Merge branch 'master' into thombergs-patch-31-1

README.md

@@ -2,41 +2,22 @@
 The "REST with Spring" Classes
 ==============================
 
-Here's the Master Class of REST With Spring (price changes permanently next Friday): <br/>
-**[>> THE REST WITH SPRING MASTER CLASS](http://www.baeldung.com/rest-with-spring-course?utm_source=github&utm_medium=social&utm_content=tutorials&utm_campaign=rws#master-class)**
+Here's the Master Class of REST With Spring (along with the newly announced Boot 2 material): <br/>
+**[>> THE REST WITH SPRING - MASTER CLASS](http://www.baeldung.com/rest-with-spring-course?utm_source=github&utm_medium=social&utm_content=tutorials&utm_campaign=rws#master-class)**
 
 And here's the Master Class of Learn Spring Security: <br/>
-**[>> LEARN SPRING SECURITY MASTER CLASS](http://www.baeldung.com/learn-spring-security-course?utm_source=github&utm_medium=social&utm_content=tutorials&utm_campaign=lss#master-class)**
+**[>> LEARN SPRING SECURITY - MASTER CLASS](http://www.baeldung.com/learn-spring-security-course?utm_source=github&utm_medium=social&utm_content=tutorials&utm_campaign=lss#master-class)**
 
 
 
-Spring Tutorials
+Java and Spring Tutorials
 ================
 
-This project is **a collection of small and focused tutorials** each covering a single and well defined area of development. 
-Most of the tutorial projects are focused on the `Spring Framework` (and `Spring Security`).  
+This project is **a collection of small and focused tutorials** - each covering a single and well defined area of development in the Java ecosystem. 
+A strong focus of these is, of course, the Spring Framework - Spring, Spring Boot and Spring Securiyt. 
 In additional to Spring, the following technologies are in focus: `core Java`, `Jackson`, `HttpClient`, `Guava`. 
 
+
 Building the project
 ====================
 To do the full build, do: `mvn install -Pdefault -Dgib.enabled=false`
-
-
-Working with the code in Eclipse
-================================
-Any IDE can be used to work with the projects, but if you're using Eclipse, consider the following. 
-
-- import the included **formatter** in Eclipse: 
-`https://github.com/eugenp/tutorials/tree/master/eclipse`
-
-
-CI - Jenkins
-================================
-This tutorials project is being built **[>> HERE](https://rest-security.ci.cloudbees.com/job/tutorials-unit/)**
-
-### Relevant Articles: 
-================================
-
-- [Apache Maven Standard Directory Layout](http://www.baeldung.com/maven-directory-structure)
-- [Apache Maven Tutorial](http://www.baeldung.com/maven)
-- [Designing a User Friendly Java Library](http://www.baeldung.com/design-a-user-friendly-java-library)

algorithms/src/main/java/com/baeldung/algorithms/kthlargest/FindKthLargest.java

@@ -98,7 +98,7 @@ public class FindKthLargest {
 
     private int randomPartition(Integer arr[], int left, int right) {
         int n = right - left + 1;
-        int pivot = (int) (Math.random()) % n;
+        int pivot = (int) (Math.random() * n);
         swap(arr, left + pivot, right);
         return partition(arr, left, right);
     }

core-java-8/src/test/java/com/baeldung/java8/Java8SortUnitTest.java

@@ -1,16 +1,18 @@
 package com.baeldung.java8;
 
-import com.baeldung.java8.entity.Human;
-import com.google.common.collect.Lists;
-import com.google.common.primitives.Ints;
-import org.junit.Assert;
-import org.junit.Test;
+import static org.hamcrest.Matchers.equalTo;
 
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
+import java.util.stream.Collectors;
 
-import static org.hamcrest.Matchers.equalTo;
+import org.junit.Assert;
+import org.junit.Test;
+
+import com.baeldung.java8.entity.Human;
+import com.google.common.collect.Lists;
+import com.google.common.primitives.Ints;
 
 public class Java8SortUnitTest {
 
@@ -111,5 +113,22 @@ public class Java8SortUnitTest {
         humans.sort(Comparator.comparing(Human::getName));
         Assert.assertThat(humans.get(0), equalTo(new Human("Jack", 12)));
     }
+    
+    @Test
+    public final void givenStreamNaturalOrdering_whenSortingEntitiesByName_thenCorrectlySorted() {
+        final List<String> letters = Lists.newArrayList("B", "A", "C");
+        
+        final List<String> sortedLetters = letters.stream().sorted().collect(Collectors.toList());
+        Assert.assertThat(sortedLetters.get(0), equalTo("A"));
+    }
 
+    @Test
+    public final void givenStreamCustomOrdering_whenSortingEntitiesByName_thenCorrectlySorted() {
+        
+        final List<Human> humans = Lists.newArrayList(new Human("Sarah", 10), new Human("Jack", 12));
+        final Comparator<Human> nameComparator = (h1, h2) -> h1.getName().compareTo(h2.getName());
+        
+        final List<Human> sortedHumans = humans.stream().sorted(nameComparator).collect(Collectors.toList());
+        Assert.assertThat(sortedHumans.get(0), equalTo(new Human("Jack", 12)));
+    }
 }

core-java-collections/README.md

@@ -48,6 +48,7 @@
 - [Thread Safe LIFO Data Structure Implementations](https://www.baeldung.com/java-lifo-thread-safe)
 - [Collections.emptyList() vs. New List Instance](https://www.baeldung.com/java-collections-emptylist-new-list)
 - [Initialize a HashMap in Java](https://www.baeldung.com/java-initialize-hashmap)
+- [Differences Between Collection.clear() and Collection.removeAll()](https://www.baeldung.com/java-collection-clear-vs-removeall)
 - [Performance of contains() in a HashSet vs ArrayList](https://www.baeldung.com/java-hashset-arraylist-contains-performance)
 - [Get the Key for a Value from a Java Map](https://www.baeldung.com/java-map-key-from-value)
 - [Time Complexity of Java Collections](https://www.baeldung.com/java-collections-complexity)

core-java-collections/pom.xml

@@ -68,6 +68,11 @@
 		    <artifactId>commons-exec</artifactId>
 		    <version>1.3</version>
 		</dependency>
+        <dependency>
+            <groupId>one.util</groupId>
+            <artifactId>streamex</artifactId>
+            <version>0.6.5</version>
+        </dependency>
 		        
     </dependencies>
 

core-java-collections/src/main/java/com/baeldung/map/java_8/MergeMaps.java

@@ -0,0 +1,105 @@
+package com.baeldung.map.java_8;
+
+import com.baeldung.sort.Employee;
+import one.util.streamex.EntryStream;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+public class MergeMaps {
+
+    private static Map<String, Employee> map1 = new HashMap<>();
+    private static Map<String, Employee> map2 = new HashMap<>();
+
+    public static void main(String[] args) {
+
+        initialize();
+
+        mergeFunction();
+
+        streamConcat();
+
+        streamOf();
+
+        streamEx();
+
+        streamMerge();
+    }
+
+    private static void streamMerge() {
+
+        Map<String, Employee> map3 = map2.entrySet()
+                .stream()
+                .collect(
+                        Collectors.toMap(
+                                Map.Entry::getKey,
+                                Map.Entry::getValue,
+                                (v1, v2) -> new Employee(v1.getId(), v2.getName()),
+                                () -> new HashMap<>(map1)
+                        )
+                );
+
+        System.out.println(map3);
+    }
+
+    private static void streamEx() {
+        Map<String, Employee> map3 = EntryStream.of(map1)
+                .append(EntryStream.of(map2))
+                .toMap((e1, e2) -> e1);
+
+        System.out.println(map3);
+
+    }
+
+    private static void streamOf() {
+        Map<String, Employee> map3 = Stream.of(map1, map2)
+                .flatMap(map -> map.entrySet().stream())
+                .collect(
+                        Collectors.toMap(
+                                Map.Entry::getKey,
+                                Map.Entry::getValue,
+                                (v1, v2) -> new Employee(v1.getId(), v2.getName())
+                        )
+                );
+
+        map3.entrySet().forEach(System.out::println);
+    }
+
+    private static void streamConcat() {
+        Map<String, Employee> result = Stream.concat(map1.entrySet().stream(), map2.entrySet().stream()).collect(Collectors.toMap(
+                Map.Entry::getKey,
+                Map.Entry::getValue,
+                (value1, value2) -> new Employee(value2.getId(), value1.getName())
+        ));
+
+        result.entrySet().forEach(System.out::println);
+    }
+
+    private static void mergeFunction() {
+        Map<String, Employee> map3 = new HashMap<>(map1);
+
+        map2.forEach(
+                (key, value) -> map3.merge(key, value, (v1, v2) ->
+                        new Employee(v1.getId(), v2.getName()))
+        );
+
+        map3.entrySet().forEach(System.out::println);
+    }
+
+
+    private static void initialize() {
+        Employee employee1 = new Employee(1L, "Henry");
+        map1.put(employee1.getName(), employee1);
+        Employee employee2 = new Employee(22L, "Annie");
+        map1.put(employee2.getName(), employee2);
+        Employee employee3 = new Employee(8L, "John");
+        map1.put(employee3.getName(), employee3);
+
+        Employee employee4 = new Employee(2L, "George");
+        map2.put(employee4.getName(), employee4);
+        Employee employee5 = new Employee(3L, "Henry");
+        map2.put(employee5.getName(), employee5);
+    }
+
+}

core-java-collections/src/test/java/com/baeldung/java/map/KeyCheckTest.java

@@ -0,0 +1,44 @@
+package com.baeldung.java.map;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.apache.commons.collections4.MultiMap;
+import org.apache.commons.collections4.MultiMapUtils;
+import org.apache.commons.collections4.MultiValuedMap;
+import org.apache.commons.collections4.map.MultiValueMap;
+import org.apache.commons.collections4.multimap.ArrayListValuedHashMap;
+import org.apache.commons.collections4.multimap.HashSetValuedHashMap;
+import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.google.common.collect.ArrayListMultimap;
+import com.google.common.collect.LinkedHashMultimap;
+import com.google.common.collect.Multimap;
+import com.google.common.collect.TreeMultimap;
+
+
+public class KeyCheckTest {
+
+    @Test
+    public void whenKeyIsPresent_thenContainsKeyReturnsTrue() {
+        Map<String, String> map = Collections.singletonMap("key", "value");
+
+        assertTrue(map.containsKey("key"));
+        assertFalse(map.containsKey("missing"));
+    }
+
+    @Test
+    public void whenKeyHasNullValue_thenGetStillWorks() {
+        Map<String, String> map = Collections.singletonMap("nothing", null);
+
+        assertTrue(map.containsKey("nothing"));
+        assertNull(map.get("nothing"));
+    }
+}

core-java-io/src/main/java/com/baeldung/stream/OutputStreamExamples.java

@@ -0,0 +1,48 @@
+package com.baeldung.stream;
+
+import java.io.BufferedOutputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.io.Writer;
+
+public class OutputStreamExamples {
+
+    public void fileOutputStreamByteSequence(String file, String data) throws IOException {
+        byte[] bytes = data.getBytes();
+        try (OutputStream out = new FileOutputStream(file)) {
+            out.write(bytes);
+        }
+    }
+
+    public void fileOutputStreamByteSubSequence(String file, String data) throws IOException {
+        byte[] bytes = data.getBytes();
+        try (OutputStream out = new FileOutputStream(file)) {
+            out.write(bytes, 6, 5);
+        }
+    }
+
+    public void fileOutputStreamByteSingle(String file, String data) throws IOException {
+        byte[] bytes = data.getBytes();
+        try (OutputStream out = new FileOutputStream(file)) {
+            out.write(bytes[6]);
+        }
+    }
+
+    public void bufferedOutputStream(String file, String... data) throws IOException {
+        try (BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(file))) {
+            for (String s : data) {
+                out.write(s.getBytes());
+                out.write(" ".getBytes());
+            }
+        }
+    }
+
+    public void outputStreamWriter(String file, String data) throws IOException {
+        try (OutputStream out = new FileOutputStream(file); Writer writer = new OutputStreamWriter(out, "UTF-8")) {
+            writer.write(data);
+        }
+    }
+
+}

core-java-io/src/test/java/com/baeldung/stream/OutputStreamExamplesTest.java

@@ -0,0 +1,76 @@
+package com.baeldung.stream;
+
+import static org.junit.Assert.assertTrue;
+
+import java.io.File;
+import java.io.IOException;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class OutputStreamExamplesTest {
+    
+    StringBuilder filePath = new StringBuilder();
+    
+    @Before
+    public void init() {
+        filePath.append("src");
+        filePath.append(File.separator);
+        filePath.append("test");
+        filePath.append(File.separator);
+        filePath.append("resources");
+        filePath.append(File.separator);
+        filePath.append("output_file.txt");
+    }
+    
+    @Test
+    public void givenOutputStream_whenWriteSingleByteCalled_thenOutputCreated() throws IOException {
+        
+        final File file = new File(filePath.toString());    
+        OutputStreamExamples examples = new OutputStreamExamples();    
+        examples.fileOutputStreamByteSingle(filePath.toString(), "Hello World!");
+        assertTrue(file.exists());
+        file.delete();
+    }
+    
+    @Test
+    public void givenOutputStream_whenWriteByteSequenceCalled_thenOutputCreated() throws IOException {
+        
+        final File file = new File(filePath.toString());    
+        OutputStreamExamples examples = new OutputStreamExamples();    
+        examples.fileOutputStreamByteSequence(filePath.toString(), "Hello World!");
+        assertTrue(file.exists());
+        file.delete();
+    }
+    
+    @Test
+    public void givenOutputStream_whenWriteByteSubSequenceCalled_thenOutputCreated() throws IOException {
+        
+        final File file = new File(filePath.toString());    
+        OutputStreamExamples examples = new OutputStreamExamples();    
+        examples.fileOutputStreamByteSubSequence(filePath.toString(), "Hello World!");
+        assertTrue(file.exists());
+        file.delete();
+    }
+
+    @Test
+    public void givenBufferedOutputStream_whenCalled_thenOutputCreated() throws IOException {
+        
+        final File file = new File(filePath.toString());    
+        OutputStreamExamples examples = new OutputStreamExamples();    
+        examples.bufferedOutputStream(filePath.toString(), "Hello", "World!");
+        assertTrue(file.exists());
+        file.delete();
+    }
+    
+    @Test
+    public void givenOutputStreamWriter_whenCalled_thenOutputCreated() throws IOException {
+        
+        final File file = new File(filePath.toString());    
+        OutputStreamExamples examples = new OutputStreamExamples();    
+        examples.outputStreamWriter(filePath.toString(), "Hello World!");
+        assertTrue(file.exists());
+        file.delete();
+    }
+
+}

core-java/README.md

@@ -25,7 +25,6 @@
 - [The Traveling Salesman Problem in Java](http://www.baeldung.com/java-simulated-annealing-for-traveling-salesman)
 - [How to Create an Executable JAR with Maven](http://www.baeldung.com/executable-jar-with-maven)
 - [How to Design a Genetic Algorithm in Java](http://www.baeldung.com/java-genetic-algorithm)
-- [Spring Security – Cache Control Headers](http://www.baeldung.com/spring-security-cache-control-headers)
 - [Basic Introduction to JMX](http://www.baeldung.com/java-management-extensions)
 - [AWS Lambda With Java](http://www.baeldung.com/java-aws-lambda)
 - [Introduction to Nashorn](http://www.baeldung.com/java-nashorn)
@@ -37,7 +36,6 @@
 - [Guide to sun.misc.Unsafe](http://www.baeldung.com/java-unsafe)
 - [How to Perform a Simple HTTP Request in Java](http://www.baeldung.com/java-http-request)
 - [Call Methods at Runtime Using Java Reflection](http://www.baeldung.com/java-method-reflection)
-- [Guide to UUID in JAVA](http://www.baeldung.com/guide-to-uuid-in-java)
 - [How to Add a Single Element to a Stream](http://www.baeldung.com/java-stream-append-prepend)
 - [Iterating Over Enum Values in Java](http://www.baeldung.com/java-enum-iteration)
 - [Kotlin Java Interoperability](http://www.baeldung.com/kotlin-java-interoperability)

core-kotlin/src/test/kotlin/com/baeldung/kotlin/StructuralJumpUnitTest.kt

@@ -0,0 +1,121 @@
+package com.baeldung.kotlin
+
+import org.junit.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+
+class StructuralJumpUnitTest {
+
+    @Test
+    fun givenLoop_whenBreak_thenComplete() {
+        var value = ""
+        for (i in "hello_world") {
+            if (i == '_')
+                break
+            value += i.toString()
+        }
+        assertEquals("hello", value)
+    }
+    @Test
+    fun givenLoop_whenBreakWithLabel_thenComplete() {
+        var value = ""
+        outer_loop@ for (i in 'a'..'d') {
+            for (j in 1..3) {
+                value += "" + i + j
+                if (i == 'b' && j == 1)
+                    break@outer_loop
+            }
+        }
+        assertEquals("a1a2a3b1", value)
+    }
+
+    @Test
+    fun givenLoop_whenContinue_thenComplete() {
+        var result = ""
+        for (i in "hello_world") {
+            if (i == '_')
+                continue
+            result += i
+        }
+        assertEquals("helloworld", result)
+    }
+    @Test
+    fun givenLoop_whenContinueWithLabel_thenComplete() {
+        var result = ""
+        outer_loop@ for (i in 'a'..'c') {
+            for (j in 1..3) {
+                if (i == 'b')
+                    continue@outer_loop
+                result += "" + i + j
+            }
+        }
+        assertEquals("a1a2a3c1c2c3", result)
+    }
+
+    @Test
+    fun givenLambda_whenReturn_thenComplete() {
+        var result = returnInLambda();
+        assertEquals("hello", result)
+    }
+
+    private fun returnInLambda(): String {
+        var result = ""
+        "hello_world".forEach {
+            // non-local return directly to the caller
+            if (it == '_') return result
+            result += it.toString()
+        }
+        //this line won't be reached
+        return result;
+    }
+
+    @Test
+    fun givenLambda_whenReturnWithExplicitLabel_thenComplete() {
+        var result = ""
+        "hello_world".forEach lit@{
+            if (it == '_') {
+                // local return to the caller of the lambda, i.e. the forEach loop
+                return@lit
+            }
+            result += it.toString()
+        }
+        assertEquals("helloworld", result)
+    }
+
+    @Test
+    fun givenLambda_whenReturnWithImplicitLabel_thenComplete() {
+        var result = ""
+        "hello_world".forEach {
+            if (it == '_') {
+                // local return to the caller of the lambda, i.e. the forEach loop
+                return@forEach
+            }
+            result += it.toString()
+        }
+        assertEquals("helloworld", result)
+    }
+
+    @Test
+    fun givenAnonymousFunction_return_thenComplete() {
+        var result = ""
+        "hello_world".forEach(fun(element) {
+            // local return to the caller of the anonymous fun, i.e. the forEach loop
+            if (element == '_') return
+            result += element.toString()
+        })
+        assertEquals("helloworld", result)
+    }
+
+    @Test
+    fun givenAnonymousFunction_returnToLabel_thenComplete() {
+        var result = ""
+        run loop@{
+            "hello_world".forEach {
+                // non-local return from the lambda passed to run
+                if (it == '_') return@loop
+                result += it.toString()
+            }
+        }
+        assertEquals("hello", result)
+    }
+}

hibernate5/README.md

@@ -14,4 +14,5 @@
 - [Bootstrapping JPA Programmatically in Java](http://www.baeldung.com/java-bootstrap-jpa)
 - [Optimistic Locking in JPA](http://www.baeldung.com/jpa-optimistic-locking)
 - [Hibernate Entity Lifecycle](https://www.baeldung.com/hibernate-entity-lifecycle)
+- [Mapping A Hibernate Query to a Custom Class](https://www.baeldung.com/hibernate-query-to-custom-class)
 - [@JoinColumn Annotation Explained](https://www.baeldung.com/jpa-join-column)

hibernate5/src/main/java/com/baeldung/hibernate/namingstrategy/CustomPhysicalNamingStrategy.java

@@ -0,0 +1,47 @@
+package com.baeldung.hibernate.namingstrategy;
+
+import org.hibernate.boot.model.naming.Identifier;
+import org.hibernate.boot.model.naming.PhysicalNamingStrategy;
+import org.hibernate.engine.jdbc.env.spi.JdbcEnvironment;
+
+public class CustomPhysicalNamingStrategy implements PhysicalNamingStrategy {
+
+    @Override
+    public Identifier toPhysicalCatalogName(final Identifier identifier, final JdbcEnvironment jdbcEnv) {
+        return convertToSnakeCase(identifier);
+    }
+
+    @Override
+    public Identifier toPhysicalColumnName(final Identifier identifier, final JdbcEnvironment jdbcEnv) {
+        return convertToSnakeCase(identifier);
+    }
+
+    @Override
+    public Identifier toPhysicalSchemaName(final Identifier identifier, final JdbcEnvironment jdbcEnv) {
+        return convertToSnakeCase(identifier);
+    }
+
+    @Override
+    public Identifier toPhysicalSequenceName(final Identifier identifier, final JdbcEnvironment jdbcEnv) {
+        return convertToSnakeCase(identifier);
+    }
+
+    @Override
+    public Identifier toPhysicalTableName(final Identifier identifier, final JdbcEnvironment jdbcEnv) {
+        return convertToSnakeCase(identifier);
+    }
+
+    private Identifier convertToSnakeCase(final Identifier identifier) {
+        if (identifier == null) {
+            return identifier;
+        }
+
+        final String regex = "([a-z])([A-Z])";
+        final String replacement = "$1_$2";
+        final String newName = identifier.getText()
+            .replaceAll(regex, replacement)
+            .toLowerCase();
+        return Identifier.toIdentifier(newName);
+    }
+
+}

hibernate5/src/main/java/com/baeldung/hibernate/namingstrategy/Customer.java

@@ -0,0 +1,56 @@
+package com.baeldung.hibernate.namingstrategy;
+
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import javax.persistence.Table;
+
+@Entity
+@Table(name = "Customers")
+public class Customer {
+
+    @Id
+    @GeneratedValue
+    private Long id;
+
+    private String firstName;
+
+    private String lastName;
+
+    @Column(name = "email")
+    private String emailAddress;
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getFirstName() {
+        return firstName;
+    }
+
+    public void setFirstName(String firstName) {
+        this.firstName = firstName;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public void setLastName(String lastName) {
+        this.lastName = lastName;
+    }
+
+    public String getEmailAddress() {
+        return emailAddress;
+    }
+
+    public void setEmailAddress(String emailAddress) {
+        this.emailAddress = emailAddress;
+    }
+
+}

hibernate5/src/test/java/com/baeldung/hibernate/namingstrategy/NamingStrategyLiveTest.java

@@ -0,0 +1,75 @@
+package com.baeldung.hibernate.namingstrategy;
+
+import static org.junit.Assert.fail;
+
+import java.io.IOException;
+import java.util.Properties;
+
+import org.hibernate.HibernateException;
+import org.hibernate.Session;
+import org.hibernate.SessionFactory;
+import org.hibernate.boot.MetadataSources;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.hibernate.cfg.Configuration;
+import org.hibernate.service.ServiceRegistry;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+public class NamingStrategyLiveTest {
+
+    private Session session;
+
+    @Before
+    public void init() {
+        try {
+            Configuration configuration = new Configuration();
+
+            Properties properties = new Properties();
+            properties.load(Thread.currentThread()
+                .getContextClassLoader()
+                .getResourceAsStream("hibernate-namingstrategy.properties"));
+
+            configuration.setProperties(properties);
+
+            ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties())
+                .build();
+            MetadataSources metadataSources = new MetadataSources(serviceRegistry);
+            metadataSources.addAnnotatedClass(Customer.class);
+
+            SessionFactory factory = metadataSources.buildMetadata()
+                .buildSessionFactory();
+
+            session = factory.openSession();
+        } catch (HibernateException | IOException e) {
+            fail("Failed to initiate Hibernate Session [Exception:" + e.toString() + "]");
+        }
+    }
+
+    @After
+    public void close() {
+        if (session != null)
+            session.close();
+    }
+
+    @Test
+    public void testCustomPhysicalNamingStrategy() {
+
+        Customer customer = new Customer();
+        customer.setFirstName("first name");
+        customer.setLastName("last name");
+        customer.setEmailAddress("[email protected]");
+
+        session.beginTransaction();
+
+        Long id = (Long) session.save(customer);
+
+        session.flush();
+        session.clear();
+
+        Object[] result = (Object[]) session.createNativeQuery("select c.first_name, c.last_name, c.email from customers c where c.id = :id")
+            .setParameter("id", id)
+            .getSingleResult();
+
+    }
+}

hibernate5/src/test/resources/hibernate-namingstrategy.properties

@@ -0,0 +1,10 @@
+hibernate.connection.driver_class=org.h2.Driver
+hibernate.connection.url=jdbc:h2:mem:mydb1;DB_CLOSE_DELAY=-1
+hibernate.connection.username=sa
+hibernate.dialect=org.hibernate.dialect.H2Dialect
+
+hibernate.show_sql=true
+hibernate.hbm2ddl.auto=create-drop
+
+hibernate.physical_naming_strategy=com.baeldung.hibernate.namingstrategy.CustomPhysicalNamingStrategy
+hibernate.implicit_naming_strategy=org.hibernate.boot.model.naming.ImplicitNamingStrategyJpaCompliantImpl

jackson/pom.xml

@@ -118,7 +118,7 @@
 
     <properties>
         <!-- marshalling -->
-        <jackson.version>2.9.6</jackson.version>
+        <jackson.version>2.9.7</jackson.version>
         <!-- util -->
         <commons-lang3.version>3.8</commons-lang3.version>
         <joda-time.version>2.10</joda-time.version>

jackson/src/main/java/com/baeldung/jackson/xmlToJson/Color.java

@@ -0,0 +1,5 @@
+package com.baeldung.jackson.xmlToJson;
+
+public enum Color {
+    PINK, BLUE, YELLOW, RED;
+}

jackson/src/main/java/com/baeldung/jackson/xmlToJson/Flower.java

@@ -0,0 +1,42 @@
+package com.baeldung.jackson.xmlToJson;
+
+public class Flower {
+
+    private String name;
+
+    private Color color;
+
+    private Integer petals;
+
+    public Flower() { }
+
+    public Flower(String name, Color color, Integer petals) {
+        this.name = name;
+        this.color = color;
+        this.petals = petals;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public Color getColor() {
+        return color;
+    }
+
+    public void setColor(Color color) {
+        this.color = color;
+    }
+
+    public Integer getPetals() {
+        return petals;
+    }
+
+    public void setPetals(Integer petals) {
+        this.petals = petals;
+    }
+}

jackson/src/test/java/com/baeldung/jackson/xmlToJson/XmlToJsonUnitTest.java

@@ -0,0 +1,56 @@
+package com.baeldung.jackson.xmlToJson;
+
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.dataformat.xml.XmlMapper;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+import java.io.IOException;
+
+public class XmlToJsonUnitTest {
+
+    @Test
+    public void givenAnXML_whenUseDataBidingToConvertToJSON_thenReturnDataOK() {
+        String flowerXML = "<Flower><name>Poppy</name><color>RED</color><petals>9</petals></Flower>";
+
+        try {
+            XmlMapper xmlMapper = new XmlMapper();
+            Flower poppy = xmlMapper.readValue(flowerXML, Flower.class);
+
+            assertEquals(poppy.getName(), "Poppy");
+            assertEquals(poppy.getColor(), Color.RED);
+            assertEquals(poppy.getPetals(), new Integer(9));
+
+            ObjectMapper mapper = new ObjectMapper();
+            String json = mapper.writeValueAsString(poppy);
+
+            assertEquals(json, "{\"name\":\"Poppy\",\"color\":\"RED\",\"petals\":9}");
+            System.out.println(json);
+        } catch(IOException e) {
+            e.printStackTrace();
+        }
+    }
+
+    @Test
+    public void givenAnXML_whenUseATreeConvertToJSON_thenReturnDataOK() {
+        String flowerXML = "<Flower><name>Poppy</name><color>RED</color><petals>9</petals></Flower>";
+
+        try {
+            XmlMapper xmlMapper = new XmlMapper();
+            JsonNode node = xmlMapper.readTree(flowerXML.getBytes());
+
+            ObjectMapper jsonMapper = new ObjectMapper();
+            String json = jsonMapper.writeValueAsString(node);
+
+            System.out.println(json);
+
+            assertEquals(json, "{\"name\":\"Poppy\",\"color\":\"RED\",\"petals\":\"9\"}");
+        } catch(IOException e) {
+            e.printStackTrace();
+        }
+    }
+}

java-numbers/src/test/java/com/baeldung/maths/MathSinUnitTest.java

@@ -0,0 +1,20 @@
+package com.baeldung.maths;
+
+import static org.junit.Assert.assertTrue;
+
+import org.junit.jupiter.api.Test;
+
+public class MathSinUnitTest {
+
+    @Test
+    public void givenAnAngleInDegrees_whenUsingToRadians_thenResultIsInRadians() {
+        double angleInDegrees = 30;
+        double sinForDegrees = Math.sin(Math.toRadians(angleInDegrees)); // 0.5
+
+        double thirtyDegreesInRadians = 1/6 * Math.PI;
+        double sinForRadians = Math.sin(thirtyDegreesInRadians); // 0.5
+
+        assertTrue(sinForDegrees == sinForRadians);
+    }
+
+}

java-strings/README.md

@@ -28,6 +28,7 @@
 - [Java Check a String for Lowercase/Uppercase Letter, Special Character and Digit](https://www.baeldung.com/java-lowercase-uppercase-special-character-digit-regex)
 - [Convert java.util.Date to String](https://www.baeldung.com/java-util-date-to-string)
 - [String Not Empty Test Assertions in Java](https://www.baeldung.com/java-assert-string-not-empty)
+- [Get Substring from String in Java](https://www.baeldung.com/java-substring)
 - [Converting a Stack Trace to a String in Java](https://www.baeldung.com/java-stacktrace-to-string)
 - [Sorting a String Alphabetically in Java](https://www.baeldung.com/java-sort-string-alphabetically)
 - [Remove Emojis from a Java String](https://www.baeldung.com/java-string-remove-emojis)

jersey/README.md

@@ -1,3 +1,4 @@
 - [Jersey Filters and Interceptors](http://www.baeldung.com/jersey-filters-interceptors)
 - [Jersey MVC Support](https://www.baeldung.com/jersey-mvc)
+- [Bean Validation in Jersey](https://www.baeldung.com/jersey-bean-validation)
 - [Set a Response Body in JAX-RS](https://www.baeldung.com/jax-rs-response)

libraries-data/README.md

@@ -11,3 +11,4 @@
 - [Apache Ignite with Spring Data](http://www.baeldung.com/apache-ignite-spring-data)
 - [Guide to JMapper](https://www.baeldung.com/jmapper)
 - [A Guide to Apache Crunch](https://www.baeldung.com/apache-crunch)
+- [Building a Data Pipeline with Flink and Kafka](https://www.baeldung.com/kafka-flink-data-pipeline)

maven-polyglot/README.md

@@ -0,0 +1,3 @@
+To run the maven-polyglot-json-app successfully, you first have to build the maven-polyglot-json-extension module using: mvn clean install.
+
+Related Articles:

maven-polyglot/maven-polyglot-json-app/.mvn/extensions.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<extensions>
+    <extension>
+        <groupId>com.baeldung.maven.polyglot</groupId>
+        <artifactId>maven-polyglot-json-extension</artifactId>
+        <version>1.0-SNAPSHOT</version>
+    </extension>
+</extensions>

maven-polyglot/maven-polyglot-json-app/pom.json

@@ -0,0 +1,34 @@
+{
+  "modelVersion": "4.0.0",
+  "groupId": "com.baeldung.maven.polyglot",
+  "artifactId": "maven-polyglot-json-app",
+  "version": "1.0-SNAPSHOT",
+  "name": "Json Maven Polyglot",
+  "parent": {
+    "groupId": "org.springframework.boot",
+    "artifactId": "spring-boot-starter-parent",
+    "version": "2.0.5.RELEASE",
+    "relativePath": null
+  },
+  "properties": {
+    "project.build.sourceEncoding": "UTF-8",
+    "project.reporting.outputEncoding": "UTF-8",
+    "maven.compiler.source": "1.8",
+    "maven.compiler.target": "1.8",
+    "java.version": "1.8"
+  },
+  "dependencies": [
+    {
+      "groupId": "org.springframework.boot",
+      "artifactId": "spring-boot-starter-web"
+    }
+  ],
+  "build": {
+    "plugins": [
+      {
+        "groupId": "org.springframework.boot",
+        "artifactId": "spring-boot-maven-plugin"
+      }
+    ]
+  }
+}

maven-polyglot/maven-polyglot-json-app/src/main/java/com/baeldung/maven/polyglot/MavenPolyglotApplication.java

@@ -0,0 +1,19 @@
+package com.baeldung.maven.polyglot;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.bind.annotation.GetMapping;
+
+@RestController
+@SpringBootApplication
+public class MavenPolyglotApplication {
+    public static void main(String[] args) {
+        SpringApplication.run(MavenPolyglotApplication.class, args);
+    }
+
+    @GetMapping("/")
+    public String home(){
+        return "Hello JSON Maven Model !";
+    }
+}

maven-polyglot/maven-polyglot-json-app/src/main/resources/model.json

@@ -0,0 +1,109 @@
+{
+  "modules": [],
+  "distributionManagement": null,
+  "properties": {
+    "project.reporting.outputEncoding": "UTF-8",
+    "java.version": "1.8",
+    "maven.compiler.source": "1.8",
+    "project.build.sourceEncoding": "UTF-8",
+    "maven.compiler.target": "1.8"
+  },
+  "dependencyManagement": null,
+  "dependencies": [
+    {
+      "groupId": "org.springframework.boot",
+      "artifactId": "spring-boot-starter-web",
+      "version": null,
+      "type": "jar",
+      "classifier": null,
+      "scope": null,
+      "systemPath": null,
+      "exclusions": [],
+      "optional": null,
+      "managementKey": "org.springframework.boot:spring-boot-starter-web:jar"
+    }
+  ],
+  "repositories": [],
+  "pluginRepositories": [],
+  "reports": null,
+  "reporting": null,
+  "modelVersion": "4.0.0",
+  "parent": {
+    "groupId": "org.springframework.boot",
+    "artifactId": "spring-boot-starter-parent",
+    "version": "2.0.5.RELEASE",
+    "relativePath": "",
+    "id": "org.springframework.boot:spring-boot-starter-parent:pom:2.0.5.RELEASE"
+  },
+  "groupId": "com.demo.polyglot",
+  "artifactId": "maven-polyglot-app",
+  "version": "1.0.1",
+  "packaging": "jar",
+  "name": "Json Maven Polyglot",
+  "description": null,
+  "url": null,
+  "inceptionYear": null,
+  "organization": null,
+  "licenses": [],
+  "developers": [],
+  "contributors": [],
+  "mailingLists": [],
+  "prerequisites": null,
+  "scm": null,
+  "issueManagement": null,
+  "ciManagement": null,
+  "build": {
+    "plugins": [
+      {
+        "inherited": null,
+        "configuration": null,
+        "inheritanceApplied": true,
+        "groupId": "org.liquibase",
+        "artifactId": "liquibase-maven-plugin",
+        "version": "3.0.5",
+        "extensions": null,
+        "executions": [],
+        "dependencies": [],
+        "goals": null,
+        "key": "org.liquibase:liquibase-maven-plugin",
+        "id": "org.liquibase:liquibase-maven-plugin:3.0.5",
+        "executionsAsMap": {}
+      }
+    ],
+    "pluginManagement": null,
+    "defaultGoal": null,
+    "resources": [],
+    "testResources": [],
+    "directory": null,
+    "finalName": null,
+    "filters": [],
+    "sourceDirectory": null,
+    "scriptSourceDirectory": null,
+    "testSourceDirectory": null,
+    "outputDirectory": null,
+    "testOutputDirectory": null,
+    "extensions": [],
+    "pluginsAsMap": {
+      "org.liquibase:liquibase-maven-plugin": {
+        "inherited": null,
+        "configuration": null,
+        "inheritanceApplied": true,
+        "groupId": "org.liquibase",
+        "artifactId": "liquibase-maven-plugin",
+        "version": "3.0.5",
+        "extensions": null,
+        "executions": [],
+        "dependencies": [],
+        "goals": null,
+        "key": "org.liquibase:liquibase-maven-plugin",
+        "id": "org.liquibase:liquibase-maven-plugin:3.0.5",
+        "executionsAsMap": {}
+      }
+    }
+  },
+  "profiles": [],
+  "modelEncoding": "UTF-8",
+  "pomFile": null,
+  "id": "com.demo.polyglot:maven-polyglot-app:jar:1.0.1",
+  "projectDirectory": null
+}

maven-polyglot/maven-polyglot-json-extension/pom.xml

@@ -0,0 +1,47 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>com.baeldung.maven.polyglot</groupId>
+    <artifactId>maven-polyglot-json-extension</artifactId>
+    <version>1.0-SNAPSHOT</version>
+
+    <properties>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.maven</groupId>
+            <artifactId>maven-core</artifactId>
+            <version>3.5.4</version>
+            <scope>provided</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+            <version>2.9.6</version>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.codehaus.plexus</groupId>
+                <artifactId>plexus-component-metadata</artifactId>
+                <version>1.7.1</version>
+                <executions>
+                    <execution>
+                        <goals>
+                            <goal>generate-metadata</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>