("Alice", 1), new Author("Mike", 0), new Author("Alice", 1), new Author("Mike", 0),
+				new Author("Alice", 1), new Author("Mike", 0), new Author("Alice", 1), new Author("Mike", 0),
+				new Author("Mike", 0), new Author("Alice", 1), new Author("Mike", 0), new Author("Alice", 1),
+				new Author("Mike", 0), new Author("Alice", 1), new Author("Mike", 0), new Author("Alice", 1),
+				new Author("Mike", 0), new Author("Michał", 0), new Author("Loredana", 1)), 0);
+		stream = article.getListOfAuthors().stream();
+		split1 = Executor.generateElements().spliterator();
+		split2 = split1.trySplit();
+		spliterator = new RelatedAuthorSpliterator(article.getListOfAuthors());
+	}
+
+	@Test
+	public void givenAstreamOfAuthors_whenProcessedInParallelWithCustomSpliterator_coubtProducessRightOutput() {
+		Stream<Author> stream2 = StreamSupport.stream(spliterator, true);
+		assertThat(Executor.countAutors(stream2.parallel())).isEqualTo(9);
+	}
+
+	@Test
+	public void givenSpliterator_whenAppliedToAListOfArticle_thenSplittedInHalf() {
+		assertThat(new Task(split1).call()).containsSequence(Executor.generateElements().size() / 2 + "");
+		assertThat(new Task(split2).call()).containsSequence(Executor.generateElements().size() / 2 + "");
+	}
+}

core-java-concurrency/README.md

@@ -33,3 +33,4 @@
 - [Daemon Threads in Java](http://www.baeldung.com/java-daemon-thread)
 - [Implementing a Runnable vs Extending a Thread](http://www.baeldung.com/java-runnable-vs-extending-thread)
 - [How to Kill a Java Thread](http://www.baeldung.com/java-thread-stop)
+- [ExecutorService - Waiting for Threads to Finish](http://www.baeldung.com/java-executor-wait-for-threads)

core-java/README.md

@@ -118,3 +118,11 @@
 - [Implementing a Binary Tree in Java](http://www.baeldung.com/java-binary-tree)
 - [A Guide to ThreadLocalRandom in Java](http://www.baeldung.com/java-thread-local-random)
 - [RegEx for matching Date Pattern in Java](http://www.baeldung.com/java-date-regular-expressions)
+- [Introduction to the JDBC RowSet Interface in Java](http://www.baeldung.com/java-jdbc-rowset)
+- [Nested Classes in Java](http://www.baeldung.com/java-nested-classes)
+- [A Guide to Java Loops](http://www.baeldung.com/java-loops)
+- [Varargs in Java](http://www.baeldung.com/java-varargs)
+- [A Guide to HashSet in Java](http://www.baeldung.com/java-hashset)
+- [A Guide to Inner Interfaces in Java](http://www.baeldung.com/java-inner-interfaces)
+- [Polymorphism in Java](http://www.baeldung.com/java-polymorphism)
+- [Recursion In Java](http://www.baeldung.com/java-recursion)

core-java/src/main/java/com/baeldung/finalize/CloseableResource.java

@@ -0,0 +1,30 @@
+package com.baeldung.finalize;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+
+public class CloseableResource implements AutoCloseable {
+    private BufferedReader reader;
+
+    public CloseableResource() {
+        InputStream input = this.getClass().getClassLoader().getResourceAsStream("file.txt");
+        reader = new BufferedReader(new InputStreamReader(input));
+    }
+
+    public String readFirstLine() throws IOException {
+        String firstLine = reader.readLine();
+        return firstLine;
+    }
+
+    @Override
+    public void close() {
+        try {
+            reader.close();
+            System.out.println("Closed BufferedReader in the close method");
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+}

core-java/src/main/java/com/baeldung/finalize/Finalizable.java

@@ -0,0 +1,30 @@
+package com.baeldung.finalize;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+
+public class Finalizable {
+    private BufferedReader reader;
+
+    public Finalizable() {
+        InputStream input = this.getClass().getClassLoader().getResourceAsStream("file.txt");
+        reader = new BufferedReader(new InputStreamReader(input));
+    }
+
+    public String readFirstLine() throws IOException {
+        String firstLine = reader.readLine();
+        return firstLine;
+    }
+
+    @Override
+    public void finalize() {
+        try {
+            reader.close();
+            System.out.println("Closed BufferedReader in the finalizer");
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+}

core-java/src/main/java/com/baeldung/trie/Trie.java

@@ -0,0 +1,62 @@
+package com.baeldung.trie;
+
+public class Trie {
+    private TrieNode root;
+
+    Trie() {
+        root = new TrieNode();
+    }
+
+    public void insert(String word) {
+        TrieNode current = root;
+
+        for (int i = 0; i < word.length(); i++) {
+            current = current.getChildren().computeIfAbsent(word.charAt(i), c -> new TrieNode());
+        }
+        current.setEndOfWord(true);
+    }
+
+    public boolean delete(String word) {
+        return delete(root, word, 0);
+    }
+
+    public boolean containsNode(String word) {
+        TrieNode current = root;
+
+        for (int i = 0; i < word.length(); i++) {
+            char ch = word.charAt(i);
+            TrieNode node = current.getChildren().get(ch);
+            if (node == null) {
+                return false;
+            }
+            current = node;
+        }
+        return current.isEndOfWord();
+    }
+
+    public boolean isEmpty() {
+        return root == null;
+    }
+
+    private boolean delete(TrieNode current, String word, int index) {
+        if (index == word.length()) {
+            if (!current.isEndOfWord()) {
+                return false;
+            }
+            current.setEndOfWord(false);
+            return current.getChildren().isEmpty();
+        }
+        char ch = word.charAt(index);
+        TrieNode node = current.getChildren().get(ch);
+        if (node == null) {
+            return false;
+        }
+        boolean shouldDeleteCurrentNode = delete(node, word, index + 1);
+
+        if (shouldDeleteCurrentNode) {
+            current.getChildren().remove(ch);
+            return current.getChildren().isEmpty();
+        }
+        return false;
+    }
+}

core-java/src/main/java/com/baeldung/trie/TrieNode.java

@@ -0,0 +1,31 @@
+package com.baeldung.trie;
+
+import java.util.HashMap;
+import java.util.Map;
+
+class TrieNode {
+    private Map<Character, TrieNode> children;
+    private boolean endOfWord;
+
+    public TrieNode() {
+        children = new HashMap<>();
+        endOfWord = false;
+    }
+
+    public Map<Character, TrieNode> getChildren() {
+        return children;
+    }
+
+    public void setChildren(Map<Character, TrieNode> children) {
+        this.children = children;
+    }
+
+    public boolean isEndOfWord() {
+        return endOfWord;
+    }
+
+    public void setEndOfWord(boolean endOfWord) {
+        this.endOfWord = endOfWord;
+    }
+
+}

core-java/src/test/java/com/baeldung/finalize/FinalizeUnitTest.java

@@ -0,0 +1,23 @@
+package com.baeldung.finalize;
+
+import java.io.IOException;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class FinalizeUnitTest {
+    @Test
+    public void whenGC_thenFinalizerExecuted() throws IOException {
+        String firstLine = new Finalizable().readFirstLine();
+        Assert.assertEquals("baeldung.com", firstLine);
+        System.gc();
+    }
+
+    @Test
+    public void whenTryWResourcesExits_thenResourceClosed() throws IOException {
+        try (CloseableResource resource = new CloseableResource()) {
+            String firstLine = resource.readFirstLine();
+            Assert.assertEquals("baeldung.com", firstLine);
+        }
+    }
+}

core-java/src/test/java/com/baeldung/trie/TrieTest.java

@@ -0,0 +1,68 @@
+package com.baeldung.trie;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+public class TrieTest {
+
+    @Test
+    public void whenEmptyTrie_thenNoElements() {
+        Trie trie = new Trie();
+
+        assertFalse(trie.isEmpty());
+    }
+
+    @Test
+    public void givenATrie_whenAddingElements_thenTrieNotEmpty() {
+        Trie trie = createExampleTrie();
+
+        assertFalse(trie.isEmpty());
+    }
+
+    @Test
+    public void givenATrie_whenAddingElements_thenTrieHasThoseElements() {
+        Trie trie = createExampleTrie();
+
+        assertFalse(trie.containsNode("3"));
+        assertFalse(trie.containsNode("vida"));
+
+        assertTrue(trie.containsNode("Programming"));
+        assertTrue(trie.containsNode("is"));
+        assertTrue(trie.containsNode("a"));
+        assertTrue(trie.containsNode("way"));
+        assertTrue(trie.containsNode("of"));
+        assertTrue(trie.containsNode("life"));
+    }
+
+    @Test
+    public void givenATrie_whenLookingForNonExistingElement_thenReturnsFalse() {
+        Trie trie = createExampleTrie();
+
+        assertFalse(trie.containsNode("99"));
+    }
+
+    @Test
+    public void givenATrie_whenDeletingElements_thenTreeDoesNotContainThoseElements() {
+
+        Trie trie = createExampleTrie();
+
+        assertTrue(trie.containsNode("Programming"));
+        trie.delete("Programming");
+        assertFalse(trie.containsNode("Programming"));
+    }
+
+    private Trie createExampleTrie() {
+        Trie trie = new Trie();
+
+        trie.insert("Programming");
+        trie.insert("is");
+        trie.insert("a");
+        trie.insert("way");
+        trie.insert("of");
+        trie.insert("life");
+
+        return trie;
+    }
+}

core-kotlin/README.md

@@ -16,5 +16,5 @@
 - [Delegated Properties in Kotlin](http://www.baeldung.com/kotlin-delegated-properties)
 - [Sealed Classes in Kotlin](http://www.baeldung.com/kotlin-sealed-classes)
 - [JUnit 5 for Kotlin Developers](http://www.baeldung.com/junit-5-kotlin)
-
+- [Extension Methods in Kotlin](http://www.baeldung.com/kotlin-extension-methods)
 

core-kotlin/pom.xml

@@ -49,6 +49,11 @@
             <artifactId>kotlin-stdlib-jre8</artifactId>
             <version>${kotlin-stdlib.version}</version>
         </dependency>
+        <dependency>
+            <groupId>khttp</groupId>
+            <artifactId>khttp</artifactId>
+            <version>0.1.0</version>
+        </dependency>
         <dependency>
             <groupId>org.jetbrains.kotlin</groupId>
             <artifactId>kotlin-test-junit</artifactId>

core-kotlin/src/test/kotlin/com/baeldung/kotlin/khttp/KhttpTest.kt

@@ -0,0 +1,153 @@
+package com.baeldung.kotlin.khttp
+
+import khttp.structures.files.FileLike
+import org.json.JSONObject
+import org.junit.Test
+import java.beans.ExceptionListener
+import java.beans.XMLEncoder
+import java.io.*
+import java.lang.Exception
+import java.net.ConnectException
+import kotlin.test.assertEquals
+import kotlin.test.assertTrue
+import kotlin.test.fail
+
+class KhttpTest {
+
+    @Test
+    fun whenHttpGetRequestIsMade_thenArgsAreReturned() {
+        val response = khttp.get(
+                url = "http://httpbin.org/get",
+                params = mapOf("p1" to "1", "p2" to "2"))
+        val args = response.jsonObject.getJSONObject("args")
+
+        assertEquals("1", args["p1"])
+        assertEquals("2", args["p2"])
+    }
+
+    @Test
+    fun whenAlternateHttpGetRequestIsMade_thenArgsAreReturned() {
+        val response = khttp.request(
+                method = "GET",
+                url = "http://httpbin.org/get",
+                params = mapOf("p1" to "1", "p2" to "2"))
+        val args = response.jsonObject.getJSONObject("args")
+
+        assertEquals("1", args["p1"])
+        assertEquals("2", args["p2"])
+    }
+
+    @Test
+    fun whenHeadersAreSet_thenHeadersAreSent() {
+        val response = khttp.get(
+                url = "http://httpbin.org/get",
+                headers = mapOf("header1" to "1", "header2" to "2"))
+        val headers = response.jsonObject.getJSONObject("headers")
+
+        assertEquals("1", headers["Header1"])
+        assertEquals("2", headers["Header2"])
+    }
+
+    @Test
+    fun whenHttpPostRequestIsMadeWithJson_thenBodyIsReturned() {
+        val response = khttp.post(
+                url = "http://httpbin.org/post",
+                params = mapOf("p1" to "1", "p2" to "2"),
+                json = mapOf("pr1" to "1", "pr2" to "2"))
+
+        val args = response.jsonObject.getJSONObject("args")
+
+        assertEquals("1", args["p1"])
+        assertEquals("2", args["p2"])
+
+        val json = response.jsonObject.getJSONObject("json")
+
+        assertEquals("1", json["pr1"])
+        assertEquals("2", json["pr2"])
+    }
+
+    @Test
+    fun whenHttpPostRequestIsMadeWithMapData_thenBodyIsReturned() {
+        val response = khttp.post(
+                url = "http://httpbin.org/post",
+                params = mapOf("p1" to "1", "p2" to "2"),
+                data = mapOf("pr1" to "1", "pr2" to "2"))
+
+        val args = response.jsonObject.getJSONObject("args")
+
+        assertEquals("1", args["p1"])
+        assertEquals("2", args["p2"])
+
+        val form = response.jsonObject.getJSONObject("form")
+
+        assertEquals("1", form["pr1"])
+        assertEquals("2", form["pr2"])
+    }
+
+    @Test
+    fun whenHttpPostRequestIsMadeWithFiles_thenBodyIsReturned() {
+        val response = khttp.post(
+                url = "http://httpbin.org/post",
+                params = mapOf("p1" to "1", "p2" to "2"),
+                files = listOf(
+                        FileLike("file1", "content1"),
+                        FileLike("file2", javaClass.getResource("KhttpTest.class").openStream().readBytes())))
+
+        val args = response.jsonObject.getJSONObject("args")
+
+        assertEquals("1", args["p1"])
+        assertEquals("2", args["p2"])
+
+        val files = response.jsonObject.getJSONObject("files")
+
+        assertEquals("content1", files["file1"])
+    }
+
+    @Test
+    fun whenHttpPostRequestIsMadeWithInputStream_thenBodyIsReturned() {
+        val response = khttp.post(
+                url = "http://httpbin.org/post",
+                params = mapOf("p1" to "1", "p2" to "2"),
+                data = ByteArrayInputStream("content!".toByteArray()))
+
+        val args = response.jsonObject.getJSONObject("args")
+
+        assertEquals("1", args["p1"])
+        assertEquals("2", args["p2"])
+
+        assertEquals("content!", response.jsonObject["data"])
+    }
+
+    @Test
+    fun whenHttpPostStreamingRequestIsMade_thenBodyIsReturnedInChunks() {
+        val response = khttp.post(
+                url = "http://httpbin.org/post",
+                stream = true,
+                json = mapOf("pr1" to "1", "pr2" to "2"))
+
+        val baos = ByteArrayOutputStream()
+        response.contentIterator(chunkSize = 10).forEach { arr : ByteArray -> baos.write(arr) }
+        val json = JSONObject(String(baos.toByteArray())).getJSONObject("json")
+
+        assertEquals("1", json["pr1"])
+        assertEquals("2", json["pr2"])
+    }
+
+    @Test
+    fun whenHttpRequestFails_thenExceptionIsThrown() {
+        try {
+            khttp.get(url = "http://localhost/nothing/to/see/here")
+
+            fail("Should have thrown an exception")
+        } catch (e : ConnectException) {
+            //Ok
+        }
+    }
+
+    @Test
+    fun whenHttpNotFound_thenExceptionIsThrown() {
+        val response = khttp.get(url = "http://httpbin.org/nothing/to/see/here")
+
+        assertEquals(404, response.statusCode)
+    }
+}

dubbo/README.md

@@ -1,4 +1,4 @@
 ## Relevant articles:
 
-- [Intro to Dubbo](http://www.baeldung.com/dubbo-intro)
+- [Introduction to Dubbo](http://www.baeldung.com/dubbo)
 

flyway/README.MD

@@ -1,2 +1,3 @@
 ### Relevant Articles:
 - [Database Migrations with Flyway](http://www.baeldung.com/database-migrations-with-flyway)
+- [A Guide to Flyway Callbacks](http://www.baeldung.com/flyway-callbacks)

gradle/README.md

@@ -1,2 +1,4 @@
 ## Relevant articles:
 - [Introduction to Gradle](http://www.baeldung.com/gradle)
+- [Writing Custom Gradle Plugins](http://www.baeldung.com/gradle-create-plugin)
+- [Creating a Fat Jar in Gradle](http://www.baeldung.com/gradle-fat-jar)

guest/deep-jsf/README.md

@@ -0,0 +1,15 @@
+## Building
+
+To build the module, use Maven's `package` goal:
+
+```
+mvn clean package
+```
+
+The `war` file will be available at `target/deep-jsf.war`
+
+## Running
+
+The `war` application is deployed to a Java EE 7 compliant application server, for example, to GlassFish 4 or later.
+
+The example then will be accessible at http://localhost:8080/deep-jsf/index.xhtml

guest/deep-jsf/pom.xml

@@ -0,0 +1,40 @@
+<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>
+
+    <groupId>com.stackify</groupId>
+    <artifactId>deep-jsf</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <packaging>war</packaging>
+
+    <properties>
+        <failOnMissingWebXml>false</failOnMissingWebXml>
+    </properties>
+
+    <dependencies>
+
+        <dependency>
+            <groupId>javax</groupId>
+            <artifactId>javaee-api</artifactId>
+            <version>7.0</version>
+            <scope>provided</scope>
+        </dependency>
+
+    </dependencies>
+
+    <build>
+        <finalName>deep-jsf</finalName>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.7.0</version>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>

guest/deep-jsf/src/main/java/com/stackify/deepjsf/GreetControllerBean.java

@@ -0,0 +1,14 @@
+package com.stackify.deepjsf;
+
+import javax.faces.bean.ManagedBean;
+import javax.faces.bean.RequestScoped;
+
+@ManagedBean
+@RequestScoped
+public class GreetControllerBean {
+
+    public String greet() {
+        return "greet";
+    }
+
+}

guest/deep-jsf/src/main/java/com/stackify/deepjsf/PhaseListenerBean.java

@@ -0,0 +1,47 @@
+package com.stackify.deepjsf;
+
+import javax.faces.bean.ManagedBean;
+import javax.faces.bean.RequestScoped;
+import javax.faces.component.UIComponent;
+import javax.faces.component.UIViewRoot;
+import javax.faces.component.visit.VisitContext;
+import javax.faces.component.visit.VisitResult;
+import javax.faces.event.PhaseEvent;
+import javax.faces.event.PhaseId;
+import javax.servlet.http.HttpServletRequest;
+
+@ManagedBean
+@RequestScoped
+public class PhaseListenerBean {
+
+    public void beforeListener(PhaseEvent event) {
+        if (!event.getPhaseId().equals(PhaseId.RENDER_RESPONSE)) {
+            return;
+        }
+        UIViewRoot root = event.getFacesContext().getViewRoot();
+
+        boolean showNewFeature = showNewFeatureForIp(event);
+
+        processComponentTree(root, event, showNewFeature);
+    }
+
+    private boolean showNewFeatureForIp(PhaseEvent event) {
+        HttpServletRequest request = (HttpServletRequest) event.getFacesContext()
+                .getExternalContext().getRequest();
+        String ip = request.getRemoteAddr();
+        return !ip.startsWith("127.0");
+    }
+
+    private void processComponentTree(UIComponent component, PhaseEvent event, boolean show) {
+        component.visitTree(VisitContext.createVisitContext(event.getFacesContext()),
+                (context, target) -> {
+                    if (target.getId() != null
+                            && target.getId().startsWith("new-feature-")
+                            && !show) {
+                        target.setRendered(false);
+                    }
+                    return VisitResult.ACCEPT;
+                });
+    }
+
+}

guest/deep-jsf/src/main/java/com/stackify/deepjsf/UserBean.java

@@ -0,0 +1,48 @@
+package com.stackify.deepjsf;
+
+import javax.faces.bean.ManagedBean;
+import javax.faces.bean.SessionScoped;
+import javax.faces.event.ValueChangeEvent;
+
+@ManagedBean
+@SessionScoped
+public class UserBean {
+
+    private String name = "";
+
+    private String lastName = "";
+
+    private String proposedLogin = "";
+
+    public void nameChanged(ValueChangeEvent event) {
+        this.proposedLogin = event.getNewValue() + "-" + lastName;
+    }
+
+    public void lastNameChanged(ValueChangeEvent event) {
+        this.proposedLogin = name + "-" + event.getNewValue();
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public void setLastName(String lastName) {
+        this.lastName = lastName;
+    }
+
+    public String getProposedLogin() {
+        return proposedLogin;
+    }
+
+    public void setProposedLogin(String proposedLogin) {
+        this.proposedLogin = proposedLogin;
+    }
+}

guest/deep-jsf/src/main/java/com/stackify/deepjsf/UserControllerBean.java

@@ -0,0 +1,14 @@
+package com.stackify.deepjsf;
+
+import javax.faces.bean.ManagedBean;
+import javax.faces.bean.RequestScoped;
+
+@ManagedBean
+@RequestScoped
+public class UserControllerBean {
+
+    public String register() {
+        return "register-success";
+    }
+
+}

guest/deep-jsf/src/main/webapp/WEB-INF/faces-config.xml

@@ -0,0 +1,15 @@
+<?xml version='1.0' encoding='UTF-8'?>
+<faces-config version="2.2" xmlns="http://xmlns.jcp.org/xml/ns/javaee"
+              xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+              xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
+    http://xmlns.jcp.org/xml/ns/javaee/web-facesconfig_2_2.xsd">
+
+    <navigation-rule>
+        <from-view-id>/register.xhtml</from-view-id>
+        <navigation-case>
+            <from-outcome>register-success</from-outcome>
+            <to-view-id>/hello.xhtml</to-view-id>
+        </navigation-case>
+    </navigation-rule>
+
+</faces-config>

guest/deep-jsf/src/main/webapp/greet.xhtml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
+        "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml"
+      xmlns:h="http://xmlns.jcp.org/jsf/html"
+      xmlns:f="http://xmlns.jcp.org/jsf/core">
+<f:view beforePhase="#{phaseListenerBean.beforeListener}">
+    <h:outputLabel value="Hello, #{userBean.name}"/>
+    <h:outputLabel id="new-feature-last-name" value=" #{userBean.lastName}"/>
+</f:view>
+</html>

guest/deep-jsf/src/main/webapp/hello.xhtml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
+        "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml"
+      xmlns:h="http://xmlns.jcp.org/jsf/html"
+      xmlns:f="http://xmlns.jcp.org/jsf/core">
+<f:view>
+    <h:outputLabel value="Hello, #{userBean.name} #{userBean.lastName}! Your login is: #{userBean.proposedLogin}"/>
+</f:view>
+</html>

guest/deep-jsf/src/main/webapp/index.xhtml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
+        "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml"
+      xmlns:h="http://xmlns.jcp.org/jsf/html"
+      xmlns:f="http://xmlns.jcp.org/jsf/core">
+<f:view beforePhase="#{phaseListenerBean.beforeListener}">
+    <h:form>
+        <h:panelGrid columns="2">
+            <h:outputLabel value="First Name:"/>
+            <h:inputText id="name" value="#{userBean.name}"/>
+            <h:outputLabel id="new-feature-last-name-label" value="Last Name:"/>
+            <h:inputText id="new-feature-last-name" value="#{userBean.lastName}"/>
+            <h:commandButton value="Submit" action="#{greetControllerBean.greet}"/>
+        </h:panelGrid>
+    </h:form>
+</f:view>
+</html>

guest/deep-jsf/src/main/webapp/register.xhtml

@@ -0,0 +1,31 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
+        "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<html xmlns="http://www.w3.org/1999/xhtml"
+      xmlns:h="http://xmlns.jcp.org/jsf/html"
+      xmlns:f="http://xmlns.jcp.org/jsf/core">
+
+<h:head>
+    <h:outputScript library="javax.faces" name="jsf.js"/>
+</h:head>
+
+<f:view>
+    <h:form>
+        <h:panelGrid columns="2">
+            <h:outputLabel value="First Name:"/>
+            <h:inputText id="name" value="#{userBean.name}"
+                         valueChangeListener="#{userBean.nameChanged}">
+                <f:ajax event="change" execute="@this" render="proposed-login"/>
+            </h:inputText>
+            <h:outputLabel id="lastname-label" value="Last Name:"/>
+            <h:inputText id="lastname" value="#{userBean.lastName}"
+                         valueChangeListener="#{userBean.lastNameChanged}">
+                <f:ajax event="change" execute="@this" render="proposed-login"/>
+            </h:inputText>
+            <h:outputLabel id="login-label" value="Proposed Login:"/>
+            <h:inputText id="proposed-login" disabled="true" value="#{userBean.proposedLogin}"/>
+            <h:commandButton value="Submit" action="#{userControllerBean.register}"/>
+        </h:panelGrid>
+    </h:form>
+</f:view>
+</html>

hibernate5/README.md

@@ -5,3 +5,5 @@
 - [Hibernate – Mapping Date and Time](http://www.baeldung.com/hibernate-date-time)
 - [Hibernate Inheritance Mapping](http://www.baeldung.com/hibernate-inheritance)
 - [A Guide to Multitenancy in Hibernate 5](http://www.baeldung.com/hibernate-5-multitenancy)
+- [Introduction to Hibernate Spatial](http://www.baeldung.com/hibernate-spatial)
+- [Hibernate Interceptors](http://www.baeldung.com/hibernate-interceptor)

influxdb/README.md

@@ -2,6 +2,7 @@
 
 ### Relevant Article:
 - [Introduction to using InfluxDB with Java](http://www.baeldung.com/using-influxdb-with-java/)
+- [Using InfluxDB with Java](http://www.baeldung.com/java-influxdb)
 
 ### Overview
 This Maven project contains the Java code for the article linked above.

jmeter/README.md

@@ -38,4 +38,9 @@ $ curl -X POST -H "Content-Type:application/json" -d '{ "firstName" : "Dassi", "
 
 Now with default configurations it will be available at: [http://localhost:8080](http://localhost:8080)
 
-Enjoy it :)
+Enjoy it :)
+
+### Relevant Articles:
+
+- [Intro to Performance Testing using JMeter](http://www.baeldung.com/jmeter)
+- [Configure Jenkins to Run and Show JMeter Tests](http://www.baeldung.com/jenkins-and-jmeter)

libraries-data/README.md

@@ -2,3 +2,4 @@
 - [Introduction to Reladomo](http://www.baeldung.com/reladomo)
 - [Introduction to ORMLite](http://www.baeldung.com/ormlite)
 - [Introduction To Kryo](http://www.baeldung.com/kryo)
+- [Introduction to KafkaStreams in Java](http://www.baeldung.com/java-kafka-streams)

libraries/README.md

@@ -58,6 +58,8 @@
 - [Introduction to BouncyCastle with Java](http://www.baeldung.com/java-bouncy-castle)
 - [Intro to JDO Queries 2/2](http://www.baeldung.com/jdo-queries)
 - [Guide to google-http-client](http://www.baeldung.com/google-http-client)
+- [Interact with Google Sheets from Java](http://www.baeldung.com/google-sheets-java-client)
+
 
 
 The libraries module contains examples related to small libraries that are relatively easy to use and does not require any separate module of its own.

libraries/pom.xml

@@ -194,6 +194,11 @@
             <artifactId>jetty-servlet</artifactId>
             <version>${jetty.version}</version>
         </dependency>
+		<dependency>
+		    <groupId>org.eclipse.jetty</groupId>
+		    <artifactId>jetty-webapp</artifactId>
+		   	 <version>${jetty.version}</version>
+		</dependency>
         <dependency>
             <groupId>rome</groupId>
             <artifactId>rome</artifactId>
@@ -741,12 +746,11 @@
         <assertj.version>3.6.2</assertj.version>
         <jsonassert.version>1.5.0</jsonassert.version>
         <javers.version>3.1.0</javers.version>
-        <jetty.version>9.4.3.v20170317</jetty.version>
         <httpclient.version>4.5.3</httpclient.version>
         <commons.io.version>2.5</commons.io.version>
         <commons.dbutils.version>1.6</commons.dbutils.version>
         <h2.version>1.4.196</h2.version>
-        <jetty.version>9.4.2.v20170220</jetty.version>
+        <jetty.version>9.4.8.v20171121</jetty.version>
         <httpclient.version>4.5.3</httpclient.version>
         <commons.io.version>2.5</commons.io.version>
         <flink.version>1.2.0</flink.version>

libraries/src/main/java/com/baeldung/jetty/JettyServerFactory.java

@@ -0,0 +1,94 @@
+package com.baeldung.jetty;
+
+import org.eclipse.jetty.server.Handler;
+import org.eclipse.jetty.server.Server;
+import org.eclipse.jetty.server.ServerConnector;
+import org.eclipse.jetty.server.handler.HandlerCollection;
+import org.eclipse.jetty.webapp.WebAppContext;
+
+/**
+ * Simple factory for creating Jetty basic instances.
+ * 
+ * @author Donato Rimenti
+ *
+ */
+public class JettyServerFactory {
+
+	/**
+	 * Exposed context of the app.
+	 */
+	public final static String APP_PATH = "/myApp";
+	
+	/**
+	 * The server port.
+	 */
+	public final static int SERVER_PORT = 13133;
+
+	/**
+	 * Private constructor to avoid instantiation.
+	 */
+	private JettyServerFactory() {
+	}
+
+	/**
+	 * Returns a simple server listening on port 80 with a timeout of 30 seconds
+	 * for connections and no handlers.
+	 * 
+	 * @return a server
+	 */
+	public static Server createBaseServer() {
+		Server server = new Server();
+
+		// Adds a connector for port 80 with a timeout of 30 seconds.
+		ServerConnector connector = new ServerConnector(server);
+		connector.setPort(SERVER_PORT);
+		connector.setHost("127.0.0.1");
+		connector.setIdleTimeout(30000);
+		server.addConnector(connector);
+
+		return server;
+	}
+
+	/**
+	 * Creates a server which delegates the request handling to a web
+	 * application.
+	 * 
+	 * @return a server
+	 */
+	public static Server createWebAppServer() {
+		// Adds an handler to a server and returns it.
+		Server server = createBaseServer();
+		String webAppFolderPath = JettyServerFactory.class.getClassLoader().getResource("jetty-embedded-demo-app.war")
+				.getPath();
+		Handler webAppHandler = new WebAppContext(webAppFolderPath, APP_PATH);
+		server.setHandler(webAppHandler);
+
+		return server;
+	}
+
+	/**
+	 * Creates a server which delegates the request handling to both a logging
+	 * handler and to a web application, in this order.
+	 * 
+	 * @return a server
+	 */
+	public static Server createMultiHandlerServer() {
+		Server server = createBaseServer();
+
+		// Creates the handlers and adds them to the server.
+		HandlerCollection handlers = new HandlerCollection();
+
+		String webAppFolderPath = JettyServerFactory.class.getClassLoader().getResource("jetty-embedded-demo-app.war")
+				.getPath();
+		Handler customRequestHandler = new WebAppContext(webAppFolderPath, APP_PATH);
+		handlers.addHandler(customRequestHandler);
+
+		Handler loggingRequestHandler = new LoggingRequestHandler();
+		handlers.addHandler(loggingRequestHandler);
+
+		server.setHandler(handlers);
+
+		return server;
+	}
+
+}

libraries/src/main/java/com/baeldung/jetty/LoggingRequestHandler.java

@@ -0,0 +1,168 @@
+package com.baeldung.jetty;
+
+import java.io.IOException;
+
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.eclipse.jetty.server.Handler;
+import org.eclipse.jetty.server.Request;
+import org.eclipse.jetty.server.Server;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Handler implementation which simply logs that a request has been received.
+ * 
+ * @author Donato Rimenti
+ */
+public class LoggingRequestHandler implements Handler {
+
+	/**
+	 * Logger.
+	 */
+	private final static Logger LOG = LoggerFactory.getLogger(LoggingRequestHandler.class);
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.jetty.util.component.LifeCycle#addLifeCycleListener(org.
+	 * eclipse.jetty.util.component.LifeCycle.Listener)
+	 */
+	@Override
+	public void addLifeCycleListener(Listener arg0) {
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.jetty.util.component.LifeCycle#isFailed()
+	 */
+	@Override
+	public boolean isFailed() {
+		return false;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.jetty.util.component.LifeCycle#isRunning()
+	 */
+	@Override
+	public boolean isRunning() {
+		return true;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.jetty.util.component.LifeCycle#isStarted()
+	 */
+	@Override
+	public boolean isStarted() {
+		return true;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.jetty.util.component.LifeCycle#isStarting()
+	 */
+	@Override
+	public boolean isStarting() {
+		return false;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.jetty.util.component.LifeCycle#isStopped()
+	 */
+	@Override
+	public boolean isStopped() {
+		return false;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.jetty.util.component.LifeCycle#isStopping()
+	 */
+	@Override
+	public boolean isStopping() {
+		return false;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see
+	 * org.eclipse.jetty.util.component.LifeCycle#removeLifeCycleListener(org.
+	 * eclipse.jetty.util.component.LifeCycle.Listener)
+	 */
+	@Override
+	public void removeLifeCycleListener(Listener arg0) {
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.jetty.util.component.LifeCycle#start()
+	 */
+	@Override
+	public void start() throws Exception {
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.jetty.util.component.LifeCycle#stop()
+	 */
+	@Override
+	public void stop() throws Exception {
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.jetty.server.Handler#destroy()
+	 */
+	@Override
+	public void destroy() {
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.jetty.server.Handler#getServer()
+	 */
+	@Override
+	public Server getServer() {
+		return null;
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.jetty.server.Handler#handle(java.lang.String,
+	 * org.eclipse.jetty.server.Request, javax.servlet.http.HttpServletRequest,
+	 * javax.servlet.http.HttpServletResponse)
+	 */
+	@Override
+	public void handle(String arg0, Request arg1, HttpServletRequest arg2, HttpServletResponse arg3)
+			throws IOException, ServletException {
+		LOG.info("Received a new request");
+	}
+
+	/*
+	 * (non-Javadoc)
+	 * 
+	 * @see org.eclipse.jetty.server.Handler#setServer(org.eclipse.jetty.server.
+	 * Server)
+	 */
+	@Override
+	public void setServer(Server server) {
+	}
+
+}

libraries/src/main/java/com/baeldung/netty/ChannelHandlerA.java

@@ -0,0 +1,22 @@
+package com.baeldung.netty;
+
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelInboundHandlerAdapter;
+
+import java.util.logging.Logger;
+
+public class ChannelHandlerA extends ChannelInboundHandlerAdapter {
+
+    private Logger logger = Logger.getLogger(getClass().getName());
+
+    @Override
+    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
+        throw new Exception("Ooops");
+    }
+
+    @Override
+    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
+        logger.info("Exception Occurred in ChannelHandler A");
+        ctx.fireExceptionCaught(cause);
+    }
+}

libraries/src/main/java/com/baeldung/netty/ChannelHandlerB.java

@@ -0,0 +1,20 @@
+package com.baeldung.netty;
+
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelInboundHandlerAdapter;
+
+import java.util.logging.Logger;
+
+
+public class ChannelHandlerB extends ChannelInboundHandlerAdapter {
+
+    private Logger logger = Logger.getLogger(getClass().getName());
+
+    @Override
+    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
+        logger.info("Exception Handled in ChannelHandler B");
+        logger.info(cause.getLocalizedMessage());
+        //do more exception handling
+        ctx.close();
+    }
+}

libraries/src/main/java/com/baeldung/netty/NettyServerB.java

@@ -0,0 +1,47 @@
+package com.baeldung.netty;
+
+import io.netty.bootstrap.ServerBootstrap;
+import io.netty.channel.ChannelFuture;
+import io.netty.channel.ChannelInitializer;
+import io.netty.channel.ChannelOption;
+import io.netty.channel.EventLoopGroup;
+import io.netty.channel.nio.NioEventLoopGroup;
+import io.netty.channel.socket.SocketChannel;
+import io.netty.channel.socket.nio.NioServerSocketChannel;
+
+public class NettyServerB  {
+
+    private int port;
+
+    private NettyServerB(int port) {
+        this.port = port;
+    }
+
+    private void run() throws Exception {
+
+        EventLoopGroup bossGroup = new NioEventLoopGroup();
+        EventLoopGroup workerGroup = new NioEventLoopGroup();
+
+        try {
+            ServerBootstrap b = new ServerBootstrap();
+            b.group(bossGroup, workerGroup)
+                .channel(NioServerSocketChannel.class)
+                .childHandler(new ChannelInitializer<SocketChannel>() {
+                    public void initChannel(SocketChannel ch) throws Exception {
+                        ch.pipeline().addLast(new ChannelHandlerA(), new ChannelHandlerB());
+                    }
+                })
+                .option(ChannelOption.SO_BACKLOG, 128)
+                .childOption(ChannelOption.SO_KEEPALIVE, true);
+            ChannelFuture f = b.bind(port).sync(); // (7)
+            f.channel().closeFuture().sync();
+        } finally {
+            workerGroup.shutdownGracefully();
+            bossGroup.shutdownGracefully();
+        }
+    }
+
+    public static void main(String[] args) throws Exception {
+        new NettyServerB(8080).run();
+    }
+}

libraries/src/test/java/com/baeldung/jetty/JettyServerFactoryUnitTest.java

@@ -0,0 +1,86 @@
+package com.baeldung.jetty;
+
+import org.apache.http.HttpHost;
+import org.apache.http.HttpRequest;
+import org.apache.http.HttpResponse;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.impl.client.HttpClientBuilder;
+import org.eclipse.jetty.server.Server;
+import org.junit.Assert;
+import org.junit.Test;
+
+/**
+ * Test for {@link JettyServerFactory}.
+ * 
+ * @author Donato Rimenti
+ *
+ */
+public class JettyServerFactoryUnitTest {
+
+	/**
+	 * Tests that when a base server is provided a request returns a status 404.
+	 * 
+	 * @throws Exception
+	 */
+	@Test
+	public void givenBaseServer_whenHttpRequest_thenStatus404() throws Exception {
+		Server server = JettyServerFactory.createBaseServer();
+		server.start();
+		
+		int statusCode = sendGetRequest();
+		
+		Assert.assertEquals(404, statusCode);
+		server.stop();
+	}
+
+	/**
+	 * Tests that when a web app server is provided a request returns a status
+	 * 200.
+	 * 
+	 * @throws Exception
+	 */
+	@Test
+	public void givenWebAppServer_whenHttpRequest_thenStatus200() throws Exception {
+		Server server = JettyServerFactory.createWebAppServer();
+		server.start();
+
+		int statusCode = sendGetRequest();
+		
+		Assert.assertEquals(200, statusCode);
+		server.stop();
+	}
+
+	/**
+	 * Tests that when a multi handler server is provided a request returns a
+	 * status 200.
+	 * 
+	 * @throws Exception
+	 */
+	@Test
+	public void givenMultiHandlerServerServer_whenHttpRequest_thenStatus200() throws Exception {
+		Server server = JettyServerFactory.createMultiHandlerServer();
+		server.start();
+
+		int statusCode = sendGetRequest();
+		
+		Assert.assertEquals(200, statusCode);
+		server.stop();
+	}
+
+	/**
+	 * Sends a default HTTP GET request to the server and returns the response
+	 * status code.
+	 * 
+	 * @return the status code of the response
+	 * @throws Exception
+	 */
+	private int sendGetRequest() throws Exception {
+		HttpHost target = new HttpHost("localhost", JettyServerFactory.SERVER_PORT);
+		HttpRequest request = new HttpGet(JettyServerFactory.APP_PATH);
+		HttpClient client = HttpClientBuilder.create().build();
+		HttpResponse response = client.execute(target, request);
+		return response.getStatusLine().getStatusCode();
+	}
+
+}

libraries/src/test/java/com/baeldung/pact/PactConsumerDrivenContractUnitTest.java

@@ -32,9 +32,9 @@ public class PactConsumerDrivenContractUnitTest {
         headers.put("Content-Type", "application/json");
 
         return builder
-          .given("test GET ")
+          .given("test GET")
           .uponReceiving("GET REQUEST")
-          .path("/")
+          .path("/pact")
           .method("GET")
           .willRespondWith()
           .status(200)
@@ -45,11 +45,9 @@ public class PactConsumerDrivenContractUnitTest {
           .method("POST")
           .headers(headers)
           .body("{\"name\": \"Michael\"}")
-          .path("/create")
+          .path("/pact")
           .willRespondWith()
           .status(201)
-          .headers(headers)
-          .body("")
           .toPact();
     }
 
@@ -59,7 +57,7 @@ public class PactConsumerDrivenContractUnitTest {
     public void givenGet_whenSendRequest_shouldReturn200WithProperHeaderAndBody() {
         //when
         ResponseEntity<String> response
-          = new RestTemplate().getForEntity(mockProvider.getUrl(), String.class);
+          = new RestTemplate().getForEntity(mockProvider.getUrl() + "/pact", String.class);
 
         //then
         assertThat(response.getStatusCode().value()).isEqualTo(200);
@@ -73,7 +71,7 @@ public class PactConsumerDrivenContractUnitTest {
 
         //when
         ResponseEntity<String> postResponse = new RestTemplate().exchange(
-          mockProvider.getUrl() + "/create",
+          mockProvider.getUrl() + "/pact",
           HttpMethod.POST,
           new HttpEntity<>(jsonBody, httpHeaders),
           String.class

logging-modules/README.md

@@ -1,3 +1,6 @@
 
 ## Logging Modules
 
+### Relevant Articles:
+
+- [Creating a Custom Logback Appender](http://www.baeldung.com/custom-logback-appender)

logging-modules/log4j2/pom.xml

@@ -59,10 +59,10 @@
 
 
     <properties>
-        <jackson.version>2.8.5</jackson.version>
+        <jackson.version>2.9.3</jackson.version>
         <h2.version>1.4.193</h2.version>
         <commons-dbcp2.version>2.1.1</commons-dbcp2.version>
-        <log4j-core.version>2.7</log4j-core.version>
+        <log4j-core.version>2.10.0</log4j-core.version>
     </properties>
 
 </project>

logging-modules/log4j2/src/test/java/com/baeldung/logging/log4j2/tests/JSONLayoutTest.java

@@ -0,0 +1,45 @@
+package com.baeldung.logging.log4j2.tests;
+
+import static org.junit.Assert.assertTrue;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.PrintStream;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.junit.Before;
+import org.junit.Test;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+public class JSONLayoutTest {
+
+    private static Logger logger;
+    private ByteArrayOutputStream consoleOutput = new ByteArrayOutputStream();
+    private PrintStream ps = new PrintStream(consoleOutput);
+
+    @Before
+    public void setUp() {
+        // Redirect console output to our stream
+        System.setOut(ps);
+        logger = LogManager.getLogger("CONSOLE_JSON_APPENDER");
+    }
+
+    @Test
+    public void whenLogLayoutInJSON_thenOutputIsCorrectJSON() {
+        logger.debug("Debug message");
+        String currentLog = consoleOutput.toString();
+        assertTrue(!currentLog.isEmpty() && isValidJSON(currentLog));
+    }
+
+    public static boolean isValidJSON(String jsonInString) {
+        try {
+            final ObjectMapper mapper = new ObjectMapper();
+            mapper.readTree(jsonInString);
+            return true;
+        } catch (IOException e) {
+            return false;
+        }
+    }
+}

logging-modules/log4j2/src/test/resources/log4j2.xml

@@ -1,16 +1,25 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<Configuration xmlns:xi="http://www.w3.org/2001/XInclude" status="WARN">
+<Configuration xmlns:xi="http://www.w3.org/2001/XInclude"
+    status="WARN">
     <Appenders>
-        <xi:include href="log4j2-includes/console-appender_pattern-layout_colored.xml" />
+        <xi:include
+            href="log4j2-includes/console-appender_pattern-layout_colored.xml" />
         <Console name="ConsoleAppender" target="SYSTEM_OUT">
-            <PatternLayout pattern="%d [%t] %-5level %logger{36} - %msg%n%throwable" />
+            <PatternLayout
+                pattern="%d [%t] %-5level %logger{36} - %msg%n%throwable" />
         </Console>
         <Console name="ConsoleRedAppender" target="SYSTEM_OUT">
             <PatternLayout pattern="%style{%message}{red}%n" />
             <MarkerFilter marker="CONN_TRACE" />
         </Console>
         <Console name="ConsoleGreenAppender" target="SYSTEM_OUT">
-            <PatternLayout pattern="%style{userId=%X{userId}:}{white} %style{%message}{green}%n" />
+            <PatternLayout
+                pattern="%style{userId=%X{userId}:}{white} %style{%message}{green}%n" />
+        </Console>
+        <Console name="ConsoleJSONAppender" target="SYSTEM_OUT">
+            <JsonLayout complete="false" compact="false">
+                <KeyValuePair key="myCustomField" value="myCustomValue" />
+            </JsonLayout>
         </Console>
         <File name="JSONLogfileAppender" fileName="target/logfile.json">
             <JSONLayout compact="true" eventEol="true" />
@@ -19,53 +28,58 @@
         <Async name="AsyncAppender" bufferSize="80">
             <AppenderRef ref="JSONLogfileAppender" />
         </Async>
-<!--
-        <Syslog name="Syslog" format="RFC5424" host="localhost" port="514" protocol="TCP" facility="local3" connectTimeoutMillis="10000" reconnectionDelayMillis="5000" mdcId="mdc" includeMDC="true" />
-        <Failover name="FailoverAppender" primary="Syslog">
-            <Failovers>
-                <AppenderRef ref="ConsoleAppender" />
-            </Failovers>
-        </Failover>
--->
+        <!-- <Syslog name="Syslog" format="RFC5424" host="localhost" port="514" 
+            protocol="TCP" facility="local3" connectTimeoutMillis="10000" reconnectionDelayMillis="5000" 
+            mdcId="mdc" includeMDC="true" /> <Failover name="FailoverAppender" primary="Syslog"> 
+            <Failovers> <AppenderRef ref="ConsoleAppender" /> </Failovers> </Failover> -->
         <JDBC name="JDBCAppender" tableName="logs">
-            <ConnectionFactory class="com.baeldung.logging.log4j2.tests.jdbc.ConnectionFactory" method="getConnection" />
+            <ConnectionFactory
+                class="com.baeldung.logging.log4j2.tests.jdbc.ConnectionFactory"
+                method="getConnection" />
             <Column name="when" isEventTimestamp="true" />
             <Column name="logger" pattern="%logger" />
             <Column name="level" pattern="%level" />
             <Column name="message" pattern="%message" />
             <Column name="throwable" pattern="%ex{full}" />
         </JDBC>
-        <RollingFile name="XMLRollingfileAppender" fileName="target/logfile.xml" filePattern="target/logfile-%d{yyyy-MM-dd}-%i.log.gz">
+        <RollingFile name="XMLRollingfileAppender" fileName="target/logfile.xml"
+            filePattern="target/logfile-%d{yyyy-MM-dd}-%i.log.gz">
             <XMLLayout />
             <Policies>
-                <SizeBasedTriggeringPolicy size="17 kB" />
+                <SizeBasedTriggeringPolicy
+                    size="17 kB" />
             </Policies>
         </RollingFile>
     </Appenders>
     <Loggers>
-        <Logger name="CONSOLE_PATTERN_APPENDER_MARKER" level="TRACE" additivity="false">
+        <Logger name="CONSOLE_PATTERN_APPENDER_MARKER" level="TRACE"
+            additivity="false">
             <AppenderRef ref="ConsoleRedAppender" />
         </Logger>
-        <Logger name="CONSOLE_PATTERN_APPENDER_THREAD_CONTEXT" level="INFO" additivity="false">
+        <Logger name="CONSOLE_PATTERN_APPENDER_THREAD_CONTEXT"
+            level="INFO" additivity="false">
             <AppenderRef ref="ConsoleGreenAppender" />
             <ThreadContextMapFilter>
                 <KeyValuePair key="userId" value="1000" />
             </ThreadContextMapFilter>
         </Logger>
-        <Logger name="ASYNC_JSON_FILE_APPENDER" level="INFO" additivity="false">
+        <Logger name="ASYNC_JSON_FILE_APPENDER" level="INFO"
+            additivity="false">
             <AppenderRef ref="AsyncAppender" />
         </Logger>
-<!--
-        <Logger name="FAIL_OVER_SYSLOG_APPENDER" level="INFO" additivity="false">
-            <AppenderRef ref="FailoverAppender" />
-        </Logger>
--->
+        <!-- <Logger name="FAIL_OVER_SYSLOG_APPENDER" level="INFO" additivity="false"> 
+            <AppenderRef ref="FailoverAppender" /> </Logger> -->
         <Logger name="JDBC_APPENDER" level="INFO" additivity="false">
             <AppenderRef ref="JDBCAppender" />
         </Logger>
-        <Logger name="XML_ROLLING_FILE_APPENDER" level="INFO" additivity="false">
+        <Logger name="XML_ROLLING_FILE_APPENDER" level="INFO"
+            additivity="false">
             <AppenderRef ref="XMLRollingfileAppender" />
         </Logger>
+        <Logger name="CONSOLE_JSON_APPENDER" level="TRACE"
+            additivity="false">
+            <AppenderRef ref="ConsoleJSONAppender" />
+        </Logger>
         <Root level="DEBUG">
             <AppenderRef ref="ConsoleAppender" />
         </Root>

logging-modules/logback/pom.xml

@@ -1,6 +1,6 @@
 <?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
+    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>
@@ -12,6 +12,8 @@
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <logback.version>1.2.3</logback.version>
+        <logback.contrib.version>0.1.5</logback.contrib.version>
+        <jackson.version>2.9.3</jackson.version>
     </properties>
 
     <parent>
@@ -28,7 +30,21 @@
             <artifactId>logback-classic</artifactId>
             <version>${logback.version}</version>
         </dependency>
-
+        <dependency>
+            <groupId>ch.qos.logback.contrib</groupId>
+            <artifactId>logback-json-classic</artifactId>
+            <version>${logback.contrib.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>ch.qos.logback.contrib</groupId>
+            <artifactId>logback-jackson</artifactId>
+            <version>${logback.contrib.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+            <version>${jackson.version}</version>
+        </dependency>
     </dependencies>
 
 

logging-modules/logback/src/test/java/com/baeldung/logback/JSONLayoutTest.java

@@ -0,0 +1,45 @@
+package com.baeldung.logback;
+
+import static org.junit.Assert.assertTrue;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.PrintStream;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+
+public class JSONLayoutTest {
+
+    private static Logger logger;
+    private ByteArrayOutputStream consoleOutput = new ByteArrayOutputStream();
+    private PrintStream ps = new PrintStream(consoleOutput);
+
+    @Before
+    public void setUp() {
+        // Redirect console output to our stream
+        System.setOut(ps);
+        logger = LoggerFactory.getLogger("jsonLogger");
+    }
+
+    @Test
+    public void whenLogLayoutInJSON_thenOutputIsCorrectJSON() {
+        logger.debug("Debug message");
+        String currentLog = consoleOutput.toString();
+        assertTrue(!currentLog.isEmpty() && isValidJSON(currentLog));
+    }
+
+    public static boolean isValidJSON(String jsonInString) {
+        try {
+            final ObjectMapper mapper = new ObjectMapper();
+            mapper.readTree(jsonInString);
+            return true;
+        } catch (IOException e) {
+            return false;
+        }
+    }
+}

logging-modules/logback/src/test/resources/logback-test.xml

@@ -1,14 +1,31 @@
-<configuration debug="true">
+<configuration debug="false">
+
+    <statusListener class="ch.qos.logback.core.status.NopStatusListener" />
 
     <appender name="map" class="com.baeldung.logback.MapAppender">
         <prefix>test</prefix>
     </appender>
 
-    <appender name="badMap" class="com.baeldung.logback.MapAppender"/>
+    <appender name="badMap" class="com.baeldung.logback.MapAppender" />
+
+    # JSON appender
+    <appender name="json" class="ch.qos.logback.core.ConsoleAppender">
+        <layout class="ch.qos.logback.contrib.json.classic.JsonLayout">
+            <jsonFormatter
+                class="ch.qos.logback.contrib.jackson.JacksonJsonFormatter">
+                <prettyPrint>true</prettyPrint>
+            </jsonFormatter>
+            <timestampFormat>yyyy-MM-dd' 'HH:mm:ss.SSS</timestampFormat>
+        </layout>
+    </appender>
+
+    <logger name="jsonLogger" level="TRACE">
+        <appender-ref ref="json" />
+    </logger>
 
     <root level="debug">
-        <appender-ref ref="map"/>
-        <appender-ref ref="badMap"/>
+        <appender-ref ref="map" />
+        <appender-ref ref="badMap" />
     </root>
 
 </configuration>

lucene/README.md

@@ -0,0 +1,4 @@
+### Relevant Articles:
+
+- [Introduction to Apache Lucene](http://www.baeldung.com/lucene)
+- [A Simple File Search with Lucene](http://www.baeldung.com/lucene-file-search)

muleesb/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [Getting Started With Mule ESB](http://www.baeldung.com/mule-esb)

orientdb/README.md

@@ -22,4 +22,7 @@ $ mvn clean install
 Before launching unit tests:
 - Install OrientDB
 - Create BaeldungDB, BaeldungDBTwo and BaeldungDBThree databases
-- Uncomment annotations on the test files
+- Uncomment annotations on the test files
+
+### Relevant Articles:
+- [Introduction to the OrientDB Java APIs](http://www.baeldung.com/java-orientdb)

persistence-modules/README.md

@@ -1,3 +1,7 @@
 
 ## Persistence Modules
 
+
+### Relevant Articles:
+
+- [Introduction to Hibernate Search](http://www.baeldung.com/hibernate-search)

pom.xml

@@ -113,7 +113,9 @@
         <module>lombok</module>
        <!-- <module>kotlin</module>-->
         <module>mapstruct</module>
+	<!--
         <module>metrics</module>
+        -->
         <module>mesos-marathon</module>
         <module>testing-modules/mockito</module>
         <module>testing-modules/mockito-2</module>

spring-5-reactive/pom.xml

@@ -60,7 +60,13 @@
         <!-- <version>1.1.2</version> -->
         <!-- </dependency> -->
         <!-- Dependencies for Johnzon -->
-        
+        <!-- lombok-->
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<scope>compile</scope>
+		</dependency>
+		
         <dependency>
             <groupId>org.apache.geronimo.specs</groupId>
             <artifactId>geronimo-json_1.1_spec</artifactId>

spring-5-reactive/src/main/java/com/baeldung/reactive/websocket/Event.java

@@ -1,4 +1,4 @@
-package com.baeldung;
+package com.baeldung.reactive.websocket;
 
 import lombok.AllArgsConstructor;
 import lombok.Data;

spring-5-reactive/src/main/java/com/baeldung/reactive/websocket/ReactiveJavaClientWebSocket.java

@@ -0,0 +1,23 @@
+package com.baeldung.reactive.websocket;
+
+import java.net.URI;
+import java.time.Duration;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.web.reactive.socket.WebSocketMessage;
+import org.springframework.web.reactive.socket.client.ReactorNettyWebSocketClient;
+import org.springframework.web.reactive.socket.client.WebSocketClient;
+
+import reactor.core.publisher.Mono;
+
+@SpringBootApplication
+public class ReactiveJavaClientWebSocket {
+    public static void main(String[] args) throws InterruptedException {
+        WebSocketClient client = new ReactorNettyWebSocketClient();
+        client.execute(URI.create("ws://localhost:8080/event-emitter"), session ->  session.send(Mono.just(session.textMessage("event-me-from-spring-reactive-client")))
+            .thenMany(session.receive()
+                .map(WebSocketMessage::getPayloadAsText)
+                .log())
+            .then())
+            .block(Duration.ofSeconds(10L));
+    }
+}

spring-5-reactive/src/main/java/com/baeldung/reactive/websocket/ReactiveWebSocketApplication.java

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

spring-5-reactive/src/main/java/com/baeldung/reactive/websocket/ReactiveWebSocketConfiguration.java

@@ -1,4 +1,4 @@
-package com.baeldung;
+package com.baeldung.reactive.websocket;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Bean;

spring-5-reactive/src/main/java/com/baeldung/reactive/websocket/ReactiveWebSocketHandler.java

@@ -1,4 +1,4 @@
-package com.baeldung;
+package com.baeldung.reactive.websocket;
 
 import org.springframework.web.reactive.socket.WebSocketSession;
 

spring-5-security/pom.xml

@@ -30,6 +30,10 @@
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-thymeleaf</artifactId>
 		</dependency>
+		<dependency>
+			<groupId>org.thymeleaf.extras</groupId>
+			<artifactId>thymeleaf-extras-springsecurity4</artifactId>
+		</dependency>
 
 		<!-- oauth2 -->
 		<dependency>
@@ -40,6 +44,21 @@
 			<groupId>org.springframework.security</groupId>
 			<artifactId>spring-security-oauth2-jose</artifactId>
 		</dependency>
+
+		<dependency>
+			<groupId>org.springframework</groupId>
+			<artifactId>spring-test</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.security</groupId>
+			<artifactId>spring-security-test</artifactId>
+			<scope>test</scope>
+		</dependency>
 	</dependencies>
 
 	<build>

spring-5-security/src/main/java/com/baeldung/loginextrafieldscustom/CustomAuthenticationFilter.java

@@ -0,0 +1,50 @@
+package com.baeldung.loginextrafieldscustom;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.springframework.security.authentication.AuthenticationServiceException;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.AuthenticationException;
+import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
+
+public class CustomAuthenticationFilter extends UsernamePasswordAuthenticationFilter {
+
+    public static final String SPRING_SECURITY_FORM_DOMAIN_KEY = "domain";
+
+    @Override
+    public Authentication attemptAuthentication(HttpServletRequest request, HttpServletResponse response) 
+        throws AuthenticationException {
+
+        if (!request.getMethod().equals("POST")) {
+            throw new AuthenticationServiceException("Authentication method not supported: " 
+              + request.getMethod());
+        }
+
+        CustomAuthenticationToken authRequest = getAuthRequest(request);
+        setDetails(request, authRequest);
+        return this.getAuthenticationManager().authenticate(authRequest);
+    }
+
+    private CustomAuthenticationToken getAuthRequest(HttpServletRequest request) {
+        String username = obtainUsername(request);
+        String password = obtainPassword(request);
+        String domain = obtainDomain(request);
+
+        if (username == null) {
+            username = "";
+        }
+        if (password == null) {
+            password = "";
+        }
+        if (domain == null) {
+            domain = "";
+        }
+
+        return new CustomAuthenticationToken(username, password, domain);
+    }
+
+    private String obtainDomain(HttpServletRequest request) {
+        return request.getParameter(SPRING_SECURITY_FORM_DOMAIN_KEY);
+    }
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldscustom/CustomAuthenticationToken.java

@@ -0,0 +1,28 @@
+package com.baeldung.loginextrafieldscustom;
+
+import java.util.Collection;
+
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.GrantedAuthority;
+
+public class CustomAuthenticationToken extends UsernamePasswordAuthenticationToken {
+
+    private String domain;
+
+    public CustomAuthenticationToken(Object principal, Object credentials, String domain) {
+        super(principal, credentials);
+        this.domain = domain;
+        super.setAuthenticated(false);
+    }
+
+    public CustomAuthenticationToken(Object principal, Object credentials, String domain, 
+        Collection<? extends GrantedAuthority> authorities) {
+        super(principal, credentials, authorities);
+        this.domain = domain;
+        super.setAuthenticated(true); // must use super, as we override
+    }
+
+    public String getDomain() {
+        return this.domain;
+    }
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldscustom/CustomUserDetailsAuthenticationProvider.java

@@ -0,0 +1,92 @@
+package com.baeldung.loginextrafieldscustom;
+
+import org.springframework.security.authentication.BadCredentialsException;
+import org.springframework.security.authentication.InternalAuthenticationServiceException;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.authentication.dao.AbstractUserDetailsAuthenticationProvider;
+import org.springframework.security.core.AuthenticationException;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.util.Assert;
+
+public class CustomUserDetailsAuthenticationProvider extends AbstractUserDetailsAuthenticationProvider {
+
+    /**
+     * The plaintext password used to perform
+     * PasswordEncoder#matches(CharSequence, String)}  on when the user is
+     * not found to avoid SEC-2056.
+     */
+    private static final String USER_NOT_FOUND_PASSWORD = "userNotFoundPassword";
+
+    private PasswordEncoder passwordEncoder;
+    private CustomUserDetailsService userDetailsService;
+
+    /**
+     * The password used to perform
+     * {@link PasswordEncoder#matches(CharSequence, String)} on when the user is
+     * not found to avoid SEC-2056. This is necessary, because some
+     * {@link PasswordEncoder} implementations will short circuit if the password is not
+     * in a valid format.
+     */
+    private String userNotFoundEncodedPassword;
+
+    public CustomUserDetailsAuthenticationProvider(PasswordEncoder passwordEncoder, CustomUserDetailsService userDetailsService) {
+        this.passwordEncoder = passwordEncoder;
+        this.userDetailsService = userDetailsService;
+    }
+
+    @Override
+    protected void additionalAuthenticationChecks(UserDetails userDetails, UsernamePasswordAuthenticationToken authentication) 
+        throws AuthenticationException {
+
+        if (authentication.getCredentials() == null) {
+            logger.debug("Authentication failed: no credentials provided");
+            throw new BadCredentialsException(
+                messages.getMessage("AbstractUserDetailsAuthenticationProvider.badCredentials", "Bad credentials"));
+        }
+
+        String presentedPassword = authentication.getCredentials()
+            .toString();
+
+        if (!passwordEncoder.matches(presentedPassword, userDetails.getPassword())) {
+            logger.debug("Authentication failed: password does not match stored value");
+            throw new BadCredentialsException(
+                messages.getMessage("AbstractUserDetailsAuthenticationProvider.badCredentials", "Bad credentials"));
+        }
+    }
+
+    @Override
+    protected void doAfterPropertiesSet() throws Exception {
+        Assert.notNull(this.userDetailsService, "A UserDetailsService must be set");
+        this.userNotFoundEncodedPassword = this.passwordEncoder.encode(USER_NOT_FOUND_PASSWORD);
+    }
+
+    @Override
+    protected UserDetails retrieveUser(String username, UsernamePasswordAuthenticationToken authentication) 
+        throws AuthenticationException {
+        CustomAuthenticationToken auth = (CustomAuthenticationToken) authentication;
+        UserDetails loadedUser;
+
+        try {
+            loadedUser = this.userDetailsService.loadUserByUsernameAndDomain(auth.getPrincipal()
+                .toString(), auth.getDomain());
+        } catch (UsernameNotFoundException notFound) {
+            if (authentication.getCredentials() != null) {
+                String presentedPassword = authentication.getCredentials()
+                    .toString();
+                passwordEncoder.matches(presentedPassword, userNotFoundEncodedPassword);
+            }
+            throw notFound;
+        } catch (Exception repositoryProblem) {
+            throw new InternalAuthenticationServiceException(repositoryProblem.getMessage(), repositoryProblem);
+        }
+
+        if (loadedUser == null) {
+            throw new InternalAuthenticationServiceException("UserDetailsService returned null, "
+                + "which is an interface contract violation");
+        }
+        return loadedUser;
+    }
+
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldscustom/CustomUserDetailsService.java

@@ -0,0 +1,10 @@
+package com.baeldung.loginextrafieldscustom;
+
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
+
+public interface CustomUserDetailsService {
+
+    UserDetails loadUserByUsernameAndDomain(String username, String domain) throws UsernameNotFoundException;
+
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldscustom/CustomUserDetailsServiceImpl.java

@@ -0,0 +1,30 @@
+package com.baeldung.loginextrafieldscustom;
+
+import org.apache.commons.lang3.StringUtils;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
+import org.springframework.stereotype.Service;
+
+@Service("userDetailsService")
+public class CustomUserDetailsServiceImpl implements CustomUserDetailsService {
+
+    private UserRepository userRepository;
+ 
+    public CustomUserDetailsServiceImpl(UserRepository userRepository) {
+        this.userRepository = userRepository;
+    }
+
+    @Override
+    public UserDetails loadUserByUsernameAndDomain(String username, String domain) throws UsernameNotFoundException {
+        if (StringUtils.isAnyBlank(username, domain)) {
+            throw new UsernameNotFoundException("Username and domain must be provided");
+        }
+        User user = userRepository.findUser(username, domain);
+        if (user == null) {
+            throw new UsernameNotFoundException(
+                String.format("Username not found for domain, username=%s, domain=%s", 
+                    username, domain));
+        }
+        return user;
+    }
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldscustom/CustomUserRepository.java

@@ -0,0 +1,26 @@
+package com.baeldung.loginextrafieldscustom;
+
+import java.util.ArrayList;
+import java.util.Collection;
+
+import org.apache.commons.lang3.StringUtils;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.stereotype.Repository;
+
+@Repository("userRepository")
+public class CustomUserRepository implements UserRepository {
+
+    @Override
+    public User findUser(String username, String domain) {
+        if (StringUtils.isAnyBlank(username, domain)) {
+            return null;
+        } else {
+            Collection<? extends GrantedAuthority> authorities = new ArrayList<>();
+            User user =  new User(username, domain, 
+                "$2a$10$U3GhSMpsMSOE8Kqsbn58/edxDBKlVuYMh7qk/7ErApYFjJzi2VG5K", true, 
+                true, true, true, authorities);
+            return user;
+        }
+    }
+
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldscustom/ExtraLoginFieldsApplication.java

@@ -0,0 +1,13 @@
+package com.baeldung.loginextrafieldscustom;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class ExtraLoginFieldsApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(ExtraLoginFieldsApplication.class, args);
+    }
+
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldscustom/SecurityConfig.java

@@ -0,0 +1,62 @@
+package com.baeldung.loginextrafieldscustom;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.PropertySource;
+import org.springframework.security.authentication.AuthenticationProvider;
+import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
+import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
+import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.security.web.authentication.SimpleUrlAuthenticationFailureHandler;
+import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
+
+@EnableWebSecurity
+@PropertySource("classpath:/application-extrafields.properties")
+public class SecurityConfig extends WebSecurityConfigurerAdapter {
+
+    @Autowired
+    private CustomUserDetailsService userDetailsService;
+
+    @Override
+    protected void configure(HttpSecurity http) throws Exception {
+        
+        http
+            .addFilterBefore(authenticationFilter(), UsernamePasswordAuthenticationFilter.class)
+            .authorizeRequests()
+                .antMatchers("/css/**", "/index").permitAll()
+                .antMatchers("/user/**").authenticated()
+            .and()
+            .formLogin().loginPage("/login")
+            .and()
+            .logout()
+            .logoutUrl("/logout");
+    }
+
+    public CustomAuthenticationFilter authenticationFilter() throws Exception {
+        CustomAuthenticationFilter filter = new CustomAuthenticationFilter();
+        filter.setAuthenticationManager(authenticationManagerBean());
+        filter.setAuthenticationFailureHandler(failureHandler());
+        return filter;
+    }
+
+    @Autowired
+    public void configureGlobal(AuthenticationManagerBuilder auth) throws Exception {
+        auth.authenticationProvider(authProvider());
+    }
+
+    public AuthenticationProvider authProvider() {
+        CustomUserDetailsAuthenticationProvider provider 
+            = new CustomUserDetailsAuthenticationProvider(passwordEncoder(), userDetailsService);
+        return provider;
+    }
+
+    public SimpleUrlAuthenticationFailureHandler failureHandler() {
+        return new SimpleUrlAuthenticationFailureHandler("/login?error=true");
+    }
+
+    public PasswordEncoder passwordEncoder() {
+        return new BCryptPasswordEncoder();
+    }
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldscustom/User.java

@@ -0,0 +1,23 @@
+package com.baeldung.loginextrafieldscustom;
+
+import java.util.Collection;
+
+import org.springframework.security.core.GrantedAuthority;
+
+public class User extends org.springframework.security.core.userdetails.User {
+
+    private static final long serialVersionUID = 1L;
+
+    private String domain;
+
+    public User(String username, String domain, String password, boolean enabled, 
+        boolean accountNonExpired, boolean credentialsNonExpired, 
+        boolean accountNonLocked, Collection<? extends GrantedAuthority> authorities) {
+        super(username, password, enabled, accountNonExpired, credentialsNonExpired, accountNonLocked, authorities);
+        this.domain = domain;
+    }
+
+    public String getDomain() {
+        return domain;
+    }
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldscustom/UserRepository.java

@@ -0,0 +1,7 @@
+package com.baeldung.loginextrafieldscustom;
+
+public interface UserRepository {
+
+    public User findUser(String username, String domain);
+    
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldscustom/WebController.java

@@ -0,0 +1,51 @@
+package com.baeldung.loginextrafieldscustom;
+
+import java.util.Optional;
+
+import org.springframework.security.authentication.AnonymousAuthenticationToken;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.RequestMapping;
+
+@Controller
+public class WebController {
+
+    @RequestMapping("/")
+    public String root() {
+        return "redirect:/index";
+    }
+
+    @RequestMapping("/index")
+    public String index(Model model) {
+        getDomain().ifPresent(d -> {
+            model.addAttribute("domain", d);
+        });
+        return "index";
+    }
+
+    @RequestMapping("/user/index")
+    public String userIndex(Model model) {
+        getDomain().ifPresent(d -> {
+            model.addAttribute("domain", d);
+        });
+        return "user/index";
+    }
+
+    @RequestMapping("/login")
+    public String login() {
+        return "login";
+    }
+
+    private Optional<String> getDomain() {
+        Authentication auth = SecurityContextHolder.getContext()
+            .getAuthentication(); 
+        String domain = null;
+        if (auth != null && !auth.getClass().equals(AnonymousAuthenticationToken.class)) {
+            User user = (User) auth.getPrincipal();
+            domain = user.getDomain();
+        }
+        return Optional.ofNullable(domain);
+    }
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldssimple/ExtraLoginFieldsApplication.java

@@ -0,0 +1,13 @@
+package com.baeldung.loginextrafieldssimple;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class ExtraLoginFieldsApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(ExtraLoginFieldsApplication.class, args);
+    }
+
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldssimple/SecurityConfig.java

@@ -0,0 +1,65 @@
+package com.baeldung.loginextrafieldssimple;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.PropertySource;
+import org.springframework.security.authentication.AuthenticationProvider;
+import org.springframework.security.authentication.dao.DaoAuthenticationProvider;
+import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
+import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
+import org.springframework.security.core.userdetails.UserDetailsService;
+import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.security.web.authentication.SimpleUrlAuthenticationFailureHandler;
+import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
+
+@EnableWebSecurity
+@PropertySource("classpath:/application-extrafields.properties")
+public class SecurityConfig extends WebSecurityConfigurerAdapter {
+
+    @Autowired
+    private UserDetailsService userDetailsService;
+
+    @Override
+    protected void configure(HttpSecurity http) throws Exception {
+        
+        http
+            .addFilterBefore(authenticationFilter(), UsernamePasswordAuthenticationFilter.class)
+            .authorizeRequests()
+                .antMatchers("/css/**", "/index").permitAll()
+                .antMatchers("/user/**").authenticated()
+            .and()
+            .formLogin().loginPage("/login")
+            .and()
+            .logout()
+            .logoutUrl("/logout");
+    }
+
+    public SimpleAuthenticationFilter authenticationFilter() throws Exception {
+        SimpleAuthenticationFilter filter = new SimpleAuthenticationFilter();
+        filter.setAuthenticationManager(authenticationManagerBean());
+        filter.setAuthenticationFailureHandler(failureHandler());
+        return filter;
+    }
+
+    @Autowired
+    public void configureGlobal(AuthenticationManagerBuilder auth) throws Exception {
+        auth.authenticationProvider(authProvider());
+    }
+
+    public AuthenticationProvider authProvider() {
+        DaoAuthenticationProvider provider = new DaoAuthenticationProvider();
+        provider.setUserDetailsService(userDetailsService);
+        provider.setPasswordEncoder(passwordEncoder());
+        return provider;
+    }
+
+    public SimpleUrlAuthenticationFailureHandler failureHandler() {
+        return new SimpleUrlAuthenticationFailureHandler("/login?error=true");
+    }
+
+    public PasswordEncoder passwordEncoder() {
+        return new BCryptPasswordEncoder();
+    }
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldssimple/SimpleAuthenticationFilter.java

@@ -0,0 +1,54 @@
+package com.baeldung.loginextrafieldssimple;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.springframework.security.authentication.AuthenticationServiceException;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.AuthenticationException;
+import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
+
+public class SimpleAuthenticationFilter extends UsernamePasswordAuthenticationFilter {
+
+    public static final String SPRING_SECURITY_FORM_DOMAIN_KEY = "domain";
+
+    @Override
+    public Authentication attemptAuthentication(HttpServletRequest request, HttpServletResponse response) 
+        throws AuthenticationException {
+
+        if (!request.getMethod()
+            .equals("POST")) {
+            throw new AuthenticationServiceException("Authentication method not supported: " + request.getMethod());
+        }
+
+        UsernamePasswordAuthenticationToken authRequest = getAuthRequest(request);
+        setDetails(request, authRequest);
+        return this.getAuthenticationManager()
+            .authenticate(authRequest);
+    }
+
+    private UsernamePasswordAuthenticationToken getAuthRequest(HttpServletRequest request) {
+        String username = obtainUsername(request);
+        String password = obtainPassword(request);
+        String domain = obtainDomain(request);
+
+        if (username == null) {
+            username = "";
+        }
+        if (password == null) {
+            password = "";
+        }
+        if (domain == null) {
+            domain = "";
+        }
+
+        String usernameDomain = String.format("%s%s%s", username.trim(), 
+            String.valueOf(Character.LINE_SEPARATOR), domain);
+        return new UsernamePasswordAuthenticationToken(usernameDomain, password);        
+    }
+
+    private String obtainDomain(HttpServletRequest request) {
+        return request.getParameter(SPRING_SECURITY_FORM_DOMAIN_KEY);
+    }
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldssimple/SimpleUserDetailsService.java

@@ -0,0 +1,32 @@
+package com.baeldung.loginextrafieldssimple;
+
+import org.apache.commons.lang3.StringUtils;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.core.userdetails.UserDetailsService;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
+import org.springframework.stereotype.Service;
+
+@Service("userDetailsService")
+public class SimpleUserDetailsService implements UserDetailsService {
+
+    private UserRepository userRepository;
+ 
+    public SimpleUserDetailsService(UserRepository userRepository) {
+        this.userRepository = userRepository;
+    }
+
+    @Override
+    public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
+        String[] usernameAndDomain = StringUtils.split(username, String.valueOf(Character.LINE_SEPARATOR));
+        if (usernameAndDomain == null || usernameAndDomain.length != 2) {
+            throw new UsernameNotFoundException("Username and domain must be provided");
+        }
+        User user = userRepository.findUser(usernameAndDomain[0], usernameAndDomain[1]);
+        if (user == null) {
+            throw new UsernameNotFoundException(
+                String.format("Username not found for domain, username=%s, domain=%s", 
+                    usernameAndDomain[0], usernameAndDomain[1]));
+        }
+        return user;
+    }
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldssimple/SimpleUserRepository.java

@@ -0,0 +1,26 @@
+package com.baeldung.loginextrafieldssimple;
+
+import java.util.ArrayList;
+import java.util.Collection;
+
+import org.apache.commons.lang3.StringUtils;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.stereotype.Repository;
+
+@Repository("userRepository")
+public class SimpleUserRepository implements UserRepository {
+
+    @Override
+    public User findUser(String username, String domain) {
+        if (StringUtils.isAnyBlank(username, domain)) {
+            return null;
+        } else {
+            Collection<? extends GrantedAuthority> authorities = new ArrayList<>();
+            User user =  new User(username, domain, 
+                "$2a$10$U3GhSMpsMSOE8Kqsbn58/edxDBKlVuYMh7qk/7ErApYFjJzi2VG5K", true, 
+                true, true, true, authorities);
+            return user;
+        }
+    }
+
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldssimple/User.java

@@ -0,0 +1,21 @@
+package com.baeldung.loginextrafieldssimple;
+
+import java.util.Collection;
+
+import org.springframework.security.core.GrantedAuthority;
+
+public class User extends org.springframework.security.core.userdetails.User {
+
+    private String domain;
+
+    public User(String username, String domain, String password, boolean enabled, 
+        boolean accountNonExpired, boolean credentialsNonExpired, 
+        boolean accountNonLocked, Collection<? extends GrantedAuthority> authorities) {
+        super(username, password, enabled, accountNonExpired, credentialsNonExpired, accountNonLocked, authorities);
+        this.domain = domain;
+    }
+
+    public String getDomain() {
+        return domain;
+    }
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldssimple/UserRepository.java

@@ -0,0 +1,7 @@
+package com.baeldung.loginextrafieldssimple;
+
+public interface UserRepository {
+
+    public User findUser(String username, String domain);
+    
+}

spring-5-security/src/main/java/com/baeldung/loginextrafieldssimple/WebController.java

@@ -0,0 +1,51 @@
+package com.baeldung.loginextrafieldssimple;
+
+import java.util.Optional;
+
+import org.springframework.security.authentication.AnonymousAuthenticationToken;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.RequestMapping;
+
+@Controller
+public class WebController {
+
+    @RequestMapping("/")
+    public String root() {
+        return "redirect:/index";
+    }
+
+    @RequestMapping("/index")
+    public String index(Model model) {
+        getDomain().ifPresent(d -> {
+            model.addAttribute("domain", d);
+        });
+        return "index";
+    }
+
+    @RequestMapping("/user/index")
+    public String userIndex(Model model) {
+        getDomain().ifPresent(d -> {
+            model.addAttribute("domain", d);
+        });
+        return "user/index";
+    }
+
+    @RequestMapping("/login")
+    public String login() {
+        return "login";
+    }
+
+    private Optional<String> getDomain() {
+        Authentication auth = SecurityContextHolder.getContext()
+            .getAuthentication(); 
+        String domain = null;
+        if (auth != null && !auth.getClass().equals(AnonymousAuthenticationToken.class)) {
+            User user = (User) auth.getPrincipal();
+            domain = user.getDomain();
+        }
+        return Optional.ofNullable(domain);
+    }
+}

spring-5-security/src/main/resources/application-extrafields.properties

@@ -0,0 +1 @@
+spring.thymeleaf.prefix = classpath:/templatesextrafields/

spring-5-security/src/main/resources/static/css/main.css

@@ -0,0 +1,8 @@
+p.error {
+    font-weight: bold;
+    color: red;
+}
+
+div.logout {
+    margin-right: 2em;;
+}

spring-5-security/src/main/resources/templatesextrafields/index.html

@@ -0,0 +1,32 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org" xmlns:sec="http://www.thymeleaf.org/thymeleaf-extras-springsecurity4" lang="en">
+    <head>
+        <title>Spring Security with Extra Fields</title>
+        <meta charset="utf-8" />
+        <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
+        <meta name="description" content="">
+        <meta name="author" content="">
+        <link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" crossorigin="anonymous">
+        <link href="http://getbootstrap.com/docs/4.0/examples/signin/signin.css" rel="stylesheet" crossorigin="anonymous"/>
+        <link rel="stylesheet" href="/css/main.css" th:href="@{/css/main.css}" />
+    </head>
+    <body>
+        <div class="container">
+        <div class="logout float-right" th:fragment="logout" sec:authorize="isAuthenticated()">
+            <p>Logged in: <span sec:authentication="name"></span> | <span th:text="${domain}">Some Domain</span>
+            </p>
+            <div>
+                <form action="#" th:action="@{/logout}" method="post">
+                    <button class="btn btn-sm btn-primary btn-block" type="submit">Logout</button>
+                </form>
+            </div>
+        </div>
+
+        <h2>Hello Spring Security</h2>
+        <p>This is an unsecured page, but you can access the secured pages after authenticating.</p>
+        <ul>
+            <li>Go to the <a href="/user/index" th:href="@{/user/index}">secured pages</a></li>
+        </ul>
+        </div>
+    </body>
+</html>

spring-5-security/src/main/resources/templatesextrafields/login.html

@@ -0,0 +1,36 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org" lang="en">
+  <head>
+      <title>Login page</title>
+      <meta charset="utf-8" />
+      <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
+      <meta name="description" content="">
+      <meta name="author" content="">
+      <link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" crossorigin="anonymous">
+      <link href="http://getbootstrap.com/docs/4.0/examples/signin/signin.css" rel="stylesheet" crossorigin="anonymous"/>
+      <link rel="stylesheet" href="/css/main.css" th:href="@{/css/main.css}" />
+  </head>
+  <body>
+    <div class="container">
+      <form class="form-signin" th:action="@{/login}" method="post">
+        <h2 class="form-signin-heading">Please sign in</h2>
+        <p>Example: user / domain / password</p>
+        <p th:if="${param.error}" class="error">Invalid user, password, or domain</p>
+        <p>
+          <label for="username" class="sr-only">Username</label>
+          <input type="text" id="username" name="username" class="form-control" placeholder="Username" required autofocus/>
+        </p>
+        <p>
+          <label for="domain" class="sr-only">Domain</label>
+          <input type="text" id="domain" name="domain" class="form-control" placeholder="Domain" required autofocus/>
+        </p>
+        <p>
+          <label for="password" class="sr-only">Password</label>
+          <input type="password" id="password" name="password" class="form-control" placeholder="Password" required autofocus/>
+        </p>
+        <button class="btn btn-lg btn-primary btn-block" type="submit">Sign in</button><br/>
+        <p><a href="/index" th:href="@{/index}">Back to home page</a></p>
+      </form>
+    </div>
+  </body>
+</html>

spring-5-security/src/main/resources/templatesextrafields/user/index.html

@@ -0,0 +1,20 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xmlns:th="http://www.thymeleaf.org" lang="en">
+<head>
+  <title>Secured Page</title>
+  <meta charset="utf-8" />
+  <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
+  <meta name="description" content="">
+  <meta name="author" content="">
+  <link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-/Y6pD6FV/Vv2HJnA6t+vslU6fwYXjCFtcEpHbNJ0lyAFsXTsjBbfaDjzALeQsN6M" crossorigin="anonymous">
+  <link href="http://getbootstrap.com/docs/4.0/examples/signin/signin.css" rel="stylesheet" crossorigin="anonymous"/>
+  <link rel="stylesheet" href="/css/main.css" th:href="@{/css/main.css}" />
+</head>
+<body>
+    <div class="container">
+      <div th:replace="index::logout"></div>
+      <h2>This is a secured page!</h2>
+      <p><a href="/index" th:href="@{/index}">Back to home page</a></p>
+    </div>
+</body>
+</html>

spring-5-security/src/test/java/com/baeldung/loginextrafields/AbstractExtraLoginFieldsTest.java

@@ -0,0 +1,46 @@
+package com.baeldung.loginextrafields;
+
+import static org.springframework.security.test.web.servlet.setup.SecurityMockMvcConfigurers.springSecurity;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.redirectedUrlPattern;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.security.web.FilterChainProxy;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+import org.springframework.web.context.WebApplicationContext;
+
+public abstract class AbstractExtraLoginFieldsTest {
+
+    @Autowired
+    private FilterChainProxy springSecurityFilterChain;
+
+    @Autowired
+    private WebApplicationContext wac;
+
+    protected MockMvc mockMvc;
+
+    @Before
+    public void setup() {
+        this.mockMvc = MockMvcBuilders.webAppContextSetup(wac)
+            .apply(springSecurity(springSecurityFilterChain))
+            .build();
+    }
+
+    @Test
+    public void givenRootPathAccess_thenRedirectToIndex() throws Exception {
+        this.mockMvc.perform(get("/"))
+            .andExpect(status().is3xxRedirection())
+            .andExpect(redirectedUrlPattern("/index*"));
+    }
+
+    @Test
+    public void givenSecuredResource_whenAccessUnauthenticated_thenRequiresAuthentication() throws Exception {
+        this.mockMvc.perform(get("/user/index"))
+            .andExpect(status().is3xxRedirection())
+            .andExpect(redirectedUrlPattern("**/login"));
+    }
+}

spring-5-security/src/test/java/com/baeldung/loginextrafields/LoginFieldsFullTest.java

@@ -0,0 +1,72 @@
+package com.baeldung.loginextrafields;
+
+import static org.junit.Assert.assertEquals;
+import static org.springframework.security.test.web.servlet.request.SecurityMockMvcRequestPostProcessors.csrf;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.redirectedUrlPattern;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import java.util.ArrayList;
+import java.util.Collection;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.mock.web.MockHttpSession;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.context.SecurityContext;
+import org.springframework.security.web.context.HttpSessionSecurityContextRepository;
+import org.springframework.test.context.junit.jupiter.web.SpringJUnitWebConfig;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.web.servlet.MvcResult;
+import org.springframework.test.web.servlet.request.MockHttpServletRequestBuilder;
+
+import com.baeldung.loginextrafieldscustom.ExtraLoginFieldsApplication;
+import com.baeldung.loginextrafieldscustom.User;
+
+@RunWith(SpringRunner.class)
+@SpringJUnitWebConfig
+@SpringBootTest(classes = ExtraLoginFieldsApplication.class)
+public class LoginFieldsFullTest extends AbstractExtraLoginFieldsTest {
+
+    @Test
+    public void givenAccessSecuredResource_whenAuthenticated_thenAuthHasExtraFields() throws Exception {
+        MockHttpServletRequestBuilder securedResourceAccess = get("/user/index");
+        MvcResult unauthenticatedResult = mockMvc.perform(securedResourceAccess)
+            .andExpect(status().is3xxRedirection())
+            .andReturn();
+
+        MockHttpSession session = (MockHttpSession) unauthenticatedResult.getRequest()
+            .getSession();
+        String loginUrl = unauthenticatedResult.getResponse()
+            .getRedirectedUrl();
+
+        User user = getUser();
+
+        mockMvc.perform(post(loginUrl)
+            .param("username", user.getUsername())
+            .param("password", user.getPassword())
+            .param("domain", user.getDomain())
+            .session(session)
+            .with(csrf()))
+            .andExpect(status().is3xxRedirection())
+            .andExpect(redirectedUrlPattern("**/user/index"))
+            .andReturn();
+
+        mockMvc.perform(securedResourceAccess.session(session))
+            .andExpect(status().isOk());
+        
+        SecurityContext securityContext 
+            = (SecurityContext) session.getAttribute(HttpSessionSecurityContextRepository.SPRING_SECURITY_CONTEXT_KEY);
+        Authentication auth = securityContext.getAuthentication();
+        assertEquals(((User)auth.getPrincipal()).getDomain(), user.getDomain());
+    }
+
+    private User getUser() {
+        Collection<? extends GrantedAuthority> authorities = new ArrayList<>();
+        return new User("myusername", "mydomain", "password", true, true, true, true, authorities);
+    }
+
+}

spring-5-security/src/test/java/com/baeldung/loginextrafields/LoginFieldsSimpleTest.java

@@ -0,0 +1,72 @@
+package com.baeldung.loginextrafields;
+
+import static org.junit.Assert.assertEquals;
+import static org.springframework.security.test.web.servlet.request.SecurityMockMvcRequestPostProcessors.csrf;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.redirectedUrlPattern;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import java.util.ArrayList;
+import java.util.Collection;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.mock.web.MockHttpSession;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.GrantedAuthority;
+import org.springframework.security.core.context.SecurityContext;
+import org.springframework.security.web.context.HttpSessionSecurityContextRepository;
+import org.springframework.test.context.junit.jupiter.web.SpringJUnitWebConfig;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.web.servlet.MvcResult;
+import org.springframework.test.web.servlet.request.MockHttpServletRequestBuilder;
+
+import com.baeldung.loginextrafieldssimple.ExtraLoginFieldsApplication;
+import com.baeldung.loginextrafieldssimple.User;
+
+@RunWith(SpringRunner.class)
+@SpringJUnitWebConfig
+@SpringBootTest(classes = ExtraLoginFieldsApplication.class)
+public class LoginFieldsSimpleTest extends AbstractExtraLoginFieldsTest {
+
+    @Test
+    public void givenAccessSecuredResource_whenAuthenticated_thenAuthHasExtraFields() throws Exception {
+        MockHttpServletRequestBuilder securedResourceAccess = get("/user/index");
+        MvcResult unauthenticatedResult = mockMvc.perform(securedResourceAccess)
+            .andExpect(status().is3xxRedirection())
+            .andReturn();
+
+        MockHttpSession session = (MockHttpSession) unauthenticatedResult.getRequest()
+            .getSession();
+        String loginUrl = unauthenticatedResult.getResponse()
+            .getRedirectedUrl();
+
+        User user = getUser();
+
+        mockMvc.perform(post(loginUrl)
+            .param("username", user.getUsername())
+            .param("password", user.getPassword())
+            .param("domain", user.getDomain())
+            .session(session)
+            .with(csrf()))
+            .andExpect(status().is3xxRedirection())
+            .andExpect(redirectedUrlPattern("**/user/index"))
+            .andReturn();
+
+        mockMvc.perform(securedResourceAccess.session(session))
+            .andExpect(status().isOk());
+        
+        SecurityContext securityContext 
+            = (SecurityContext) session.getAttribute(HttpSessionSecurityContextRepository.SPRING_SECURITY_CONTEXT_KEY);
+        Authentication auth = securityContext.getAuthentication();
+        assertEquals(((User)auth.getPrincipal()).getDomain(), user.getDomain());
+    }
+
+    private User getUser() {
+        Collection<? extends GrantedAuthority> authorities = new ArrayList<>();
+        return new User("myusername", "mydomain", "password", true, true, true, true, authorities);
+    }
+
+}

spring-boot-security/README.md

@@ -1,6 +1,8 @@
 ### Spring Boot Security Auto-Configuration
 
 - mvn clean install 
-- uncomment in application.properties spring.profiles.active=basic # for basic auth config
-- uncomment in application.properties spring.profiles.active=form # for form based auth config
-- uncomment actuator dependency simultaneously with the line from main class
+- uncomment actuator dependency simultaneously with the line from basic auth main class
+- uncomment security properties for easy testing. If not random will be generated.
+
+### CURL commands
+- curl -X POST -u baeldung-admin:baeldung -d grant_type=client_credentials -d username=baeldung-admin -d password=baeldung http://localhost:8080/oauth/token

spring-boot-security/pom.xml

@@ -43,6 +43,10 @@
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-security</artifactId>
 		</dependency>
+		<dependency>
+			<groupId>org.springframework.security.oauth</groupId>
+			<artifactId>spring-security-oauth2</artifactId>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-web</artifactId>