Merge remote-tracking branch 'upstream/master'

persistence-modules/core-java-persistence/src/test/java/com/baeldung/jdbc/joins/ArticleWithAuthorDAOLiveTest.java

@@ -12,7 +12,7 @@ import java.util.List;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
-public class ArticleWithAuthorDAOIntegrationTest {
+public class ArticleWithAuthorDAOLiveTest {
         private Connection connection;
 
         private ArticleWithAuthorDAO articleWithAuthorDAO;

persistence-modules/deltaspike/pom.xml

@@ -317,7 +317,6 @@
         <war.plugin.version>2.6</war.plugin.version>
         <apt-maven-plugin.version>1.1.3</apt-maven-plugin.version>
         <jandex.version>1.2.5.Final-redhat-1</jandex.version>
-        <commons-lang3.version>3.5</commons-lang3.version>
     </properties>
 
 </project>

persistence-modules/elasticsearch/.gitignore

@@ -0,0 +1,29 @@
+HELP.md
+/target/
+!.mvn/wrapper/maven-wrapper.jar
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+/build/
+
+### VS Code ###
+.vscode/

persistence-modules/elasticsearch/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles
+
+- [Jest – Elasticsearch Java Client](https://www.baeldung.com/elasticsearch-jest)

persistence-modules/elasticsearch/pom.xml

@@ -0,0 +1,35 @@
+<?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</groupId>
+    <artifactId>elasticsearch</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>elasticsearch</name>
+    <description>Demo project for Java Elasticsearch libraries</description>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+        <relativePath>../../</relativePath>
+    </parent>
+
+    <dependencies>
+
+        <dependency>
+            <groupId>io.searchbox</groupId>
+            <artifactId>jest</artifactId>
+            <version>${jest.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+            <version>${jackson.version}</version>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <jest.version>6.3.1</jest.version>
+    </properties>
+</project>

persistence-modules/elasticsearch/src/main/java/com/baeldung/jest/Employee.java

@@ -0,0 +1,42 @@
+package com.baeldung.jest;
+
+import java.util.List;
+
+public class Employee {
+    String name;
+    String title;
+    List<String> skills;
+    int yearsOfService;
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public List<String> getSkills() {
+        return skills;
+    }
+
+    public void setSkills(List<String> skills) {
+        this.skills = skills;
+    }
+
+    public int getYearsOfService() {
+        return yearsOfService;
+    }
+
+    public void setYearsOfService(int yearsOfService) {
+        this.yearsOfService = yearsOfService;
+    }
+}

persistence-modules/elasticsearch/src/main/java/com/baeldung/jest/JestDemoApplication.java

@@ -0,0 +1,174 @@
+package com.baeldung.jest;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import io.searchbox.client.JestClient;
+import io.searchbox.client.JestClientFactory;
+import io.searchbox.client.JestResult;
+import io.searchbox.client.JestResultHandler;
+import io.searchbox.client.config.HttpClientConfig;
+import io.searchbox.core.*;
+import io.searchbox.indices.CreateIndex;
+import io.searchbox.indices.IndicesExists;
+import io.searchbox.indices.aliases.AddAliasMapping;
+import io.searchbox.indices.aliases.ModifyAliases;
+import io.searchbox.indices.aliases.RemoveAliasMapping;
+
+import java.io.IOException;
+import java.util.*;
+
+public class JestDemoApplication {
+
+    public static void main(String[] args) throws IOException {
+
+        // Demo the JestClient
+        JestClient jestClient = jestClient();
+
+        // Check an index
+        JestResult result = jestClient.execute(new IndicesExists.Builder("employees").build());
+        if(!result.isSucceeded()) {
+            System.out.println(result.getErrorMessage());
+        }
+
+        // Create an index
+        jestClient.execute(new CreateIndex.Builder("employees").build());
+
+        // Create an index with options
+        Map<String, Object> settings = new HashMap<>();
+        settings.put("number_of_shards", 11);
+        settings.put("number_of_replicas", 2);
+        jestClient.execute(new CreateIndex.Builder("employees").settings(settings).build());
+
+        // Create an alias, then remove it
+        jestClient.execute(new ModifyAliases.Builder(
+                new AddAliasMapping.Builder(
+                        "employees",
+                        "e")
+                        .build())
+                .build());
+        JestResult jestResult = jestClient.execute(new ModifyAliases.Builder(
+                new RemoveAliasMapping.Builder(
+                        "employees",
+                        "e")
+                        .build())
+                .build());
+
+        if(jestResult.isSucceeded()) {
+            System.out.println("Success!");
+        }
+        else {
+            System.out.println(jestResult.getErrorMessage());
+        }
+
+        // Sample JSON for indexing
+
+        // {
+        //  "name": "Michael Pratt",
+        //  "title": "Java Developer",
+        //  "skills": ["java", "spring", "elasticsearch"],
+        //  "yearsOfService": 2
+        // }
+
+        // Index a document from String
+        ObjectMapper mapper = new ObjectMapper();
+        JsonNode employeeJsonNode = mapper.createObjectNode()
+                .put("name", "Michael Pratt")
+                .put("title", "Java Developer")
+                .put("yearsOfService", 2)
+                .set("skills", mapper.createArrayNode()
+                        .add("java")
+                        .add("spring")
+                        .add("elasticsearch"));
+        jestClient.execute(new Index.Builder(employeeJsonNode.toString()).index("employees").build());
+
+        // Index a document from Map
+        Map<String, Object> employeeHashMap = new LinkedHashMap<>();
+        employeeHashMap.put("name", "Michael Pratt");
+        employeeHashMap.put("title", "Java Developer");
+        employeeHashMap.put("yearsOfService", 2);
+        employeeHashMap.put("skills", Arrays.asList("java", "spring", "elasticsearch"));
+        jestClient.execute(new Index.Builder(employeeHashMap).index("employees").build());
+
+        // Index a document from POJO
+        Employee employee = new Employee();
+        employee.setName("Michael Pratt");
+        employee.setTitle("Java Developer");
+        employee.setYearsOfService(2);
+        employee.setSkills(Arrays.asList("java", "spring", "elasticsearch"));
+        jestClient.execute(new Index.Builder(employee).index("employees").build());
+
+        // Read document by ID
+        Employee getResult = jestClient.execute(new Get.Builder("employees", "1").build()).getSourceAsObject(Employee.class);
+
+        // Search documents
+        String search = "{\n" +
+                "  \"query\": {\n" +
+                "    \"bool\": {\n" +
+                "      \"must\": [\n" +
+                "        { \"match\": { \"name\":   \"Michael Pratt\" }}\n" +
+                "      ]\n" +
+                "    }\n" +
+                "  }\n" +
+                "}";
+        List<SearchResult.Hit<Employee, Void>> searchResults =
+           jestClient.execute(new Search.Builder(search).build())
+           .getHits(Employee.class);
+
+        searchResults.forEach(hit -> {
+            System.out.println(String.format("Document %s has score %s", hit.id, hit.score));
+        });
+
+        // Update document
+        employee.setYearsOfService(3);
+        jestClient.execute(new Update.Builder(employee).index("employees").id("1").build());
+
+        // Delete documents
+        jestClient.execute(new Delete.Builder("2") .index("employees") .build());
+
+        // Bulk operations
+        Employee employeeObject1 = new Employee();
+        employee.setName("John Smith");
+        employee.setTitle("Python Developer");
+        employee.setYearsOfService(10);
+        employee.setSkills(Arrays.asList("python"));
+
+        Employee employeeObject2 = new Employee();
+        employee.setName("Kate Smith");
+        employee.setTitle("Senior JavaScript Developer");
+        employee.setYearsOfService(10);
+        employee.setSkills(Arrays.asList("javascript", "angular"));
+
+        jestClient.execute(new Bulk.Builder().defaultIndex("employees")
+                .addAction(new Index.Builder(employeeObject1).build())
+                .addAction(new Index.Builder(employeeObject2).build())
+                .addAction(new Delete.Builder("3").build()) .build());
+
+        // Async operations
+        Employee employeeObject3 = new Employee();
+        employee.setName("Jane Doe");
+        employee.setTitle("Manager");
+        employee.setYearsOfService(20);
+        employee.setSkills(Arrays.asList("managing"));
+
+        jestClient.executeAsync( new Index.Builder(employeeObject3).build(), new JestResultHandler<JestResult>() {
+            @Override public void completed(JestResult result) {
+                // handle result
+            }
+            @Override public void failed(Exception ex) {
+                // handle exception
+            }
+        });
+    }
+
+    private static JestClient jestClient()
+    {
+        JestClientFactory factory = new JestClientFactory();
+        factory.setHttpClientConfig(
+           new HttpClientConfig.Builder("http://localhost:9200")
+              .multiThreaded(true)
+              .defaultMaxTotalConnectionPerRoute(2)
+              .maxTotalConnection(20)
+              .build());
+        return factory.getObject();
+    }
+}

persistence-modules/hibernate-mapping/README.md

@@ -3,3 +3,5 @@
 
 - [Persisting Maps with Hibernate](https://www.baeldung.com/hibernate-persisting-maps)
 - [Difference Between @Size, @Length, and @Column(length=value)](https://www.baeldung.com/jpa-size-length-column-differences)
+- [Hibernate Validator Specific Constraints](https://www.baeldung.com/hibernate-validator-constraints)
+- [Hibernate One to Many Annotation Tutorial](http://www.baeldung.com/hibernate-one-to-many)

persistence-modules/hibernate-mapping/pom.xml

@@ -2,6 +2,9 @@
 <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">
+    <artifactId>hibernate-mapping</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+    <modelVersion>4.0.0</modelVersion>
 
     <parent>
         <groupId>com.baeldung</groupId>
@@ -10,10 +13,6 @@
         <relativePath>..</relativePath>
     </parent>
 
-    <artifactId>hibernate-mapping</artifactId>
-    <version>1.0.0-SNAPSHOT</version>
-    <modelVersion>4.0.0</modelVersion>
-
     <dependencies>
         <dependency>
             <groupId>org.hibernate</groupId>
@@ -45,12 +44,12 @@
         <dependency>
             <groupId>javax.money</groupId>
             <artifactId>money-api</artifactId>
-            <version>1.0.3</version>
+            <version>${money-api.version}</version>
         </dependency>
         <dependency>
             <groupId>org.javamoney</groupId>
             <artifactId>moneta</artifactId>
-            <version>1.3</version>
+            <version>${moneta.version}</version>
             <type>pom</type>
         </dependency>
     </dependencies>
@@ -59,7 +58,7 @@
         <finalName>hibernate-mapping</finalName>
         <resources>
             <resource>
-                <directory>src/test/resources</directory>
+                <directory>src/main/resources</directory>
                 <filtering>true</filtering>
             </resource>
         </resources>
@@ -70,6 +69,8 @@
         <assertj-core.version>3.8.0</assertj-core.version>
         <hibernate-validator.version>6.0.16.Final</hibernate-validator.version>
         <org.glassfish.javax.el.version>3.0.1-b11</org.glassfish.javax.el.version>
+        <money-api.version>1.0.3</money-api.version>
+        <moneta.version>1.3</moneta.version>
     </properties>
 
 </project>

persistence-modules/hibernate-mapping/src/main/java/com/baeldung/hibernate/oneToMany/config/HibernateAnnotationUtil.java

@@ -1,8 +1,9 @@
 package com.baeldung.hibernate.oneToMany.config;
 
 import org.hibernate.SessionFactory;
+import org.hibernate.boot.Metadata;
+import org.hibernate.boot.MetadataSources;
 import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
-import org.hibernate.cfg.Configuration;
 import org.hibernate.service.ServiceRegistry;
 
 public class HibernateAnnotationUtil {
@@ -12,16 +13,12 @@ public class HibernateAnnotationUtil {
     private static SessionFactory buildSessionFactory() {
         try {
             // Create the SessionFactory from hibernate-annotation.cfg.xml
-            Configuration configuration = new Configuration();
-            configuration.configure("hibernate-annotation.cfg.xml");
-            System.out.println("Hibernate Annotation Configuration loaded");
-
-            ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties()).build();
-            System.out.println("Hibernate Annotation serviceRegistry created");
-
-            SessionFactory sessionFactory = configuration.buildSessionFactory(serviceRegistry);
+            ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder().configure("hibernate-annotation.cfg.xml").build();
+            Metadata metadata = new MetadataSources(serviceRegistry).getMetadataBuilder().build();
+            SessionFactory sessionFactory = metadata.getSessionFactoryBuilder().build();
 
             return sessionFactory;
+
         } catch (Throwable ex) {
             System.err.println("Initial SessionFactory creation failed." + ex);
             ex.printStackTrace();

persistence-modules/hibernate-mapping/src/main/resources/hibernate-annotation.cfg.xml

@@ -4,11 +4,11 @@
 		"http://hibernate.org/dtd/hibernate-configuration-3.0.dtd">
 <hibernate-configuration>
     <session-factory>
-        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
-        <property name="hibernate.connection.password">mypassword</property>
-        <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/spring_hibernate_one_to_many?createDatabaseIfNotExist=true</property>
-        <property name="hibernate.connection.username">myuser</property>
-        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
+        <property name="hibernate.connection.driver_class">org.h2.Driver</property>
+        <property name="hibernate.connection.password"></property>
+        <property name="hibernate.connection.url">jdbc:h2:mem:spring_hibernate_one_to_many</property>
+        <property name="hibernate.connection.username">sa</property>
+        <property name="hibernate.dialect">org.hibernate.dialect.H2Dialect</property>
         <property name="hbm2ddl.auto">create</property>
         <property name="hibernate.current_session_context_class">thread</property>
         <property name="hibernate.show_sql">true</property>

persistence-modules/hibernate-mapping/src/test/java/com/baeldung/hibernate/oneToMany/main/HibernateOneToManyAnnotationMainIntegrationTest.java

@@ -10,7 +10,7 @@ import org.hibernate.Session;
 import org.hibernate.SessionFactory;
 import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
 import org.hibernate.cfg.Configuration;
-import org.hibernate.dialect.HSQLDialect;
+import org.hibernate.dialect.H2Dialect;
 import org.hibernate.service.ServiceRegistry;
 import org.junit.After;
 import org.junit.AfterClass;
@@ -18,6 +18,7 @@ import org.junit.Assert;
 import org.junit.Before;
 import org.junit.BeforeClass;
 import org.junit.Test;
+
 import com.baeldung.hibernate.oneToMany.model.Cart;
 import com.baeldung.hibernate.oneToMany.model.Items;
 
@@ -33,9 +34,9 @@ public class HibernateOneToManyAnnotationMainIntegrationTest {
 	@BeforeClass
 	public static void beforeTests() {
 		Configuration configuration = new Configuration().addAnnotatedClass(Cart.class).addAnnotatedClass(Items.class)
-				.setProperty("hibernate.dialect", HSQLDialect.class.getName())
-				.setProperty("hibernate.connection.driver_class", org.hsqldb.jdbcDriver.class.getName())
-				.setProperty("hibernate.connection.url", "jdbc:hsqldb:mem:test")
+				.setProperty("hibernate.dialect", H2Dialect.class.getName())
+				.setProperty("hibernate.connection.driver_class", org.h2.Driver.class.getName())
+				.setProperty("hibernate.connection.url", "jdbc:h2:mem:test")
 				.setProperty("hibernate.connection.username", "sa").setProperty("hibernate.connection.password", "")
 				.setProperty("hibernate.hbm2ddl.auto", "update");
 		ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()

persistence-modules/hibernate-ogm/pom.xml

@@ -19,31 +19,31 @@
 		<dependency>
 			<groupId>org.hibernate.ogm</groupId>
 			<artifactId>hibernate-ogm-mongodb</artifactId>
-			<version>5.4.0.Final</version>
+			<version>${hibernate.version}</version>
 		</dependency>
 		<!-- Neo4j -->
 		<dependency>
 			<groupId>org.hibernate.ogm</groupId>
 			<artifactId>hibernate-ogm-neo4j</artifactId>
-			<version>5.4.0.Final</version>
+			<version>${hibernate.version}</version>
 		</dependency>
 		<!-- Narayana JTA -->  
 		<dependency>
 			<groupId>org.jboss.narayana.jta</groupId>
 			<artifactId>narayana-jta</artifactId>
-			<version>5.5.23.Final</version>
+			<version>${narayana-jta.version}</version>
 		</dependency>
 		<!-- Testing -->
 		<dependency>
 			<groupId>junit</groupId>
 			<artifactId>junit</artifactId>
-			<version>4.12</version>
+			<version>${junit.version}</version>
 			<scope>test</scope>
 		</dependency>
 		<dependency>
 			<groupId>org.easytesting</groupId>
 			<artifactId>fest-assert</artifactId>
-			<version>1.4</version>
+			<version>${fest-assert.version}</version>
 			<scope>test</scope>
 		</dependency>
     </dependencies>
@@ -57,4 +57,10 @@
             </resource>
         </resources>
     </build>
+
+    <properties>
+        <hibernate.version>5.4.0.Final</hibernate.version>
+        <fest-assert.version>1.4</fest-assert.version>
+        <narayana-jta.version>5.5.23.Final</narayana-jta.version>
+    </properties>
 </project>

persistence-modules/hibernate5/README.md

@@ -33,3 +33,4 @@
 - [Hibernate Aggregate Functions](https://www.baeldung.com/hibernate-aggregate-functions)
 - [Hibernate Query Plan Cache](https://www.baeldung.com/hibernate-query-plan-cache)
 - [TransactionRequiredException Error](https://www.baeldung.com/jpa-transaction-required-exception)
+- [Enabling Transaction Locks in Spring Data JPA](https://www.baeldung.com/java-jpa-transaction-locks)

persistence-modules/hibernate5/pom.xml

@@ -60,7 +60,7 @@
         <dependency>
             <groupId>org.hibernate</groupId>
             <artifactId>hibernate-testing</artifactId>
-            <version>5.2.2.Final</version>
+            <version>${hibernate.version}</version>
         </dependency>
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>
@@ -70,7 +70,7 @@
         <dependency>
             <groupId>net.bytebuddy</groupId>
             <artifactId>byte-buddy</artifactId>
-            <version>1.9.5</version>
+            <version>${byte-buddy.version}</version>
         </dependency>
 
         <dependency>
@@ -91,7 +91,7 @@
         <dependency>
             <groupId>javax.xml.bind</groupId>
             <artifactId>jaxb-api</artifactId>
-            <version>2.3.0</version>
+            <version>${jaxb-api.version}</version>
         </dependency>
     </dependencies>
 
@@ -120,6 +120,8 @@
         <assertj-core.version>3.8.0</assertj-core.version>
         <openjdk-jmh.version>1.21</openjdk-jmh.version>
         <geodb.version>0.9</geodb.version>
+        <byte-buddy.version>1.9.5</byte-buddy.version>
+        <jaxb-api.version>2.3.0</jaxb-api.version>
     </properties>
 
 </project>

persistence-modules/java-cassandra/pom.xml

@@ -39,6 +39,7 @@
         <!-- Cassandra -->
         <cassandra-driver-core.version>3.1.2</cassandra-driver-core.version>
         <cassandra-unit.version>3.1.1.0</cassandra-unit.version>
+        <guava.version>18.0</guava.version>
     </properties>
 
 </project>

persistence-modules/java-jpa-2/README.md

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

persistence-modules/java-jpa-2/pom.xml

@@ -0,0 +1,115 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>java-jpa-2</artifactId>
+    <name>java-jpa-2</name>
+
+    <parent>
+        <artifactId>parent-modules</artifactId>
+        <groupId>com.baeldung</groupId>
+        <version>1.0.0-SNAPSHOT</version>
+        <relativePath>../../pom.xml</relativePath>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.hibernate</groupId>
+            <artifactId>hibernate-core</artifactId>
+            <version>${hibernate.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.hibernate</groupId>
+            <artifactId>hibernate-jpamodelgen</artifactId>
+            <version>${hibernate.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.h2database</groupId>
+            <artifactId>h2</artifactId>
+            <version>${h2.version}</version>
+        </dependency>
+
+        <!--Compile time JPA API-->
+        <dependency>
+            <groupId>javax.persistence</groupId>
+            <artifactId>javax.persistence-api</artifactId>
+            <version>${javax.persistence-api.version}</version>
+        </dependency>
+
+        <!--Runtime JPA implementation-->
+        <dependency>
+            <groupId>org.eclipse.persistence</groupId>
+            <artifactId>eclipselink</artifactId>
+            <version>${eclipselink.version}</version>
+            <scope>runtime</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.postgresql</groupId>
+            <artifactId>postgresql</artifactId>
+            <version>${postgres.version}</version>
+            <scope>runtime</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.5.1</version>
+                <configuration>
+                    <compilerArgument>-proc:none</compilerArgument>
+                </configuration>
+            </plugin>
+            <plugin>
+                <groupId>org.bsc.maven</groupId>
+                <artifactId>maven-processor-plugin</artifactId>
+                <version>3.3.3</version>
+                <executions>
+                    <execution>
+                        <id>process</id>
+                        <goals>
+                            <goal>process</goal>
+                        </goals>
+                        <phase>generate-sources</phase>
+                        <configuration>
+                            <outputDirectory>target/metamodel</outputDirectory>
+                            <processors>
+                                <processor>org.hibernate.jpamodelgen.JPAMetaModelEntityProcessor</processor>
+                            </processors>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+
+            <plugin>
+                <groupId>org.codehaus.mojo</groupId>
+                <artifactId>build-helper-maven-plugin</artifactId>
+                <version>3.0.0</version>
+                <executions>
+                    <execution>
+                        <id>add-source</id>
+                        <phase>generate-sources</phase>
+                        <goals>
+                            <goal>add-source</goal>
+                        </goals>
+                        <configuration>
+                            <sources>
+                                <source>target/metamodel</source>
+                            </sources>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+        </plugins>
+    </build>
+
+    <properties>
+        <hibernate.version>5.4.0.Final</hibernate.version>
+        <eclipselink.version>2.7.4-RC1</eclipselink.version>
+        <postgres.version>42.2.5</postgres.version>
+        <javax.persistence-api.version>2.2</javax.persistence-api.version>
+    </properties>
+
+</project>

persistence-modules/java-jpa-2/src/main/java/com/baeldung/jpa/entity/Article.java

@@ -0,0 +1,12 @@
+package com.baeldung.jpa.entity;
+
+import javax.persistence.Entity;
+import javax.persistence.Table;
+
+@Entity(name = "MyArticle")
+@Table(name = Article.TABLE_NAME)
+public class Article {
+
+    public static final String TABLE_NAME = "ARTICLES";
+
+}

persistence-modules/java-jpa/README.md

@@ -8,6 +8,9 @@
 - [Converting Between LocalDate and SQL Date](https://www.baeldung.com/java-convert-localdate-sql-date)
 - [Combining JPA And/Or Criteria Predicates](https://www.baeldung.com/jpa-and-or-criteria-predicates)
 - [Types of JPA Queries](https://www.baeldung.com/jpa-queries)
+- [JPA/Hibernate Projections](https://www.baeldung.com/jpa-hibernate-projections)
+- [Composite Primary Keys in JPA](https://www.baeldung.com/jpa-composite-primary-keys)
 - [Defining JPA Entities](https://www.baeldung.com/jpa-entities)
 - [JPA @Basic Annotation](https://www.baeldung.com/jpa-basic-annotation)
 - [Default Column Values in JPA](https://www.baeldung.com/jpa-default-column-values)
+- [Persisting Enums in JPA](https://www.baeldung.com/jpa-persisting-enums-in-jpa)

persistence-modules/java-jpa/pom.xml

@@ -19,6 +19,11 @@
             <artifactId>hibernate-core</artifactId>
             <version>${hibernate.version}</version>
         </dependency>
+		<dependency>
+			<groupId>org.hibernate</groupId>
+			<artifactId>hibernate-jpamodelgen</artifactId>
+			<version>${hibernate.version}</version>
+		</dependency>
         <dependency>
             <groupId>com.h2database</groupId>
             <artifactId>h2</artifactId>
@@ -29,7 +34,7 @@
         <dependency>
             <groupId>javax.persistence</groupId>
             <artifactId>javax.persistence-api</artifactId>
-            <version>2.2</version>
+            <version>${javax.persistence-api.version}</version>
         </dependency>
 
         <!--Runtime JPA implementation-->
@@ -47,10 +52,64 @@
         </dependency>
     </dependencies>
 
+	<build>
+		<plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.5.1</version>
+                <configuration>
+                    <compilerArgument>-proc:none</compilerArgument>
+                </configuration>
+            </plugin>
+			<plugin>
+				<groupId>org.bsc.maven</groupId>
+				<artifactId>maven-processor-plugin</artifactId>
+				<version>3.3.3</version>
+				<executions>
+					<execution>
+						<id>process</id>
+						<goals>
+							<goal>process</goal>
+						</goals>
+						<phase>generate-sources</phase>
+						<configuration>
+							<outputDirectory>target/metamodel</outputDirectory>
+							<processors>
+								<processor>org.hibernate.jpamodelgen.JPAMetaModelEntityProcessor</processor>
+							</processors>
+						</configuration>
+					</execution>
+				</executions>
+			</plugin>
+
+			<plugin>
+				<groupId>org.codehaus.mojo</groupId>
+				<artifactId>build-helper-maven-plugin</artifactId>
+				<version>3.0.0</version>
+				<executions>
+					<execution>
+						<id>add-source</id>
+						<phase>generate-sources</phase>
+						<goals>
+							<goal>add-source</goal>
+						</goals>
+						<configuration>
+							<sources>
+								<source>target/metamodel</source>
+							</sources>
+						</configuration>
+					</execution>
+				</executions>
+			</plugin>
+		</plugins>
+	</build>
+
     <properties>
         <hibernate.version>5.4.0.Final</hibernate.version>
         <eclipselink.version>2.7.4-RC1</eclipselink.version>
         <postgres.version>42.2.5</postgres.version>
+        <javax.persistence-api.version>2.2</javax.persistence-api.version>
     </properties>
 
 </project>

persistence-modules/java-jpa/src/main/java/com/baeldung/jpa/queryparams/Employee.java

@@ -0,0 +1,79 @@
+package com.baeldung.jpa.queryparams;
+
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.Table;
+
+@Entity
+@Table(name = "employees")
+public class Employee {
+
+    /**
+     * 
+     */
+    private static final long serialVersionUID = 1L;
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    @Column(name = "id")
+    private Long id;
+
+    @Column(name = "employee_number", unique = true)
+    private String empNumber;
+
+    @Column(name = "employee_name")
+    private String name;
+
+    @Column(name = "employee_age")
+    private int age;
+
+    public Employee() {
+        super();
+    }
+
+    public Employee(Long id, String empNumber) {
+        super();
+        this.id = id;
+        this.empNumber = empNumber;
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public int getAge() {
+        return age;
+    }
+
+    public void setAge(int age) {
+        this.age = age;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getEmpNumber() {
+        return empNumber;
+    }
+
+    public void setEmpNumber(String empNumber) {
+        this.empNumber = empNumber;
+    }
+
+    public static long getSerialversionuid() {
+        return serialVersionUID;
+    }
+
+}

persistence-modules/java-jpa/src/main/resources/META-INF/persistence.xml

@@ -224,4 +224,26 @@
 				value="products_jpa.sql" />
 		</properties>
 	</persistence-unit>
+	
+	<persistence-unit name="jpa-h2-queryparams" transaction-type="RESOURCE_LOCAL">
+		<provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
+		<class>com.baeldung.jpa.queryparams.Employee</class>
+		<exclude-unlisted-classes>true</exclude-unlisted-classes>
+		<properties>
+			<property name="javax.persistence.jdbc.driver"
+				value="org.h2.Driver" />
+			<property name="javax.persistence.jdbc.url"
+				value="jdbc:h2:mem:test" />
+			<property name="javax.persistence.jdbc.user" value="sa" />
+			<property name="javax.persistence.jdbc.password" value="" />
+			<property name="hibernate.dialect"
+				value="org.hibernate.dialect.H2Dialect" />
+			<property name="hibernate.hbm2ddl.auto" value="create-drop" />
+			<property name="show_sql" value="true" />
+			<property name="hibernate.temp.use_jdbc_metadata_defaults"
+				value="false" />
+			<property name="javax.persistence.sql-load-script-source"
+				value="employees2.sql" />
+		</properties>
+	</persistence-unit>
 </persistence>

persistence-modules/java-jpa/src/test/java/com/baeldung/jpa/queryparams/JPAQueryParamsUnitTest.java

@@ -0,0 +1,109 @@
+package com.baeldung.jpa.queryparams;
+
+import java.util.Arrays;
+import java.util.List;
+
+import javax.persistence.EntityManager;
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.Persistence;
+import javax.persistence.TypedQuery;
+import javax.persistence.criteria.CriteriaBuilder;
+import javax.persistence.criteria.CriteriaQuery;
+import javax.persistence.criteria.ParameterExpression;
+import javax.persistence.criteria.Root;
+
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+/**
+ * JPAQueryParamsTest class tests.
+ *
+ * @author gmlopez.mackinnon@gmail.com
+ */
+public class JPAQueryParamsUnitTest {
+
+    private static EntityManager entityManager;
+
+    @BeforeClass
+    public static void setup() {
+        EntityManagerFactory factory = Persistence.createEntityManagerFactory("jpa-h2-queryparams");
+        entityManager = factory.createEntityManager();
+    }
+
+    @Test
+    public void givenEmpNumber_whenUsingPositionalParameter_thenReturnExpectedEmployee() {
+        TypedQuery<Employee> query = entityManager.createQuery("SELECT e FROM Employee e WHERE e.empNumber = ?1", Employee.class);
+        String empNumber = "A123";
+        Employee employee = query.setParameter(1, empNumber)
+            .getSingleResult();
+        Assert.assertNotNull("Employee not found", employee);
+    }
+
+    @Test
+    public void givenEmpNumberList_whenUsingPositionalParameter_thenReturnExpectedEmployee() {
+        TypedQuery<Employee> query = entityManager.createQuery("SELECT e FROM Employee e WHERE e.empNumber IN (?1)", Employee.class);
+        List<String> empNumbers = Arrays.asList("A123", "A124");
+        List<Employee> employees = query.setParameter(1, empNumbers)
+            .getResultList();
+        Assert.assertNotNull("Employees not found", employees);
+        Assert.assertFalse("Employees not found", employees.isEmpty());
+    }
+
+    @Test
+    public void givenEmpNumber_whenUsingNamedParameter_thenReturnExpectedEmployee() {
+        TypedQuery<Employee> query = entityManager.createQuery("SELECT e FROM Employee e WHERE e.empNumber = :number", Employee.class);
+        String empNumber = "A123";
+        Employee employee = query.setParameter("number", empNumber)
+            .getSingleResult();
+        Assert.assertNotNull("Employee not found", employee);
+    }
+
+    @Test
+    public void givenEmpNumberList_whenUsingNamedParameter_thenReturnExpectedEmployee() {
+        TypedQuery<Employee> query = entityManager.createQuery("SELECT e FROM Employee e WHERE e.empNumber IN (:numbers)", Employee.class);
+        List<String> empNumbers = Arrays.asList("A123", "A124");
+        List<Employee> employees = query.setParameter("numbers", empNumbers)
+            .getResultList();
+        Assert.assertNotNull("Employees not found", employees);
+        Assert.assertFalse("Employees not found", employees.isEmpty());
+    }
+
+    @Test
+    public void givenEmpNameAndEmpAge_whenUsingTwoNamedParameters_thenReturnExpectedEmployees() {
+        TypedQuery<Employee> query = entityManager.createQuery("SELECT e FROM Employee e WHERE e.name = :name AND e.age = :empAge", Employee.class);
+        String empName = "John Doe";
+        int empAge = 55;
+        List<Employee> employees = query.setParameter("name", empName)
+            .setParameter("empAge", empAge)
+            .getResultList();
+        Assert.assertNotNull("Employees not found!", employees);
+        Assert.assertTrue("Employees not found!", !employees.isEmpty());
+    }
+
+    @Test
+    public void givenEmpNumber_whenUsingCriteriaQuery_thenReturnExpectedEmployee() {
+        CriteriaBuilder cb = entityManager.getCriteriaBuilder();
+
+        CriteriaQuery<Employee> cQuery = cb.createQuery(Employee.class);
+        Root<Employee> c = cQuery.from(Employee.class);
+        ParameterExpression<String> paramEmpNumber = cb.parameter(String.class);
+        cQuery.select(c)
+            .where(cb.equal(c.get(Employee_.empNumber), paramEmpNumber));
+
+        TypedQuery<Employee> query = entityManager.createQuery(cQuery);
+        String empNumber = "A123";
+        query.setParameter(paramEmpNumber, empNumber);
+        Employee employee = query.getSingleResult();
+        Assert.assertNotNull("Employee not found!", employee);
+    }
+
+    @Test
+    public void givenEmpNumber_whenUsingLiteral_thenReturnExpectedEmployee() {
+        String empNumber = "A123";
+        TypedQuery<Employee> query = entityManager.createQuery("SELECT e FROM Employee e WHERE e.empNumber = '" + empNumber + "'", Employee.class);
+        Employee employee = query.getSingleResult();
+        Assert.assertNotNull("Employee not found!", employee);
+    }
+
+}

persistence-modules/java-jpa/src/test/resources/employees2.sql

@@ -0,0 +1,2 @@
+INSERT INTO employees (employee_number, employee_name, employee_age) VALUES ('111', 'John Doe', 55);
+INSERT INTO employees (employee_number, employee_name, employee_age) VALUES ('A123', 'John Doe Junior', 25);

persistence-modules/java-mongodb/pom.xml

@@ -1,42 +1,49 @@
 <?xml version="1.0"?>
-<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" xmlns="http://maven.apache.org/POM/4.0.0"
-    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
-    <modelVersion>4.0.0</modelVersion>
-    <groupId>com.baeldung</groupId>
-    <artifactId>java-mongodb</artifactId>
-    <version>1.0-SNAPSHOT</version>
+<project
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"
+	xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>com.baeldung</groupId>
+	<artifactId>java-mongodb</artifactId>
+	<version>1.0-SNAPSHOT</version>
 	<name>java-mongodb</name>
 
-    <parent>
-        <groupId>com.baeldung</groupId>
-        <artifactId>parent-modules</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
-        <relativePath>../../</relativePath>
-    </parent>
+	<parent>
+		<groupId>com.baeldung</groupId>
+		<artifactId>parent-modules</artifactId>
+		<version>1.0.0-SNAPSHOT</version>
+		<relativePath>../../</relativePath>
+	</parent>
 
-    <dependencies>
+	<dependencies>
 
-        <dependency>
-            <groupId>de.flapdoodle.embedmongo</groupId>
-            <artifactId>de.flapdoodle.embedmongo</artifactId>
-            <version>${flapdoodle.version}</version>
-            <scope>test</scope>
-        </dependency>
+		<dependency>
+			<groupId>de.flapdoodle.embedmongo</groupId>
+			<artifactId>de.flapdoodle.embedmongo</artifactId>
+			<version>${flapdoodle.version}</version>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.mongodb</groupId>
+			<artifactId>mongo-java-driver</artifactId>
+			<version>${mongo.version}</version>
+		</dependency>
 
+		<dependency>
+			<groupId>dev.morphia.morphia</groupId>
+			<artifactId>core</artifactId>
+			<version>${morphia.version}</version>
+		</dependency>
 
-        <dependency>
-            <groupId>org.mongodb</groupId>
-            <artifactId>mongo-java-driver</artifactId>
-            <version>${mongo.version}</version>
-        </dependency>
+	</dependencies>
 
-    </dependencies>
-
-    <properties>
-        <maven.compiler.source>1.8</maven.compiler.source>
-        <maven.compiler.target>1.8</maven.compiler.target>
-        <mongo.version>3.10.1</mongo.version>
-        <flapdoodle.version>1.11</flapdoodle.version>
-    </properties>
+	<properties>
+		<maven.compiler.source>1.8</maven.compiler.source>
+		<maven.compiler.target>1.8</maven.compiler.target>
+		<mongo.version>3.10.1</mongo.version>
+		<flapdoodle.version>1.11</flapdoodle.version>
+		<morphia.version>1.5.3</morphia.version>
+	</properties>
 
 </project>

persistence-modules/java-mongodb/src/main/java/com/baeldung/morphia/domain/Author.java

@@ -0,0 +1,31 @@
+package com.baeldung.morphia.domain;
+
+import java.util.List;
+
+import dev.morphia.annotations.Entity;
+import dev.morphia.annotations.Id;
+
+@Entity
+public class Author {
+
+    @Id
+    private String name;
+    private List<String> books;
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public List<String> getBooks() {
+        return books;
+    }
+
+    public void setBooks(List<String> books) {
+        this.books = books;
+    }
+
+}

persistence-modules/java-mongodb/src/main/java/com/baeldung/morphia/domain/Book.java

@@ -0,0 +1,116 @@
+package com.baeldung.morphia.domain;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import dev.morphia.annotations.Embedded;
+import dev.morphia.annotations.Entity;
+import dev.morphia.annotations.Field;
+import dev.morphia.annotations.Id;
+import dev.morphia.annotations.Index;
+import dev.morphia.annotations.IndexOptions;
+import dev.morphia.annotations.Indexes;
+import dev.morphia.annotations.Property;
+import dev.morphia.annotations.Reference;
+import dev.morphia.annotations.Validation;
+
+@Entity("Books")
+@Indexes({ @Index(fields = @Field("title"), options = @IndexOptions(name = "book_title")) })
+@Validation("{ price : { $gt : 0 } }")
+public class Book {
+    @Id
+    private String isbn;
+    @Property
+    private String title;
+    private String author;
+    @Embedded
+    private Publisher publisher;
+    @Property("price")
+    private double cost;
+    @Reference
+    private Set<Book> companionBooks;
+
+    public Book() {
+
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public String getAuthor() {
+        return author;
+    }
+
+    public double getCost() {
+        return cost;
+    }
+
+    public void addCompanionBooks(Book book) {
+        if (companionBooks != null)
+            this.companionBooks.add(book);
+    }
+
+    public Book(String isbn, String title, String author, double cost, Publisher publisher) {
+        this.isbn = isbn;
+        this.title = title;
+        this.author = author;
+        this.cost = cost;
+        this.publisher = publisher;
+        this.companionBooks = new HashSet<>();
+    }
+
+    @Override
+    public String toString() {
+        return "Book [isbn=" + isbn + ", title=" + title + ", author=" + author + ", publisher=" + publisher + ", cost=" + cost + "]";
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + ((author == null) ? 0 : author.hashCode());
+        long temp;
+        temp = Double.doubleToLongBits(cost);
+        result = prime * result + (int) (temp ^ (temp >>> 32));
+        result = prime * result + ((isbn == null) ? 0 : isbn.hashCode());
+        result = prime * result + ((publisher == null) ? 0 : publisher.hashCode());
+        result = prime * result + ((title == null) ? 0 : title.hashCode());
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (getClass() != obj.getClass())
+            return false;
+        Book other = (Book) obj;
+        if (author == null) {
+            if (other.author != null)
+                return false;
+        } else if (!author.equals(other.author))
+            return false;
+        if (Double.doubleToLongBits(cost) != Double.doubleToLongBits(other.cost))
+            return false;
+        if (isbn == null) {
+            if (other.isbn != null)
+                return false;
+        } else if (!isbn.equals(other.isbn))
+            return false;
+        if (publisher == null) {
+            if (other.publisher != null)
+                return false;
+        } else if (!publisher.equals(other.publisher))
+            return false;
+        if (title == null) {
+            if (other.title != null)
+                return false;
+        } else if (!title.equals(other.title))
+            return false;
+        return true;
+    }
+
+}

persistence-modules/java-mongodb/src/main/java/com/baeldung/morphia/domain/Publisher.java

@@ -0,0 +1,70 @@
+package com.baeldung.morphia.domain;
+
+import org.bson.types.ObjectId;
+
+import dev.morphia.annotations.Entity;
+import dev.morphia.annotations.Id;
+
+@Entity
+public class Publisher {
+
+    @Id
+    private ObjectId id;
+    private String name;
+
+    public Publisher() {
+
+    }
+
+    public Publisher(ObjectId id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public ObjectId getId() {
+        return id;
+    }
+
+    public void setId(ObjectId id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    @Override
+    public String toString() {
+        return "Catalog [id=" + id + ", name=" + name + "]";
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + ((name == null) ? 0 : name.hashCode());
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (getClass() != obj.getClass())
+            return false;
+        Publisher other = (Publisher) obj;
+        if (name == null) {
+            if (other.name != null)
+                return false;
+        } else if (!name.equals(other.name))
+            return false;
+        return true;
+    }
+
+}

persistence-modules/java-mongodb/src/test/java/com/baeldung/morphia/MorphiaIntegrationTest.java

@@ -0,0 +1,131 @@
+package com.baeldung.morphia;
+
+import static dev.morphia.aggregation.Group.grouping;
+import static dev.morphia.aggregation.Group.push;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.util.Iterator;
+import java.util.List;
+
+import org.bson.types.ObjectId;
+import org.junit.BeforeClass;
+import org.junit.Ignore;
+import org.junit.Test;
+
+import com.baeldung.morphia.domain.Author;
+import com.baeldung.morphia.domain.Book;
+import com.baeldung.morphia.domain.Publisher;
+import com.mongodb.MongoClient;
+
+import dev.morphia.Datastore;
+import dev.morphia.Morphia;
+import dev.morphia.query.Query;
+import dev.morphia.query.UpdateOperations;
+
+@Ignore
+public class MorphiaIntegrationTest {
+
+    private static Datastore datastore;
+    private static ObjectId id = new ObjectId();
+
+    @BeforeClass
+    public static void setUp() {
+        Morphia morphia = new Morphia();
+        morphia.mapPackage("com.baeldung.morphia");
+        datastore = morphia.createDatastore(new MongoClient(), "library");
+        datastore.ensureIndexes();
+    }
+
+    @Test
+    public void givenDataSource_whenCreateEntity_thenEntityCreated() {
+        Publisher publisher = new Publisher(id, "Awsome Publisher");
+        Book book = new Book("9781565927186", "Learning Java", "Tom Kirkman", 3.95, publisher);
+        Book companionBook = new Book("9789332575103", "Java Performance Companion", "Tom Kirkman", 1.95, publisher);
+        book.addCompanionBooks(companionBook);
+        datastore.save(companionBook);
+        datastore.save(book);
+
+        List<Book> books = datastore.createQuery(Book.class)
+            .field("title")
+            .contains("Learning Java")
+            .find()
+            .toList();
+        assertEquals(1, books.size());
+        assertEquals(book, books.get(0));
+    }
+
+    @Test
+    public void givenDocument_whenUpdated_thenUpdateReflected() {
+        Publisher publisher = new Publisher(id, "Awsome Publisher");
+        Book book = new Book("9781565927186", "Learning Java", "Tom Kirkman", 3.95, publisher);
+        datastore.save(book);
+        Query<Book> query = datastore.createQuery(Book.class)
+            .field("title")
+            .contains("Learning Java");
+        UpdateOperations<Book> updates = datastore.createUpdateOperations(Book.class)
+            .inc("price", 1);
+        datastore.update(query, updates);
+        List<Book> books = datastore.createQuery(Book.class)
+            .field("title")
+            .contains("Learning Java")
+            .find()
+            .toList();
+        assertEquals(4.95, books.get(0)
+            .getCost());
+    }
+
+    @Test
+    public void givenDocument_whenDeleted_thenDeleteReflected() {
+        Publisher publisher = new Publisher(id, "Awsome Publisher");
+        Book book = new Book("9781565927186", "Learning Java", "Tom Kirkman", 3.95, publisher);
+        datastore.save(book);
+        Query<Book> query = datastore.createQuery(Book.class)
+            .field("title")
+            .contains("Learning Java");
+        datastore.delete(query);
+        List<Book> books = datastore.createQuery(Book.class)
+            .field("title")
+            .contains("Learning Java")
+            .find()
+            .toList();
+        assertEquals(0, books.size());
+    }
+
+    @Test
+    public void givenDocument_whenAggregated_thenResultsCollected() {
+        Publisher publisher = new Publisher(id, "Awsome Publisher");
+        datastore.save(new Book("9781565927186", "Learning Java", "Tom Kirkman", 3.95, publisher));
+        datastore.save(new Book("9781449313142", "Learning Perl", "Mark Pence", 2.95, publisher));
+        datastore.save(new Book("9787564100476", "Learning Python", "Mark Pence", 5.95, publisher));
+        datastore.save(new Book("9781449368814", "Learning Scala", "Mark Pence", 6.95, publisher));
+        datastore.save(new Book("9781784392338", "Learning Go", "Jonathan Sawyer", 8.95, publisher));
+
+        Iterator<Author> authors = datastore.createAggregation(Book.class)
+            .group("author", grouping("books", push("title")))
+            .out(Author.class);
+
+        assertTrue(authors.hasNext());
+
+    }
+
+    @Test
+    public void givenDocument_whenProjected_thenOnlyProjectionReceived() {
+        Publisher publisher = new Publisher(id, "Awsome Publisher");
+        Book book = new Book("9781565927186", "Learning Java", "Tom Kirkman", 3.95, publisher);
+        datastore.save(book);
+        List<Book> books = datastore.createQuery(Book.class)
+            .field("title")
+            .contains("Learning Java")
+            .project("title", true)
+            .find()
+            .toList();
+        assertEquals(books.size(), 1);
+        assertEquals("Learning Java", books.get(0)
+            .getTitle());
+        assertNull(books.get(0)
+            .getAuthor());
+    }
+
+}

persistence-modules/java-sql2o/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [A Guide to Sql2o](http://www.baeldung.com/sql2o)

persistence-modules/java-sql2o/pom.xml

@@ -0,0 +1,54 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>java-sql2o</artifactId>
+    <version>1.0-SNAPSHOT</version>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>8</source>
+                    <target>8</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+    <name>java-sql2o</name>
+
+    <parent>
+        <artifactId>persistence-modules</artifactId>
+        <groupId>com.baeldung</groupId>
+        <version>1.0.0-SNAPSHOT</version>
+        <relativePath>..</relativePath>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.sql2o</groupId>
+            <artifactId>sql2o</artifactId>
+            <version>${sql2o.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.hsqldb</groupId>
+            <artifactId>hsqldb</artifactId>
+            <version>${hsqldb.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>${junit.version}</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <hsqldb.version>2.4.0</hsqldb.version>
+        <junit.version>4.12</junit.version>
+        <sql2o.version>1.6.0</sql2o.version>
+    </properties>
+
+</project>

persistence-modules/java-sql2o/src/test/java/com/baeldung/persistence/sql2o/Sql2oIntegrationTest.java

@@ -0,0 +1,340 @@
+package com.baeldung.persistence.sql2o;
+
+import org.junit.Test;
+import org.sql2o.Connection;
+import org.sql2o.Query;
+import org.sql2o.ResultSetIterable;
+import org.sql2o.Sql2o;
+import org.sql2o.data.Row;
+import org.sql2o.data.Table;
+
+import java.sql.SQLException;
+import java.text.SimpleDateFormat;
+import java.util.*;
+
+import static org.junit.Assert.*;
+
+public class Sql2oIntegrationTest {
+
+    @Test
+    public void whenSql2oCreated_thenSuccess() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.open()) {
+            java.sql.Connection jdbcConnection = connection.getJdbcConnection();
+            assertFalse(jdbcConnection.isClosed());
+        } catch (SQLException e) {
+            fail(e.getMessage());
+        }
+    }
+
+    @Test
+    public void whenTableCreated_thenInsertIsPossible() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.open()) {
+            connection.createQuery("create table PROJECT_1 (id integer identity, name varchar(50), url varchar(100))").executeUpdate();
+            assertEquals(0, connection.getResult());
+            connection.createQuery("INSERT INTO PROJECT_1 VALUES (1, 'tutorials', 'github.com/eugenp/tutorials')").executeUpdate();
+            assertEquals(1, connection.getResult());
+            connection.createQuery("drop table PROJECT_1").executeUpdate();
+        }
+    }
+
+    @Test
+    public void whenIdentityColumn_thenInsertReturnsNewId() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.open()) {
+            connection.createQuery("create table PROJECT_2 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))").executeUpdate();
+            Query query = connection.createQuery(
+                    "INSERT INTO PROJECT_2 (NAME, URL) VALUES ('tutorials', 'github.com/eugenp/tutorials')",
+                    true);
+            assertEquals(0, query.executeUpdate().getKey());
+            query = connection.createQuery("INSERT INTO PROJECT_2 (NAME, URL) VALUES ('REST with Spring', 'github.com/eugenp/REST-With-Spring')",
+                    true);
+            assertEquals(1, query.executeUpdate().getKeys()[0]);
+            connection.createQuery("drop table PROJECT_2").executeUpdate();
+        }
+    }
+
+    @Test
+    public void whenSelect_thenResultsAreObjects() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.open()) {
+            connection.createQuery("create table PROJECT_3 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_3 (NAME, URL) VALUES ('tutorials', 'github.com/eugenp/tutorials')").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_3 (NAME, URL) VALUES ('REST with Spring', 'github.com/eugenp/REST-With-Spring')").executeUpdate();
+            Query query = connection.createQuery("select * from PROJECT_3 order by id");
+            List<Project> list = query.executeAndFetch(Project.class);
+
+            assertEquals("tutorials", list.get(0).getName());
+            assertEquals("REST with Spring", list.get(1).getName());
+
+            connection.createQuery("drop table PROJECT_3").executeUpdate();
+        }
+    }
+
+    @Test
+    public void whenSelectAlias_thenResultsAreObjects() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.open()) {
+            connection.createQuery("create table PROJECT_4 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100), creation_date date)").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_4 (NAME, URL, creation_date) VALUES ('tutorials', 'github.com/eugenp/tutorials', '2019-01-01')").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_4 (NAME, URL, creation_date) VALUES ('REST with Spring', 'github.com/eugenp/REST-With-Spring', '2019-02-01')").executeUpdate();
+            Query query = connection.createQuery("select NAME, URL, creation_date as creationDate from PROJECT_4 order by id");
+            List<Project> list = query.executeAndFetch(Project.class);
+            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
+            assertEquals("2019-01-01", sdf.format(list.get(0).getCreationDate()));
+            assertEquals("2019-02-01", sdf.format(list.get(1).getCreationDate()));
+
+            connection.createQuery("drop table PROJECT_4").executeUpdate();
+        }
+    }
+
+    @Test
+    public void whenSelectMapping_thenResultsAreObjects() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.open()) {
+            connection.createQuery("create table PROJECT_5 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100), creation_date date)").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_5 (NAME, URL, creation_date) VALUES ('tutorials', 'github.com/eugenp/tutorials', '2019-01-01')").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_5 (NAME, URL, creation_date) VALUES ('REST with Spring', 'github.com/eugenp/REST-With-Spring', '2019-02-01')").executeUpdate();
+            Query query = connection.createQuery("select * from PROJECT_5 order by id")
+                    .addColumnMapping("CrEaTiOn_date", "creationDate");
+            List<Project> list = query.executeAndFetch(Project.class);
+            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
+            assertEquals("2019-01-01", sdf.format(list.get(0).getCreationDate()));
+            assertEquals("2019-02-01", sdf.format(list.get(1).getCreationDate()));
+
+            connection.createQuery("drop table PROJECT_5").executeUpdate();
+        }
+    }
+
+    @Test
+    public void whenSelectCount_thenResultIsScalar() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.open()) {
+            connection.createQuery("create table PROJECT_6 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100), creation_date date)").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_6 (NAME, URL, creation_date) VALUES ('tutorials', 'github.com/eugenp/tutorials', '2019-01-01')").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_6 (NAME, URL, creation_date) VALUES ('REST with Spring', 'github.com/eugenp/REST-With-Spring', '2019-02-01')").executeUpdate();
+            Query query = connection.createQuery("select count(*) from PROJECT_6");
+            assertEquals(2.0, query.executeScalar(Double.TYPE), 0.001);
+            connection.createQuery("drop table PROJECT_6").executeUpdate();
+        }
+    }
+
+    @Test
+    public void whenFetchTable_thenResultsAreMaps() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.open()) {
+            connection.createQuery("create table PROJECT_5 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100), creation_date date)").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_5 (NAME, URL, creation_date) VALUES ('tutorials', 'github.com/eugenp/tutorials', '2019-01-01')").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_5 (NAME, URL, creation_date) VALUES ('REST with Spring', 'github.com/eugenp/REST-With-Spring', '2019-02-01')").executeUpdate();
+            Query query = connection.createQuery("select * from PROJECT_5 order by id");
+            Table table = query.executeAndFetchTable();
+            List<Map<String, Object>> list = table.asList();
+
+            assertEquals("tutorials", list.get(0).get("name"));
+            assertEquals("REST with Spring", list.get(1).get("name"));
+
+            connection.createQuery("drop table PROJECT_5").executeUpdate();
+        }
+    }
+
+    @Test
+    public void whenFetchTable_thenResultsAreRows() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.open()) {
+            connection.createQuery("create table PROJECT_5 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100), creation_date date)").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_5 (NAME, URL, creation_date) VALUES ('tutorials', 'github.com/eugenp/tutorials', '2019-01-01')").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_5 (NAME, URL, creation_date) VALUES ('REST with Spring', 'github.com/eugenp/REST-With-Spring', '2019-02-01')").executeUpdate();
+            Query query = connection.createQuery("select * from PROJECT_5 order by id");
+            Table table = query.executeAndFetchTable();
+            List<Row> rows = table.rows();
+
+            assertEquals("tutorials", rows.get(0).getString("name"));
+            assertEquals("REST with Spring", rows.get(1).getString("name"));
+
+            connection.createQuery("drop table PROJECT_5").executeUpdate();
+        }
+    }
+
+    @Test
+    public void whenParameters_thenReplacement() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.open()) {
+            connection.createQuery("create table PROJECT_10 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))").executeUpdate();
+            Query query = connection.createQuery("INSERT INTO PROJECT_10 (NAME, URL) VALUES (:name, :url)")
+                    .addParameter("name", "REST with Spring")
+                    .addParameter("url", "github.com/eugenp/REST-With-Spring");
+            assertEquals(1, query.executeUpdate().getResult());
+
+            List<Project> list = connection.createQuery("SELECT * FROM PROJECT_10 WHERE NAME = 'REST with Spring'").executeAndFetch(Project.class);
+            assertEquals(1, list.size());
+
+            connection.createQuery("drop table PROJECT_10").executeUpdate();
+        }
+    }
+
+    @Test
+    public void whenPOJOParameters_thenReplacement() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.open()) {
+            connection.createQuery("create table PROJECT_11 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))").executeUpdate();
+
+            Project project = new Project();
+            project.setName("REST with Spring");
+            project.setUrl("github.com/eugenp/REST-With-Spring");
+            connection.createQuery("INSERT INTO PROJECT_11 (NAME, URL) VALUES (:name, :url)")
+                    .bind(project).executeUpdate();
+            assertEquals(1, connection.getResult());
+
+            List<Project> list = connection.createQuery("SELECT * FROM PROJECT_11 WHERE NAME = 'REST with Spring'").executeAndFetch(Project.class);
+            assertEquals(1, list.size());
+
+            connection.createQuery("drop table PROJECT_11").executeUpdate();
+        }
+    }
+
+    @Test
+    public void whenTransactionRollback_thenNoDataInserted() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.beginTransaction()) {
+            connection.createQuery("create table PROJECT_12 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_12 (NAME, URL) VALUES ('tutorials', 'https://github.com/eugenp/tutorials')").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_12 (NAME, URL) VALUES ('REST with Spring', 'https://github.com/eugenp/REST-With-Spring')").executeUpdate();
+            connection.rollback();
+            List<Map<String, Object>> list = connection.createQuery("SELECT * FROM PROJECT_12").executeAndFetchTable().asList();
+            assertEquals(0, list.size());
+        }
+    }
+
+    @Test
+    public void whenTransactionEnds_thenSubsequentStatementsNotRolledBack() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.beginTransaction()) {
+            connection.createQuery("create table PROJECT_13 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_13 (NAME, URL) VALUES ('tutorials', 'https://github.com/eugenp/tutorials')").executeUpdate();
+            List<Map<String, Object>> list = connection.createQuery("SELECT * FROM PROJECT_13").executeAndFetchTable().asList();
+            assertEquals(1, list.size());
+            connection.rollback();
+            list = connection.createQuery("SELECT * FROM PROJECT_13").executeAndFetchTable().asList();
+            assertEquals(0, list.size());
+            connection.createQuery("INSERT INTO PROJECT_13 (NAME, URL) VALUES ('REST with Spring', 'https://github.com/eugenp/REST-With-Spring')").executeUpdate();
+            list = connection.createQuery("SELECT * FROM PROJECT_13").executeAndFetchTable().asList();
+            assertEquals(1, list.size());
+            //No implicit rollback
+        }
+        try(Connection connection = sql2o.beginTransaction()) {
+            List<Map<String, Object>> list = connection.createQuery("SELECT * FROM PROJECT_13").executeAndFetchTable().asList();
+            assertEquals(1, list.size());
+        }
+    }
+
+    @Test
+    public void whenTransactionRollbackThenCommit_thenOnlyLastInserted() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.beginTransaction()) {
+            connection.createQuery("create table PROJECT_14 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_14 (NAME, URL) VALUES ('tutorials', 'https://github.com/eugenp/tutorials')").executeUpdate();
+            List<Map<String, Object>> list = connection.createQuery("SELECT * FROM PROJECT_14").executeAndFetchTable().asList();
+            assertEquals(1, list.size());
+            connection.rollback(false);
+            list = connection.createQuery("SELECT * FROM PROJECT_14").executeAndFetchTable().asList();
+            assertEquals(0, list.size());
+            connection.createQuery("INSERT INTO PROJECT_14 (NAME, URL) VALUES ('REST with Spring', 'https://github.com/eugenp/REST-With-Spring')").executeUpdate();
+            list = connection.createQuery("SELECT * FROM PROJECT_14").executeAndFetchTable().asList();
+            assertEquals(1, list.size());
+            //Implicit rollback
+        }
+        try(Connection connection = sql2o.beginTransaction()) {
+            List<Map<String, Object>> list = connection.createQuery("SELECT * FROM PROJECT_14").executeAndFetchTable().asList();
+            assertEquals(0, list.size());
+            connection.createQuery("INSERT INTO PROJECT_14 (NAME, URL) VALUES ('tutorials', 'https://github.com/eugenp/tutorials')").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_14 (NAME, URL) VALUES ('REST with Spring', 'https://github.com/eugenp/REST-With-Spring')").executeUpdate();
+            connection.commit();
+            list = connection.createQuery("SELECT * FROM PROJECT_14").executeAndFetchTable().asList();
+            assertEquals(2, list.size());
+        }
+        try(Connection connection = sql2o.beginTransaction()) {
+            List<Map<String, Object>> list = connection.createQuery("SELECT * FROM PROJECT_14").executeAndFetchTable().asList();
+            assertEquals(2, list.size());
+        }
+    }
+
+    @Test
+    public void whenBatch_thenMultipleInserts() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.beginTransaction()) {
+            connection.createQuery("create table PROJECT_15 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))").executeUpdate();
+            Query query = connection.createQuery("INSERT INTO PROJECT_15 (NAME, URL) VALUES (:name, :url)");
+            for(int i = 0; i < 1000; i++) {
+                query.addParameter("name", "tutorials" + i);
+                query.addParameter("url", "https://github.com/eugenp/tutorials" + i);
+                query.addToBatch();
+            }
+            query.executeBatch();
+            connection.commit();
+        }
+        try(Connection connection = sql2o.beginTransaction()) {
+            assertEquals(1000L, connection.createQuery("SELECT count(*) FROM PROJECT_15").executeScalar());
+        }
+    }
+
+    @Test
+    public void whenLazyFetch_thenResultsAreObjects() {
+        Sql2o sql2o = new Sql2o("jdbc:hsqldb:mem:testDB", "sa", "");
+        try(Connection connection = sql2o.open()) {
+            connection.createQuery("create table PROJECT_16 (ID IDENTITY, NAME VARCHAR (50), URL VARCHAR (100))").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_16 (NAME, URL) VALUES ('tutorials', 'github.com/eugenp/tutorials')").executeUpdate();
+            connection.createQuery("INSERT INTO PROJECT_16 (NAME, URL) VALUES ('REST with Spring', 'github.com/eugenp/REST-With-Spring')").executeUpdate();
+            Query query = connection.createQuery("select * from PROJECT_16 order by id");
+            try(ResultSetIterable<Project> projects = query.executeAndFetchLazy(Project.class)) {
+                for(Project p : projects) {
+                    assertNotNull(p.getName());
+                    assertNotNull(p.getUrl());
+                    assertNull(p.getCreationDate());
+                }
+            }
+            connection.createQuery("drop table PROJECT_16").executeUpdate();
+        }
+    }
+
+    static class Project {
+        private long id;
+        private String name;
+        private String url;
+        private Date creationDate;
+
+        public long getId() {
+            return id;
+        }
+
+        public void setId(long id) {
+            this.id = id;
+        }
+
+        public String getName() {
+            return name;
+        }
+
+        public void setName(String name) {
+            this.name = name;
+        }
+
+        public String getUrl() {
+            return url;
+        }
+
+        public void setUrl(String url) {
+            this.url = url;
+        }
+
+        public Date getCreationDate() {
+            return creationDate;
+        }
+
+        public void setCreationDate(Date creationDate) {
+            this.creationDate = creationDate;
+        }
+    }
+
+
+}

persistence-modules/jpa-hibernate-cascade-type/README.md

@@ -0,0 +1,3 @@
+## Relevant articles:
+
+- [Overview of JPA/Hibernate Cascade Types](https://www.baeldung.com/jpa-cascade-types)

persistence-modules/jpa-hibernate-cascade-type/pom.xml

@@ -0,0 +1,71 @@
+<?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">
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>parent-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+        <relativePath>../../</relativePath>
+    </parent>
+
+    <artifactId>jpa-hibernate-cascade-type</artifactId>
+    <modelVersion>4.0.0</modelVersion>
+    <version>1.0.0-SNAPSHOT</version>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.hibernate</groupId>
+            <artifactId>hibernate-core</artifactId>
+            <version>${hibernate.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj-core.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>com.h2database</groupId>
+            <artifactId>h2</artifactId>
+            <version>${h2.version}</version>
+        </dependency>
+        <!-- validation -->
+        <dependency>
+            <groupId>org.hibernate</groupId>
+            <artifactId>hibernate-validator</artifactId>
+            <version>${hibernate-validator.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>javax.el</groupId>
+            <artifactId>javax.el-api</artifactId>
+            <version>${javax.el-api.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.glassfish</groupId>
+            <artifactId>javax.el</artifactId>
+            <version>${org.glassfish.javax.el.version}</version>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <finalName>jpa-hibernate-cascade-type</finalName>
+        <resources>
+            <resource>
+                <directory>src/test/resources</directory>
+                <filtering>true</filtering>
+            </resource>
+        </resources>
+    </build>
+
+    <properties>
+        <hibernate.version>5.4.3.Final</hibernate.version>
+        <assertj-core.version>3.12.2</assertj-core.version>
+        <hibernate-validator.version>6.0.17.Final</hibernate-validator.version>
+        <javax.el-api.version>3.0.0</javax.el-api.version>
+        <org.glassfish.javax.el.version>3.0.1-b11</org.glassfish.javax.el.version>
+        <maven.compiler.source>1.8</maven.compiler.source>
+        <maven.compiler.target>1.8</maven.compiler.target>
+    </properties>
+
+</project>

persistence-modules/jpa-hibernate-cascade-type/src/main/java/com/baeldung/cascading/HibernateUtil.java

@@ -0,0 +1,45 @@
+package com.baeldung.cascading;
+
+import com.baeldung.cascading.domain.Address;
+import com.baeldung.cascading.domain.Person;
+import org.hibernate.SessionFactory;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.hibernate.cfg.Configuration;
+import org.hibernate.service.ServiceRegistry;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.net.URL;
+import java.util.Properties;
+
+public class HibernateUtil {
+    private static SessionFactory sessionFactory;
+
+    public static SessionFactory getSessionFactory() {
+        try {
+            Properties properties = getProperties();
+            Configuration configuration = new Configuration();
+            configuration.setProperties(properties);
+            configuration.addAnnotatedClass(Person.class);
+            configuration.addAnnotatedClass(Address.class);
+            ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()
+                    .applySettings(configuration.getProperties()).build();
+            sessionFactory = configuration.buildSessionFactory(serviceRegistry);
+            return sessionFactory;
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        return sessionFactory;
+    }
+
+    private static Properties getProperties() throws IOException {
+        Properties properties = new Properties();
+        URL propertiesURL = Thread.currentThread()
+                .getContextClassLoader()
+                .getResource("hibernate.properties");
+        try (FileInputStream inputStream = new FileInputStream(propertiesURL.getFile())) {
+            properties.load(inputStream);
+        }
+        return properties;
+    }
+}

persistence-modules/jpa-hibernate-cascade-type/src/main/java/com/baeldung/cascading/domain/Address.java

@@ -0,0 +1,64 @@
+package com.baeldung.cascading.domain;
+
+import javax.persistence.*;
+
+@Entity
+public class Address {
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private int id;
+    private String street;
+    private int houseNumber;
+    private String city;
+    private int zipCode;
+    @ManyToOne(fetch = FetchType.LAZY)
+    private Person person;
+
+    public int getId() {
+        return id;
+    }
+
+    public void setId(int id) {
+        this.id = id;
+    }
+
+    public Person getPerson() {
+        return person;
+    }
+
+    public void setPerson(Person person) {
+        this.person = person;
+    }
+
+    public String getStreet() {
+        return street;
+    }
+
+    public int getHouseNumber() {
+        return houseNumber;
+    }
+
+    public void setHouseNumber(int houseNumber) {
+        this.houseNumber = houseNumber;
+    }
+
+    public String getCity() {
+        return city;
+    }
+
+    public void setCity(String city) {
+        this.city = city;
+    }
+
+    public int getZipCode() {
+        return zipCode;
+    }
+
+    public void setZipCode(int zipCode) {
+        this.zipCode = zipCode;
+    }
+
+    public void setStreet(String street) {
+        this.street = street;
+    }
+}

persistence-modules/jpa-hibernate-cascade-type/src/main/java/com/baeldung/cascading/domain/Person.java

@@ -0,0 +1,38 @@
+package com.baeldung.cascading.domain;
+
+import javax.persistence.*;
+import java.util.List;
+
+@Entity
+public class Person {
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private int id;
+    private String name;
+    @OneToMany(mappedBy = "person", cascade = CascadeType.ALL)
+    private List<Address> addresses;
+
+    public int getId() {
+        return id;
+    }
+
+    public void setId(int id) {
+        this.id = id;
+    }
+
+    public List<Address> getAddresses() {
+        return addresses;
+    }
+
+    public void setAddresses(List<Address> addresses) {
+        this.addresses = addresses;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+}

persistence-modules/jpa-hibernate-cascade-type/src/test/java/com/baeldung/cascading/CasCadeTypeUnitTest.java

@@ -0,0 +1,169 @@
+package com.baeldung.cascading;
+
+import com.baeldung.cascading.domain.Address;
+import com.baeldung.cascading.domain.Person;
+import org.assertj.core.api.Assertions;
+import org.hibernate.*;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import java.util.Arrays;
+
+public class CasCadeTypeUnitTest {
+    private static SessionFactory sessionFactory;
+    private Session session;
+    private Transaction transaction;
+
+    @BeforeClass
+    public static void beforeTests() {
+        sessionFactory = HibernateUtil.getSessionFactory();
+    }
+
+    @Before
+    public void setUp() {
+        session = sessionFactory.openSession();
+        transaction = session.beginTransaction();
+    }
+
+    @After
+    public void tearDown() {
+        transaction.rollback();
+        session.close();
+    }
+
+    @Test
+    public void testPersist() {
+        Person person = new Person();
+        Address address = new Address();
+        address.setPerson(person);
+        person.setAddresses(Arrays.asList(address));
+        session.persist(person);
+        session.flush();
+        session.clear();
+    }
+
+    @Test
+    public void testMerge() {
+        int addressId;
+        Person person = buildPerson("devender");
+        Address address = buildAddress(person);
+        person.setAddresses(Arrays.asList(address));
+        session.persist(person);
+        session.flush();
+        addressId = address.getId();
+        session.clear();
+
+        Address savedAddressEntity = session.find(Address.class, addressId);
+        Person savedPersonEntity = savedAddressEntity.getPerson();
+        savedPersonEntity.setName("devender kumar");
+        savedAddressEntity.setHouseNumber(24);
+        session.merge(savedPersonEntity);
+        session.flush();
+    }
+
+    @Test
+    public void testRemove() {
+        int personId;
+        Person person = buildPerson("devender");
+        Address address = buildAddress(person);
+        person.setAddresses(Arrays.asList(address));
+        session.persist(person);
+        session.flush();
+        personId = person.getId();
+        session.clear();
+
+        Person savedPersonEntity = session.find(Person.class, personId);
+        session.remove(savedPersonEntity);
+        session.flush();
+    }
+
+    @Test
+    public void testDetach() {
+        Person person = buildPerson("devender");
+        Address address = buildAddress(person);
+        person.setAddresses(Arrays.asList(address));
+        session.persist(person);
+        session.flush();
+        Assertions.assertThat(session.contains(person)).isTrue();
+        Assertions.assertThat(session.contains(address)).isTrue();
+
+        session.detach(person);
+        Assertions.assertThat(session.contains(person)).isFalse();
+        Assertions.assertThat(session.contains(address)).isFalse();
+    }
+
+    @Test
+    public void testLock() {
+        Person person = buildPerson("devender");
+        Address address = buildAddress(person);
+        person.setAddresses(Arrays.asList(address));
+        session.persist(person);
+        session.flush();
+        Assertions.assertThat(session.contains(person)).isTrue();
+        Assertions.assertThat(session.contains(address)).isTrue();
+
+        session.detach(person);
+        Assertions.assertThat(session.contains(person)).isFalse();
+        Assertions.assertThat(session.contains(address)).isFalse();
+        session.unwrap(Session.class)
+                .buildLockRequest(new LockOptions(LockMode.NONE))
+                .lock(person);
+
+        Assertions.assertThat(session.contains(person)).isTrue();
+        Assertions.assertThat(session.contains(address)).isTrue();
+    }
+
+    @Test
+    public void testRefresh() {
+        Person person = buildPerson("devender");
+        Address address = buildAddress(person);
+        person.setAddresses(Arrays.asList(address));
+        session.persist(person);
+        session.flush();
+        person.setName("Devender Kumar");
+        address.setHouseNumber(24);
+        session.refresh(person);
+        Assertions.assertThat(person.getName()).isEqualTo("devender");
+        Assertions.assertThat(address.getHouseNumber()).isEqualTo(23);
+    }
+
+    @Test
+    public void testReplicate() {
+        Person person = buildPerson("devender");
+        person.setId(2);
+        Address address = buildAddress(person);
+        address.setId(2);
+        person.setAddresses(Arrays.asList(address));
+        session.unwrap(Session.class).replicate(person, ReplicationMode.OVERWRITE);
+        session.flush();
+        Assertions.assertThat(person.getId()).isEqualTo(2);
+        Assertions.assertThat(address.getId()).isEqualTo(2);
+    }
+
+    @Test
+    public void testSaveOrUpdate() {
+        Person person = buildPerson("devender");
+        Address address = buildAddress(person);
+        person.setAddresses(Arrays.asList(address));
+        session.saveOrUpdate(person);
+        session.flush();
+    }
+
+    private Address buildAddress(Person person) {
+        Address address = new Address();
+        address.setCity("Berlin");
+        address.setHouseNumber(23);
+        address.setStreet("Zeughofstraße");
+        address.setZipCode(123001);
+        address.setPerson(person);
+        return address;
+    }
+
+    private Person buildPerson(String name) {
+        Person person = new Person();
+        person.setName(name);
+        return person;
+    }
+}

persistence-modules/jpa-hibernate-cascade-type/src/test/resources/hibernate.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.connection.autocommit=true
+jdbc.password=
+
+hibernate.dialect=org.hibernate.dialect.H2Dialect
+hibernate.show_sql=true
+hibernate.hbm2ddl.auto=create-drop
+

persistence-modules/pom.xml

@@ -18,6 +18,7 @@
         <module>apache-cayenne</module>
         <module>core-java-persistence</module>
         <module>deltaspike</module>
+        <module>elasticsearch</module>
         <module>flyway</module>
         <module>hbase</module>
         <module>hibernate5</module>
@@ -28,7 +29,9 @@
         <module>java-cockroachdb</module>
         <module>java-jdbi</module>
         <module>java-jpa</module>
+        <module>java-jpa-2</module>
         <module>java-mongodb</module>
+        <module>java-sql2o</module>
         <module>jnosql</module>
         <module>liquibase</module>
         <module>orientdb</module>
@@ -56,5 +59,7 @@
         <module>spring-hibernate4</module>
         <module>spring-jpa</module>
         <module>spring-persistence-simple</module>
+        <module>jpa-hibernate-cascade-type</module>
+				<module>r2dbc</module>
     </modules>
 </project>

persistence-modules/r2dbc/.gitignore

@@ -0,0 +1,31 @@
+HELP.md
+target/
+!.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**
+!**/src/test/**
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+
+### VS Code ###
+.vscode/

persistence-modules/r2dbc/.mvn/wrapper/MavenWrapperDownloader.java

@@ -0,0 +1,114 @@
+/*
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  https://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied.  See the License for the
+specific language governing permissions and limitations
+under the License.
+*/
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.net.URL;
+import java.nio.channels.Channels;
+import java.nio.channels.ReadableByteChannel;
+import java.util.Properties;
+
+public class MavenWrapperDownloader {
+
+    /**
+     * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided.
+     */
+    private static final String DEFAULT_DOWNLOAD_URL =
+            "https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar";
+
+    /**
+     * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to
+     * use instead of the default one.
+     */
+    private static final String MAVEN_WRAPPER_PROPERTIES_PATH =
+            ".mvn/wrapper/maven-wrapper.properties";
+
+    /**
+     * Path where the maven-wrapper.jar will be saved to.
+     */
+    private static final String MAVEN_WRAPPER_JAR_PATH =
+            ".mvn/wrapper/maven-wrapper.jar";
+
+    /**
+     * Name of the property which should be used to override the default download url for the wrapper.
+     */
+    private static final String PROPERTY_NAME_WRAPPER_URL = "wrapperUrl";
+
+    public static void main(String args[]) {
+        System.out.println("- Downloader started");
+        File baseDirectory = new File(args[0]);
+        System.out.println("- Using base directory: " + baseDirectory.getAbsolutePath());
+
+        // If the maven-wrapper.properties exists, read it and check if it contains a custom
+        // wrapperUrl parameter.
+        File mavenWrapperPropertyFile = new File(baseDirectory, MAVEN_WRAPPER_PROPERTIES_PATH);
+        String url = DEFAULT_DOWNLOAD_URL;
+        if(mavenWrapperPropertyFile.exists()) {
+            FileInputStream mavenWrapperPropertyFileInputStream = null;
+            try {
+                mavenWrapperPropertyFileInputStream = new FileInputStream(mavenWrapperPropertyFile);
+                Properties mavenWrapperProperties = new Properties();
+                mavenWrapperProperties.load(mavenWrapperPropertyFileInputStream);
+                url = mavenWrapperProperties.getProperty(PROPERTY_NAME_WRAPPER_URL, url);
+            } catch (IOException e) {
+                System.out.println("- ERROR loading '" + MAVEN_WRAPPER_PROPERTIES_PATH + "'");
+            } finally {
+                try {
+                    if(mavenWrapperPropertyFileInputStream != null) {
+                        mavenWrapperPropertyFileInputStream.close();
+                    }
+                } catch (IOException e) {
+                    // Ignore ...
+                }
+            }
+        }
+        System.out.println("- Downloading from: : " + url);
+
+        File outputFile = new File(baseDirectory.getAbsolutePath(), MAVEN_WRAPPER_JAR_PATH);
+        if(!outputFile.getParentFile().exists()) {
+            if(!outputFile.getParentFile().mkdirs()) {
+                System.out.println(
+                        "- ERROR creating output direcrory '" + outputFile.getParentFile().getAbsolutePath() + "'");
+            }
+        }
+        System.out.println("- Downloading to: " + outputFile.getAbsolutePath());
+        try {
+            downloadFileFromURL(url, outputFile);
+            System.out.println("Done");
+            System.exit(0);
+        } catch (Throwable e) {
+            System.out.println("- Error downloading");
+            e.printStackTrace();
+            System.exit(1);
+        }
+    }
+
+    private static void downloadFileFromURL(String urlString, File destination) throws Exception {
+        URL website = new URL(urlString);
+        ReadableByteChannel rbc;
+        rbc = Channels.newChannel(website.openStream());
+        FileOutputStream fos = new FileOutputStream(destination);
+        fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+        fos.close();
+        rbc.close();
+    }
+
+}

persistence-modules/r2dbc/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.6.0/apache-maven-3.6.0-bin.zip

persistence-modules/r2dbc/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles:
+- [R2DBC – Reactive Relational Database Connectivity](https://www.baeldung.com/r2dbc)
+

persistence-modules/r2dbc/mvnw

@@ -0,0 +1,286 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven2 Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ] ; then
+
+  if [ -f /etc/mavenrc ] ; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ] ; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+    # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+    # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+    if [ -z "$JAVA_HOME" ]; then
+      if [ -x "/usr/libexec/java_home" ]; then
+        export JAVA_HOME="`/usr/libexec/java_home`"
+      else
+        export JAVA_HOME="/Library/Java/Home"
+      fi
+    fi
+    ;;
+esac
+
+if [ -z "$JAVA_HOME" ] ; then
+  if [ -r /etc/gentoo-release ] ; then
+    JAVA_HOME=`java-config --jre-home`
+  fi
+fi
+
+if [ -z "$M2_HOME" ] ; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+      PRG="$link"
+    else
+      PRG="`dirname "$PRG"`/$link"
+    fi
+  done
+
+  saveddir=`pwd`
+
+  M2_HOME=`dirname "$PRG"`/..
+
+  # make it fully qualified
+  M2_HOME=`cd "$M2_HOME" && pwd`
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --unix "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="`(cd "$M2_HOME"; pwd)`"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
+  # TODO classpath?
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="`which javac`"
+  if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=`which readlink`
+    if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
+      if $darwin ; then
+        javaHome="`dirname \"$javaExecutable\"`"
+        javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
+      else
+        javaExecutable="`readlink -f \"$javaExecutable\"`"
+      fi
+      javaHome="`dirname \"$javaExecutable\"`"
+      javaHome=`expr "$javaHome" : '\(.*\)/bin'`
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ] ; then
+  if [ -n "$JAVA_HOME"  ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="`which java`"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ] ; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ] ; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]
+  then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=`cd "$wdir/.."; pwd`
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+BASE_DIR=`find_maven_basedir "$(pwd)"`
+if [ -z "$BASE_DIR" ]; then
+  exit 1;
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found .mvn/wrapper/maven-wrapper.jar"
+    fi
+else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+    fi
+    jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar"
+    while IFS="=" read key value; do
+      case "$key" in (wrapperUrl) jarUrl="$value"; break ;;
+      esac
+    done < "$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Downloading from: $jarUrl"
+    fi
+    wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+
+    if command -v wget > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found wget ... using wget"
+        fi
+        wget "$jarUrl" -O "$wrapperJarPath"
+    elif command -v curl > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found curl ... using curl"
+        fi
+        curl -o "$wrapperJarPath" "$jarUrl"
+    else
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Falling back to using Java to download"
+        fi
+        javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+        if [ -e "$javaClass" ]; then
+            if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Compiling MavenWrapperDownloader.java ..."
+                fi
+                # Compiling the Java class
+                ("$JAVA_HOME/bin/javac" "$javaClass")
+            fi
+            if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                # Running the downloader
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Running MavenWrapperDownloader.java ..."
+                fi
+                ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+            fi
+        fi
+    fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --path --windows "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"`
+fi
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

persistence-modules/r2dbc/mvnw.cmd

@@ -0,0 +1,161 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    https://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven2 Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a key stroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing my setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.4.2/maven-wrapper-0.4.2.jar"
+FOR /F "tokens=1,2 delims==" %%A IN (%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties) DO (
+	IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B 
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    echo Found %WRAPPER_JAR%
+) else (
+    echo Couldn't find %WRAPPER_JAR%, downloading it ...
+	echo Downloading from: %DOWNLOAD_URL%
+    powershell -Command "(New-Object Net.WebClient).DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"
+    echo Finished downloading %WRAPPER_JAR%
+)
+@REM End of extension
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%

persistence-modules/r2dbc/pom.xml

@@ -0,0 +1,90 @@
+<?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>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.1.6.RELEASE</version>
+		<relativePath /> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>org.baeldung.examples.r2dbc</groupId>
+	<artifactId>r2dbc-example</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>r2dbc-example</name>
+	<description>Sample R2DBC Project</description>
+
+	<properties>
+		<java.version>1.8</java.version>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-webflux</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>io.projectreactor</groupId>
+			<artifactId>reactor-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+
+
+		<!-- R2DBC H2 Driver -->
+		<dependency>
+			<groupId>io.r2dbc</groupId>
+			<artifactId>r2dbc-h2</artifactId>
+			<version>0.8.0.M8</version>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-configuration-processor</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-devtools</artifactId>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+	<!-- Extra repositories for R2DBC-H2 -->
+	<repositories>
+
+		<repository>
+			<id>spring-snapshots</id>
+			<name>Spring Snapshots</name>
+			<url>https://repo.spring.io/snapshot</url>
+			<snapshots>
+				<enabled>true</enabled>
+			</snapshots>
+		</repository>
+
+		<repository>
+			<id>spring-milestones</id>
+			<name>Spring Milestones</name>
+			<url>https://repo.spring.io/milestone</url>
+			<snapshots>
+				<enabled>false</enabled>
+			</snapshots>
+		</repository>
+
+	</repositories>
+
+</project>

persistence-modules/r2dbc/src/main/java/org/baeldung/examples/r2dbc/Account.java

@@ -0,0 +1,68 @@
+package org.baeldung.examples.r2dbc;
+
+import java.math.BigDecimal;
+
+public class Account {
+
+    private Long id;
+    private String iban;
+    private BigDecimal balance;
+    
+    
+    public Account() {}
+    
+    public Account(Long id, String iban, BigDecimal balance) {
+        this.id = id;
+        this.iban = iban;
+        this.balance = balance;
+    }
+
+    public Account(Long id, String iban, Double balance) {
+        this.id = id;
+        this.iban = iban;
+        this.balance = new BigDecimal(balance);
+    }
+    
+    /**
+     * @return the id
+     */
+    public Long getId() {
+        return id;
+    }
+
+    /**
+     * @param id the id to set
+     */
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    /**
+     * @return the iban
+     */
+    public String getIban() {
+        return iban;
+    }
+
+    /**
+     * @param iban the iban to set
+     */
+    public void setIban(String iban) {
+        this.iban = iban;
+    }
+
+    /**
+     * @return the balance
+     */
+    public BigDecimal getBalance() {
+        return balance;
+    }
+
+    /**
+     * @param balance the balance to set
+     */
+    public void setBalance(BigDecimal balance) {
+        this.balance = balance;
+    }
+
+}

persistence-modules/r2dbc/src/main/java/org/baeldung/examples/r2dbc/AccountResource.java

@@ -0,0 +1,56 @@
+/**
+ * 
+ */
+package org.baeldung.examples.r2dbc;
+
+import java.math.BigDecimal;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RestController;
+
+import io.r2dbc.spi.Connection;
+import io.r2dbc.spi.ConnectionFactory;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+/**
+ * @author Philippe
+ *
+ */
+@RestController
+public class AccountResource {
+
+    private final ReactiveAccountDao accountDao;
+
+    public AccountResource(ReactiveAccountDao accountDao) {
+        this.accountDao = accountDao;
+    }
+
+    @GetMapping("/accounts/{id}")
+    public Mono<ResponseEntity<Account>> getAccount(@PathVariable("id") Long id) {
+
+        return accountDao.findById(id)
+          .map(acc -> new ResponseEntity<>(acc, HttpStatus.OK))
+          .switchIfEmpty(Mono.just(new ResponseEntity<>(null, HttpStatus.NOT_FOUND)));
+    }
+
+    @GetMapping("/accounts")
+    public Flux<Account> getAllAccounts() {
+        return accountDao.findAll();
+    }
+
+    @PostMapping("/accounts")
+    public Mono<ResponseEntity<Account>> postAccount(@RequestBody Account account) {
+        return accountDao.createAccount(account)
+          .map(acc -> new ResponseEntity<>(acc, HttpStatus.CREATED))
+          .log();
+    }
+
+}

persistence-modules/r2dbc/src/main/java/org/baeldung/examples/r2dbc/DatasourceConfig.java

@@ -0,0 +1,65 @@
+package org.baeldung.examples.r2dbc;
+
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.util.StringUtils;
+
+import io.netty.util.internal.StringUtil;
+import io.r2dbc.spi.ConnectionFactories;
+import io.r2dbc.spi.ConnectionFactory;
+import io.r2dbc.spi.ConnectionFactoryOptions;
+import io.r2dbc.spi.ConnectionFactoryOptions.Builder;
+import io.r2dbc.spi.Option;
+import reactor.core.publisher.Flux;
+
+import static io.r2dbc.spi.ConnectionFactoryOptions.*;
+
+
+@Configuration
+public class DatasourceConfig {
+    
+    @Bean
+    public ConnectionFactory connectionFactory(R2DBCConfigurationProperties properties) {
+        
+        ConnectionFactoryOptions baseOptions = ConnectionFactoryOptions.parse(properties.getUrl());
+        Builder ob = ConnectionFactoryOptions.builder().from(baseOptions);
+        if ( !StringUtil.isNullOrEmpty(properties.getUser())) {
+            ob = ob.option(USER, properties.getUser());
+        }
+
+        if ( !StringUtil.isNullOrEmpty(properties.getPassword())) {
+            ob = ob.option(PASSWORD, properties.getPassword());
+        }
+        
+        ConnectionFactory cf = ConnectionFactories.get(ob.build());
+        return cf;
+    }
+    
+
+    @Bean
+    public CommandLineRunner initDatabase(ConnectionFactory cf) {
+    
+        return (args) ->
+          Flux.from(cf.create())
+              .flatMap(c -> 
+                Flux.from(c.createBatch()
+                  .add("drop table if exists Account")
+                  .add("create table Account(" +
+                    "id IDENTITY(1,1)," +
+                    "iban varchar(80) not null," +
+                    "balance DECIMAL(18,2) not null)")
+                  .add("insert into Account(iban,balance)" +
+                    "values('BR430120980198201982',100.00)")
+                  .add("insert into Account(iban,balance)" +
+                    "values('BR430120998729871000',250.00)")
+                  .execute())
+                .doFinally((st) -> c.close())
+              )
+              .log()
+              .blockLast();
+    }
+
+
+}
+

persistence-modules/r2dbc/src/main/java/org/baeldung/examples/r2dbc/R2DBCConfigurationProperties.java

@@ -0,0 +1,58 @@
+package org.baeldung.examples.r2dbc;
+
+import javax.validation.constraints.NotEmpty;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+
+@ConfigurationProperties(prefix = "r2dbc")
+public class R2DBCConfigurationProperties {
+
+    @NotEmpty
+    private String url;
+
+    private String user;
+    private String password;
+
+    /**
+     * @return the url
+     */
+    public String getUrl() {
+        return url;
+    }
+
+    /**
+     * @param url the url to set
+     */
+    public void setUrl(String url) {
+        this.url = url;
+    }
+
+    /**
+     * @return the user
+     */
+    public String getUser() {
+        return user;
+    }
+
+    /**
+     * @param user the user to set
+     */
+    public void setUser(String user) {
+        this.user = user;
+    }
+
+    /**
+     * @return the password
+     */
+    public String getPassword() {
+        return password;
+    }
+
+    /**
+     * @param password the password to set
+     */
+    public void setPassword(String password) {
+        this.password = password;
+    }
+
+}

persistence-modules/r2dbc/src/main/java/org/baeldung/examples/r2dbc/R2dbcExampleApplication.java

@@ -0,0 +1,17 @@
+package org.baeldung.examples.r2dbc;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+
+@SpringBootApplication
+@EnableConfigurationProperties(R2DBCConfigurationProperties.class)
+public class R2dbcExampleApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(R2dbcExampleApplication.class, args);
+    }
+    
+    
+
+}

persistence-modules/r2dbc/src/main/java/org/baeldung/examples/r2dbc/ReactiveAccountDao.java

@@ -0,0 +1,76 @@
+package org.baeldung.examples.r2dbc;
+
+import java.math.BigDecimal;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Component;
+
+import io.r2dbc.spi.Connection;
+import io.r2dbc.spi.ConnectionFactory;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+@Component
+public class ReactiveAccountDao {
+
+    private ConnectionFactory connectionFactory;
+
+    public ReactiveAccountDao(ConnectionFactory connectionFactory) {
+        this.connectionFactory = connectionFactory;
+    }
+
+    public Mono<Account> findById(long id) {
+
+        return Mono.from(connectionFactory.create())
+          .flatMap(c -> Mono.from(c.createStatement("select id,iban,balance from Account where id = $1")
+            .bind("$1", id)
+            .execute())
+             .doFinally((st) -> close(c)))
+          .map(result -> result.map((row, meta) -> 
+            new Account(row.get("id", Long.class),
+              row.get("iban", String.class),
+              row.get("balance", BigDecimal.class))))
+          .flatMap( p -> Mono.from(p));
+    }
+
+    public Flux<Account> findAll() {
+
+        return Mono.from(connectionFactory.create())
+            .flatMap((c) -> Mono.from(c.createStatement("select id,iban,balance from Account")
+                .execute())
+                .doFinally((st) -> close(c)))
+            .flatMapMany(result -> Flux.from(result.map((row, meta) -> {
+                Account acc = new Account();
+                acc.setId(row.get("id", Long.class));
+                acc.setIban(row.get("iban", String.class));
+                acc.setBalance(row.get("balance", BigDecimal.class));
+                return acc;
+            })));
+    }
+    
+    public Mono<Account> createAccount(Account account) {
+        
+        return Mono.from(connectionFactory.create())
+          .flatMap(c -> Mono.from(c.beginTransaction())
+            .then(Mono.from(c.createStatement("insert into Account(iban,balance) values($1,$2)")
+              .bind("$1", account.getIban())
+              .bind("$2", account.getBalance())
+              .returnGeneratedValues("id")
+              .execute()))
+            .map(result -> result.map((row, meta) -> 
+                new Account(row.get("id", Long.class),
+                  account.getIban(),
+                  account.getBalance())))
+            .flatMap(pub -> Mono.from(pub))
+            .delayUntil(r -> c.commitTransaction())
+            .doFinally((st) -> c.close()));
+        
+    }
+
+    private <T> Mono<T> close(Connection connection) {
+        return Mono.from(connection.close())
+          .then(Mono.empty());
+    }
+
+}

persistence-modules/r2dbc/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -0,0 +1,5 @@
+{"properties": [{
+  "name": "r2dbc",
+  "type": "org.baeldung.examples.r2dbc.R2DBCConfigurationProperties",
+  "description": "R2DBC Connection properties"
+}]}

persistence-modules/r2dbc/src/main/resources/application.yml

@@ -0,0 +1,13 @@
+spring:
+  application:
+    name: r2dbc-test
+    
+# R2DBC URL
+r2dbc:
+  url: r2dbc:h2:mem://./testdb
+  
+  
+  
+    
+    
+    

persistence-modules/r2dbc/src/test/java/org/baeldung/examples/r2dbc/R2dbcExampleApplicationTests.java

@@ -0,0 +1,102 @@
+package org.baeldung.examples.r2dbc;
+
+import static org.hamcrest.CoreMatchers.*;
+import static org.junit.Assert.*;
+
+import java.util.List;
+
+import org.hamcrest.core.IsNull;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.MediaType;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.web.reactive.server.WebTestClient;
+
+import io.r2dbc.spi.ConnectionFactory;
+import reactor.core.publisher.Flux;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
+public class R2dbcExampleApplicationTests {
+    
+    
+    @Autowired
+    private WebTestClient webTestClient;
+    
+    @Autowired
+    ConnectionFactory cf;
+    
+    @Before
+    public void initDatabase() {
+        
+        Flux.from(cf.create())
+          .flatMap(c -> 
+            c.createBatch()
+              .add("drop table if exists Account")
+              .add("create table Account(id IDENTITY(1,1), iban varchar(80) not null, balance DECIMAL(18,2) not null)")
+              .add("insert into Account(iban,balance) values ( 'BR430120980198201982', 100.00 ) ")
+              .add("insert into Account(iban,balance) values ( 'BR430120998729871000', 250.00 ) ")
+              .execute()
+          )
+          .log()
+          .blockLast();
+    }
+
+    @Test
+    public void givenExistingAccountId_whenGetAccount_thenReturnExistingAccountInfo() {
+        
+        webTestClient
+          .get()
+          .uri("/accounts/1")
+          .accept(MediaType.APPLICATION_JSON)
+          .exchange()
+          .expectStatus()
+            .isOk()
+          .expectBody(Account.class)
+            .value((acc) -> {
+                assertThat(acc.getId(),is(1l));
+            });
+    }
+    
+    @Test
+    public void givenDatabaseHasSomeAccounts_whenGetAccount_thenReturnExistingAccounts() {
+        
+        webTestClient
+          .get()
+          .uri("/accounts")
+          .accept(MediaType.APPLICATION_JSON)
+          .exchange()
+          .expectStatus()
+            .isOk()
+          .expectBody(List.class)
+            .value((accounts) -> {
+                assertThat(accounts.size(),not(is(0)));
+            });
+    }
+    
+    
+    @Test
+    public void givenNewAccountData_whenPostAccount_thenReturnNewAccountInfo() {
+
+        webTestClient
+        .post()
+        .uri("/accounts")
+        .syncBody(new Account(null,"BR4303010298012098", 151.00 ))
+        .accept(MediaType.APPLICATION_JSON)
+        .exchange()
+        .expectStatus()
+          .is2xxSuccessful()
+        .expectBody(Account.class)
+          .value((acc) -> {
+              assertThat(acc.getId(),is(notNullValue()));
+          });
+        
+    }
+
+}

persistence-modules/r2dbc/src/test/resources/application.yml

@@ -0,0 +1,6 @@
+# R2DBC Test configuration
+r2dbc:
+  url: r2dbc:h2:mem://./testdb
+  
+  
+  

persistence-modules/spring-boot-mysql/.gitignore

@@ -0,0 +1,5 @@
+/target/
+.settings/
+.classpath
+.project
+.mvn/

persistence-modules/spring-boot-mysql/pom.xml

@@ -0,0 +1,59 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+    <modelVersion>4.0.0</modelVersion>
+    <artifactId>spring-boot-mysql</artifactId>
+    <version>0.1.0</version>
+    <name>spring-boot-mysql</name>
+
+    <parent>
+        <artifactId>parent-boot-2</artifactId>
+        <groupId>com.baeldung</groupId>
+        <version>0.0.1-SNAPSHOT</version>
+        <relativePath>../../parent-boot-2</relativePath>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+            <version>2.1.5.RELEASE</version>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-data-jpa</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-devtools</artifactId>
+            <optional>true</optional>
+        </dependency>
+        <dependency>
+            <groupId>mysql</groupId>
+            <artifactId>mysql-connector-java</artifactId>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <finalName>spring-boot-mysql-timezone</finalName>
+        <resources>
+            <resource>
+                <directory>src/main/resources</directory>
+                <filtering>true</filtering>
+            </resource>
+        </resources>
+        <plugins>
+
+        </plugins>
+    </build>
+
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <mysql-connector-java.version>8.0.12</mysql-connector-java.version>
+    </properties>
+
+</project>

persistence-modules/spring-boot-mysql/src/main/java/com/baeldung/boot/Application.java

@@ -0,0 +1,20 @@
+package com.baeldung.boot;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+import javax.annotation.PostConstruct;
+import java.util.TimeZone;
+
+@SpringBootApplication
+public class Application {
+
+    @PostConstruct
+    void started() {
+        TimeZone.setDefault(TimeZone.getTimeZone("UTC"));
+    }
+
+    public static void main(String[] args) {
+        SpringApplication.run(Application.class, args);
+    }
+}

persistence-modules/spring-boot-mysql/src/main/java/com/baeldung/boot/Controller.java

@@ -0,0 +1,27 @@
+package com.baeldung.boot;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.List;
+
+@RestController
+public class Controller {
+
+    @Autowired
+    UserRepository userRepository;
+
+    @GetMapping
+    public User get() {
+        User user = new User();
+        userRepository.save(user);
+        return user;
+    }
+
+    @GetMapping("/find")
+    public List<User> find() {
+        List<User> users = userRepository.findAll();
+        return users;
+    }
+}

persistence-modules/spring-boot-mysql/src/main/java/com/baeldung/boot/User.java

@@ -0,0 +1,40 @@
+package com.baeldung.boot;
+
+
+import org.springframework.data.annotation.CreatedDate;
+
+import javax.persistence.*;
+import java.util.Date;
+
+@Entity
+public class User {
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private Integer id;
+
+    @Column
+    private String name;
+
+    @CreatedDate
+    private Date createdDate = new Date();
+
+    public Date getCreatedDate() {
+        return createdDate;
+    }
+
+    public Integer getId() {
+        return id;
+    }
+
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+}

persistence-modules/spring-boot-mysql/src/main/java/com/baeldung/boot/UserRepository.java

@@ -0,0 +1,10 @@
+package com.baeldung.boot;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+import java.io.Serializable;
+
+@Repository
+public interface UserRepository extends JpaRepository<User, Serializable> {
+}

persistence-modules/spring-boot-mysql/src/main/resources/application.yml

@@ -0,0 +1,14 @@
+spring:
+  datasource:
+    url: jdbc:mysql://localhost:3306/test?useLegacyDatetimeCode=false
+    username: root
+    password:
+
+  jpa:
+    hibernate:
+      ddl-auto: update
+    properties:
+      hibernate:
+        dialect: org.hibernate.dialect.MySQL5Dialect
+        jdbc:
+          time_zone: UTC

persistence-modules/spring-boot-persistence-h2/src/test/java/com/baeldung/SpringContextTest.java

@@ -0,0 +1,19 @@
+package com.baeldung;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.support.AnnotationConfigContextLoader;
+import org.springframework.test.context.web.WebAppConfiguration;
+
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(loader = AnnotationConfigContextLoader.class)
+@WebAppConfiguration
+public class SpringContextTest {
+
+    @Test
+    public void whenSpringContextIsBootstrapped_thenNoExceptions() {
+    }
+}

persistence-modules/spring-boot-persistence-mongodb/README.md

@@ -2,3 +2,4 @@
 
 - [Auto-Generated Field for MongoDB using Spring Boot](https://www.baeldung.com/spring-boot-mongodb-auto-generated-field)
 - [Spring Boot Integration Testing with Embedded MongoDB](http://www.baeldung.com/spring-boot-embedded-mongodb)
+- [Upload and Retrieve Files Using MongoDB and Spring Boot](https://www.baeldung.com/spring-boot-mongodb-upload-file)

persistence-modules/spring-boot-persistence-mongodb/pom.xml

@@ -20,6 +20,10 @@
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-web</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-thymeleaf</artifactId>
+        </dependency>        
         <!-- MongoDB -->
         <dependency>
             <groupId>org.springframework.boot</groupId>

persistence-modules/spring-boot-persistence-mongodb/src/main/java/com/baeldung/mongodb/daos/PhotoRepository.java

@@ -0,0 +1,9 @@
+package com.baeldung.mongodb.daos;
+
+import org.springframework.data.mongodb.repository.MongoRepository;
+
+import com.baeldung.mongodb.models.Photo;
+
+public interface PhotoRepository extends MongoRepository<Photo, String> {
+
+}

persistence-modules/spring-boot-persistence-mongodb/src/main/java/com/baeldung/mongodb/models/Photo.java

@@ -0,0 +1,51 @@
+package com.baeldung.mongodb.models;
+
+import org.bson.types.Binary;
+import org.springframework.data.annotation.Id;
+import org.springframework.data.mongodb.core.mapping.Document;
+
+@Document(collection = "photos")
+public class Photo {
+    
+    @Id
+    private String id;
+    
+    private String title;
+        
+    private Binary image;
+
+    public Photo(String title) {
+        super();
+        this.title = title;
+    }
+
+    public String getId() {
+        return id;
+    }
+
+    public void setId(String id) {
+        this.id = id;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public Binary getImage() {
+        return image;
+    }
+
+    public void setImage(Binary image) {
+        this.image = image;
+    }
+
+    @Override
+    public String toString() {
+        return "Photo [id=" + id + ", title=" + title + ", image=" + image + "]";
+    }
+    
+}

persistence-modules/spring-boot-persistence-mongodb/src/main/java/com/baeldung/mongodb/models/Video.java

@@ -0,0 +1,39 @@
+package com.baeldung.mongodb.models;
+
+import java.io.InputStream;
+
+public class Video {
+    private String title;
+    private InputStream stream;
+    
+    public Video() {
+        super();
+    }
+
+    public Video(String title) {
+        super();
+        this.title = title;
+    }
+
+    public String getTitle() {
+        return title;
+    }
+
+    public void setTitle(String title) {
+        this.title = title;
+    }
+
+    public InputStream getStream() {
+        return stream;
+    }
+
+    public void setStream(InputStream stream) {
+        this.stream = stream;
+    }
+
+    @Override
+    public String toString() {
+        return "Video [title=" + title + "]";
+    }
+
+}

persistence-modules/spring-boot-persistence-mongodb/src/main/java/com/baeldung/mongodb/services/PhotoService.java

@@ -0,0 +1,30 @@
+package com.baeldung.mongodb.services;
+
+import java.io.IOException;
+
+import org.bson.BsonBinarySubType;
+import org.bson.types.Binary;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+import org.springframework.web.multipart.MultipartFile;
+
+import com.baeldung.mongodb.daos.PhotoRepository;
+import com.baeldung.mongodb.models.Photo;
+
+@Service
+public class PhotoService {
+
+    @Autowired
+    private PhotoRepository photoRepo;
+
+    public Photo getPhoto(String id) {
+        return photoRepo.findById(id).get();
+    }
+
+    public String addPhoto(String title, MultipartFile file) throws IOException {
+        Photo photo = new Photo(title);
+        photo.setImage(new Binary(BsonBinarySubType.BINARY, file.getBytes()));
+        photo = photoRepo.insert(photo);
+        return photo.getId();
+    }
+}

persistence-modules/spring-boot-persistence-mongodb/src/main/java/com/baeldung/mongodb/services/VideoService.java

@@ -0,0 +1,44 @@
+package com.baeldung.mongodb.services;
+
+import java.io.IOException;
+
+import org.bson.types.ObjectId;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.data.mongodb.core.query.Criteria;
+import org.springframework.data.mongodb.core.query.Query;
+import org.springframework.data.mongodb.gridfs.GridFsOperations;
+import org.springframework.data.mongodb.gridfs.GridFsTemplate;
+import org.springframework.stereotype.Service;
+import org.springframework.web.multipart.MultipartFile;
+
+import com.baeldung.mongodb.models.Video;
+import com.mongodb.BasicDBObject;
+import com.mongodb.DBObject;
+import com.mongodb.client.gridfs.model.GridFSFile;
+
+@Service
+public class VideoService {
+
+    @Autowired
+    private GridFsTemplate gridFsTemplate;
+
+    @Autowired
+    private GridFsOperations operations;
+
+    public Video getVideo(String id) throws IllegalStateException, IOException {
+        GridFSFile file = gridFsTemplate.findOne(new Query(Criteria.where("_id").is(id)));
+        Video video = new Video();
+        video.setTitle(file.getMetadata().get("title").toString());
+        video.setStream(operations.getResource(file).getInputStream());
+        return video;
+    }
+
+    public String addVideo(String title, MultipartFile file) throws IOException {
+        DBObject metaData = new BasicDBObject();
+        metaData.put("type", "video");
+        metaData.put("title", title);
+        ObjectId id = gridFsTemplate.store(file.getInputStream(), file.getName(), file.getContentType(), metaData);
+        return id.toString();
+    }
+
+}

persistence-modules/spring-boot-persistence-mongodb/src/main/java/com/baeldung/mongodb/web/PhotoController.java

@@ -0,0 +1,43 @@
+package com.baeldung.mongodb.web;
+
+import java.io.IOException;
+import java.util.Base64;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.multipart.MultipartFile;
+
+import com.baeldung.mongodb.models.Photo;
+import com.baeldung.mongodb.services.PhotoService;
+
+@Controller
+public class PhotoController {
+
+    @Autowired
+    private PhotoService photoService;
+
+    @GetMapping("/photos/{id}")
+    public String getPhoto(@PathVariable String id, Model model) {
+        Photo photo = photoService.getPhoto(id);
+        model.addAttribute("title", photo.getTitle());
+        model.addAttribute("image", Base64.getEncoder().encodeToString(photo.getImage().getData()));
+        return "photos";
+    }
+
+    @GetMapping("/photos/upload")
+    public String uploadPhoto(Model model) {
+        model.addAttribute("message", "hello");
+        return "uploadPhoto";
+    }
+
+    @PostMapping("/photos/add")
+    public String addPhoto(@RequestParam("title") String title, @RequestParam("image") MultipartFile image, Model model) throws IOException {
+        String id = photoService.addPhoto(title, image);
+        return "redirect:/photos/" + id;
+    }
+}

persistence-modules/spring-boot-persistence-mongodb/src/main/java/com/baeldung/mongodb/web/VideoController.java

@@ -0,0 +1,51 @@
+package com.baeldung.mongodb.web;
+
+import java.io.IOException;
+
+import javax.servlet.http.HttpServletResponse;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.util.FileCopyUtils;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.multipart.MultipartFile;
+
+import com.baeldung.mongodb.models.Video;
+import com.baeldung.mongodb.services.VideoService;
+
+@Controller
+public class VideoController {
+
+    @Autowired
+    private VideoService videoService;
+
+    @GetMapping("/videos/{id}")
+    public String getVideo(@PathVariable String id, Model model) throws IllegalStateException, IOException {
+        Video video = videoService.getVideo(id);
+        model.addAttribute("title", video.getTitle());
+        model.addAttribute("url", "/videos/stream/" + id);
+        return "videos";
+    }
+
+    @GetMapping("/videos/stream/{id}")
+    public void streamVideo(@PathVariable String id, HttpServletResponse response) throws IllegalStateException, IOException {
+        Video video = videoService.getVideo(id);
+        FileCopyUtils.copy(video.getStream(), response.getOutputStream());
+    }
+
+    @GetMapping("/videos/upload")
+    public String uploadVideo(Model model) {
+        model.addAttribute("message", "hello");
+        return "uploadVideo";
+    }
+
+    @PostMapping("/videos/add")
+    public String addVideo(@RequestParam("title") String title, @RequestParam("file") MultipartFile file, Model model) throws IOException {
+        String id = videoService.addVideo(title, file);
+        return "redirect:/videos/" + id;
+    }
+}

persistence-modules/spring-boot-persistence-mongodb/src/main/resources/application.properties

@@ -1,8 +1,13 @@
 spring.application.name=spring-boot-persistence
-server.port=${PORT:0}
+server.port=8082
 
 #spring boot mongodb
 spring.data.mongodb.host=localhost
 spring.data.mongodb.port=27017
 spring.data.mongodb.database=springboot-mongo
 
+spring.thymeleaf.cache=false
+
+spring.servlet.multipart.max-file-size=256MB
+spring.servlet.multipart.max-request-size=256MB
+spring.servlet.multipart.enabled=true

persistence-modules/spring-boot-persistence-mongodb/src/main/resources/templates/index.html

@@ -0,0 +1,14 @@
+<html xmlns:th="https://www.thymeleaf.org">
+<head>
+<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
+<title>Upload Files MongoDB</title>
+</head>
+<body>
+	<h1>Home Page</h1>
+	<div th:if="${message != null}" th:text="${message}">Message</div>
+	<br/>
+	<a href="/photos/upload">Upload new Photo</a>
+	<br/><br/>
+	<a href="/videos/upload">Upload new Video</a>	
+</body>
+</html>

persistence-modules/spring-boot-persistence-mongodb/src/main/resources/templates/photos.html

@@ -0,0 +1,10 @@
+<html xmlns:th="https://www.thymeleaf.org">
+<body>
+	<h1>View Photo</h1>
+	Title: <span th:text="${title}">name</span>
+	<br/>
+	<img alt="sample" th:src="*{'data:image/png;base64,'+image}" width="200"/>
+	<br/> <br/>
+	<a href="/">Back to home page</a>	
+</body>
+</html>

persistence-modules/spring-boot-persistence-mongodb/src/main/resources/templates/uploadPhoto.html

@@ -0,0 +1,15 @@
+<html xmlns:th="https://www.thymeleaf.org">
+<body>
+
+<h1>Upload new Photo</h1>
+<form method="POST" action="/photos/add" enctype="multipart/form-data">
+	Title:<input type="text" name="title" />
+	<br/>
+	Image:<input type="file" name="image" accept="image/*" />
+	<br/>
+	<br/>
+    <input type="submit" value="Upload" />
+</form>
+
+</body>
+</html>

persistence-modules/spring-boot-persistence-mongodb/src/main/resources/templates/uploadVideo.html

@@ -0,0 +1,15 @@
+<html xmlns:th="https://www.thymeleaf.org">
+<body>
+
+<h1>Upload new Video</h1>
+<form method="POST" action="/videos/add" enctype="multipart/form-data">
+	Title:<input type="text" name="title" />
+	<br/>
+	Video:<input type="file" name="file" accept="video/*" />
+	<br/>
+	<br/>
+    <input type="submit" value="Upload" />
+</form>
+
+</body>
+</html>

persistence-modules/spring-boot-persistence-mongodb/src/main/resources/templates/videos.html

@@ -0,0 +1,15 @@
+<html xmlns:th="https://www.thymeleaf.org">
+<body>
+	<h1>View Video</h1>
+	Title: <span th:text="${title}">title</span>
+	<br/>
+	<br/>
+	
+	<video width="400" controls>
+    	<source th:src="${url}" />
+  	</video>
+  	
+  	<br/> <br/>
+	<a href="/">Back to home page</a>
+</body>
+</html>

persistence-modules/spring-data-cassandra-reactive/pom.xml

@@ -46,6 +46,13 @@
             <artifactId>reactor-test</artifactId>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.cassandraunit</groupId>
+            <artifactId>cassandra-unit-spring</artifactId>
+            <version>${cassandra-unit-spring.version}</version>
+            <scope>test</scope>
+        </dependency>
+        
     </dependencies>
 
     <properties>
@@ -53,6 +60,7 @@
         <project.reporting.outputEncoding>UTF-8
         </project.reporting.outputEncoding>
         <spring-data-cassandra.version>2.1.2.RELEASE</spring-data-cassandra.version>
+        <cassandra-unit-spring.version>3.11.2.0</cassandra-unit-spring.version>
     </properties>
 
 </project>

persistence-modules/spring-data-cassandra-reactive/src/test/java/com/baeldung/cassandra/reactive/ReactiveEmployeeRepositoryIntegrationTest.java

@@ -1,13 +1,23 @@
 package com.baeldung.cassandra.reactive;
 
-import com.baeldung.cassandra.reactive.model.Employee;
-import com.baeldung.cassandra.reactive.repository.EmployeeRepository;
+import org.cassandraunit.spring.CassandraDataSet;
+import org.cassandraunit.spring.CassandraUnitDependencyInjectionTestExecutionListener;
+import org.cassandraunit.spring.CassandraUnitTestExecutionListener;
+import org.cassandraunit.spring.EmbeddedCassandra;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.TestExecutionListeners;
 import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.test.context.support.DependencyInjectionTestExecutionListener;
+import org.springframework.test.context.support.DirtiesContextTestExecutionListener;
+import org.springframework.test.context.web.ServletTestExecutionListener;
+
+import com.baeldung.cassandra.reactive.model.Employee;
+import com.baeldung.cassandra.reactive.repository.EmployeeRepository;
+
 import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 import reactor.test.StepVerifier;
@@ -15,6 +25,15 @@ import reactor.test.StepVerifier;
 
 @RunWith(SpringRunner.class)
 @SpringBootTest
+@TestExecutionListeners(listeners = {
+        CassandraUnitDependencyInjectionTestExecutionListener.class,
+        CassandraUnitTestExecutionListener.class,
+        ServletTestExecutionListener.class,
+        DependencyInjectionTestExecutionListener.class,
+        DirtiesContextTestExecutionListener.class
+})
+@EmbeddedCassandra(timeout = 60000, configuration = "cassandra-server.yaml")
+@CassandraDataSet(value = {"cassandra-init.cql"}, keyspace = "practice")
 public class ReactiveEmployeeRepositoryIntegrationTest {
 
 	@Autowired

persistence-modules/spring-data-cassandra-reactive/src/test/resources/cassandra-init.cql

@@ -0,0 +1,7 @@
+CREATE TABLE employee(
+    id int PRIMARY KEY,
+    name text,
+    address text,
+    email text,
+    age int
+);

persistence-modules/spring-data-cassandra-reactive/src/test/resources/cassandra-server.yaml

@@ -0,0 +1,590 @@
+# Cassandra storage config YAML
+
+# NOTE:
+#   See http://wiki.apache.org/cassandra/StorageConfiguration for
+#   full explanations of configuration directives
+# /NOTE
+
+# The name of the cluster. This is mainly used to prevent machines in
+# one logical cluster from joining another.
+cluster_name: 'Test Cluster'
+
+# You should always specify InitialToken when setting up a production
+# cluster for the first time, and often when adding capacity later.
+# The principle is that each node should be given an equal slice of
+# the token ring; see http://wiki.apache.org/cassandra/Operations
+# for more details.
+#
+# If blank, Cassandra will request a token bisecting the range of
+# the heaviest-loaded existing node.  If there is no load information
+# available, such as is the case with a new cluster, it will pick
+# a random token, which will lead to hot spots.
+#initial_token:
+
+# See http://wiki.apache.org/cassandra/HintedHandoff
+hinted_handoff_enabled: true
+# this defines the maximum amount of time a dead host will have hints
+# generated.  After it has been dead this long, new hints for it will not be
+# created until it has been seen alive and gone down again.
+max_hint_window_in_ms: 10800000 # 3 hours
+# Maximum throttle in KBs per second, per delivery thread.  This will be
+# reduced proportionally to the number of nodes in the cluster.  (If there
+# are two nodes in the cluster, each delivery thread will use the maximum
+# rate; if there are three, each will throttle to half of the maximum,
+# since we expect two nodes to be delivering hints simultaneously.)
+hinted_handoff_throttle_in_kb: 1024
+# Number of threads with which to deliver hints;
+# Consider increasing this number when you have multi-dc deployments, since
+# cross-dc handoff tends to be slower
+max_hints_delivery_threads: 2
+
+hints_directory: target/embeddedCassandra/hints
+
+# The following setting populates the page cache on memtable flush and compaction
+# WARNING: Enable this setting only when the whole node's data fits in memory.
+# Defaults to: false
+# populate_io_cache_on_flush: false
+
+# Authentication backend, implementing IAuthenticator; used to identify users
+# Out of the box, Cassandra provides org.apache.cassandra.auth.{AllowAllAuthenticator,
+# PasswordAuthenticator}.
+#
+# - AllowAllAuthenticator performs no checks - set it to disable authentication.
+# - PasswordAuthenticator relies on username/password pairs to authenticate
+#   users. It keeps usernames and hashed passwords in system_auth.credentials table.
+#   Please increase system_auth keyspace replication factor if you use this authenticator.
+authenticator: AllowAllAuthenticator
+
+# Authorization backend, implementing IAuthorizer; used to limit access/provide permissions
+# Out of the box, Cassandra provides org.apache.cassandra.auth.{AllowAllAuthorizer,
+# CassandraAuthorizer}.
+#
+# - AllowAllAuthorizer allows any action to any user - set it to disable authorization.
+# - CassandraAuthorizer stores permissions in system_auth.permissions table. Please
+#   increase system_auth keyspace replication factor if you use this authorizer.
+authorizer: AllowAllAuthorizer
+
+# Validity period for permissions cache (fetching permissions can be an
+# expensive operation depending on the authorizer, CassandraAuthorizer is
+# one example). Defaults to 2000, set to 0 to disable.
+# Will be disabled automatically for AllowAllAuthorizer.
+permissions_validity_in_ms: 2000
+
+
+# The partitioner is responsible for distributing rows (by key) across
+# nodes in the cluster.  Any IPartitioner may be used, including your/m
+# own as long as it is on the classpath.  Out of the box, Cassandra
+# provides org.apache.cassandra.dht.{Murmur3Partitioner, RandomPartitioner
+# ByteOrderedPartitioner, OrderPreservingPartitioner (deprecated)}.
+#
+# - RandomPartitioner distributes rows across the cluster evenly by md5.
+#   This is the default prior to 1.2 and is retained for compatibility.
+# - Murmur3Partitioner is similar to RandomPartioner but uses Murmur3_128
+#   Hash Function instead of md5.  When in doubt, this is the best option.
+# - ByteOrderedPartitioner orders rows lexically by key bytes.  BOP allows
+#   scanning rows in key order, but the ordering can generate hot spots
+#   for sequential insertion workloads.
+# - OrderPreservingPartitioner is an obsolete form of BOP, that stores
+# - keys in a less-efficient format and only works with keys that are
+#   UTF8-encoded Strings.
+# - CollatingOPP collates according to EN,US rules rather than lexical byte
+#   ordering.  Use this as an example if you need custom collation.
+#
+# See http://wiki.apache.org/cassandra/Operations for more on
+# partitioners and token selection.
+partitioner: org.apache.cassandra.dht.Murmur3Partitioner
+
+# directories where Cassandra should store data on disk.
+data_file_directories:
+    - target/embeddedCassandra/data
+
+# commit log
+commitlog_directory: target/embeddedCassandra/commitlog
+
+cdc_raw_directory: target/embeddedCassandra/cdc
+
+# policy for data disk failures:
+# stop: shut down gossip and Thrift, leaving the node effectively dead, but
+#       can still be inspected via JMX.
+# best_effort: stop using the failed disk and respond to requests based on
+#              remaining available sstables.  This means you WILL see obsolete
+#              data at CL.ONE!
+# ignore: ignore fatal errors and let requests fail, as in pre-1.2 Cassandra
+disk_failure_policy: stop
+
+
+# Maximum size of the key cache in memory.
+#
+# Each key cache hit saves 1 seek and each row cache hit saves 2 seeks at the
+# minimum, sometimes more. The key cache is fairly tiny for the amount of
+# time it saves, so it's worthwhile to use it at large numbers.
+# The row cache saves even more time, but must store the whole values of
+# its rows, so it is extremely space-intensive. It's best to only use the
+# row cache if you have hot rows or static rows.
+#
+# NOTE: if you reduce the size, you may not get you hottest keys loaded on startup.
+#
+# Default value is empty to make it "auto" (min(5% of Heap (in MB), 100MB)). Set to 0 to disable key cache.
+key_cache_size_in_mb:
+
+# Duration in seconds after which Cassandra should
+# safe the keys cache. Caches are saved to saved_caches_directory as
+# specified in this configuration file.
+#
+# Saved caches greatly improve cold-start speeds, and is relatively cheap in
+# terms of I/O for the key cache. Row cache saving is much more expensive and
+# has limited use.
+#
+# Default is 14400 or 4 hours.
+key_cache_save_period: 14400
+
+# Number of keys from the key cache to save
+# Disabled by default, meaning all keys are going to be saved
+# key_cache_keys_to_save: 100
+
+# Maximum size of the row cache in memory.
+# NOTE: if you reduce the size, you may not get you hottest keys loaded on startup.
+#
+# Default value is 0, to disable row caching.
+row_cache_size_in_mb: 0
+
+# Duration in seconds after which Cassandra should
+# safe the row cache. Caches are saved to saved_caches_directory as specified
+# in this configuration file.
+#
+# Saved caches greatly improve cold-start speeds, and is relatively cheap in
+# terms of I/O for the key cache. Row cache saving is much more expensive and
+# has limited use.
+#
+# Default is 0 to disable saving the row cache.
+row_cache_save_period: 0
+
+# Number of keys from the row cache to save
+# Disabled by default, meaning all keys are going to be saved
+# row_cache_keys_to_save: 100
+
+# saved caches
+saved_caches_directory: target/embeddedCassandra/saved_caches
+
+# commitlog_sync may be either "periodic" or "batch."
+# When in batch mode, Cassandra won't ack writes until the commit log
+# has been fsynced to disk.  It will wait up to
+# commitlog_sync_batch_window_in_ms milliseconds for other writes, before
+# performing the sync.
+#
+# commitlog_sync: batch
+# commitlog_sync_batch_window_in_ms: 50
+#
+# the other option is "periodic" where writes may be acked immediately
+# and the CommitLog is simply synced every commitlog_sync_period_in_ms
+# milliseconds.
+commitlog_sync: periodic
+commitlog_sync_period_in_ms: 10000
+
+# The size of the individual commitlog file segments.  A commitlog
+# segment may be archived, deleted, or recycled once all the data
+# in it (potentially from each columnfamily in the system) has been
+# flushed to sstables.
+#
+# The default size is 32, which is almost always fine, but if you are
+# archiving commitlog segments (see commitlog_archiving.properties),
+# then you probably want a finer granularity of archiving; 8 or 16 MB
+# is reasonable.
+commitlog_segment_size_in_mb: 32
+
+# any class that implements the SeedProvider interface and has a
+# constructor that takes a Map<String, String> of parameters will do.
+seed_provider:
+    # Addresses of hosts that are deemed contact points.
+    # Cassandra nodes use this list of hosts to find each other and learn
+    # the topology of the ring.  You must change this if you are running
+    # multiple nodes!
+    - class_name: org.apache.cassandra.locator.SimpleSeedProvider
+      parameters:
+          # seeds is actually a comma-delimited list of addresses.
+          # Ex: "<ip1>,<ip2>,<ip3>"
+          - seeds: "127.0.0.1"
+
+
+# For workloads with more data than can fit in memory, Cassandra's
+# bottleneck will be reads that need to fetch data from
+# disk. "concurrent_reads" should be set to (16 * number_of_drives) in
+# order to allow the operations to enqueue low enough in the stack
+# that the OS and drives can reorder them.
+#
+# On the other hand, since writes are almost never IO bound, the ideal
+# number of "concurrent_writes" is dependent on the number of cores in
+# your system; (8 * number_of_cores) is a good rule of thumb.
+concurrent_reads: 32
+concurrent_writes: 32
+
+# Total memory to use for memtables.  Cassandra will flush the largest
+# memtable when this much memory is used.
+# If omitted, Cassandra will set it to 1/3 of the heap.
+# memtable_total_space_in_mb: 2048
+
+# Total space to use for commitlogs.
+# If space gets above this value (it will round up to the next nearest
+# segment multiple), Cassandra will flush every dirty CF in the oldest
+# segment and remove it.
+# commitlog_total_space_in_mb: 4096
+
+# This sets the amount of memtable flush writer threads.  These will
+# be blocked by disk io, and each one will hold a memtable in memory
+# while blocked. If you have a large heap and many data directories,
+# you can increase this value for better flush performance.
+# By default this will be set to the amount of data directories defined.
+#memtable_flush_writers: 1
+
+# the number of full memtables to allow pending flush, that is,
+# waiting for a writer thread.  At a minimum, this should be set to
+# the maximum number of secondary indexes created on a single CF.
+#memtable_flush_queue_size: 4
+
+# Whether to, when doing sequential writing, fsync() at intervals in
+# order to force the operating system to flush the dirty
+# buffers. Enable this to avoid sudden dirty buffer flushing from
+# impacting read latencies. Almost always a good idea on SSD:s; not
+# necessarily on platters.
+trickle_fsync: false
+trickle_fsync_interval_in_kb: 10240
+
+# TCP port, for commands and data
+storage_port: 7010
+
+# SSL port, for encrypted communication.  Unused unless enabled in
+# encryption_options
+ssl_storage_port: 7011
+
+# Address to bind to and tell other Cassandra nodes to connect to. You
+# _must_ change this if you want multiple nodes to be able to
+# communicate!
+#
+# Leaving it blank leaves it up to InetAddress.getLocalHost(). This
+# will always do the Right Thing *if* the node is properly configured
+# (hostname, name resolution, etc), and the Right Thing is to use the
+# address associated with the hostname (it might not be).
+#
+# Setting this to 0.0.0.0 is always wrong.
+listen_address: 127.0.0.1
+
+start_native_transport: true
+# port for the CQL native transport to listen for clients on
+native_transport_port: 9042
+
+# Whether to start the thrift rpc server.
+start_rpc: true
+
+# Address to broadcast to other Cassandra nodes
+# Leaving this blank will set it to the same value as listen_address
+# broadcast_address: 1.2.3.4
+
+# The address to bind the Thrift RPC service to -- clients connect
+# here. Unlike ListenAddress above, you *can* specify 0.0.0.0 here if
+# you want Thrift to listen on all interfaces.
+#
+# Leaving this blank has the same effect it does for ListenAddress,
+# (i.e. it will be based on the configured hostname of the node).
+rpc_address: localhost
+# port for Thrift to listen for clients on
+rpc_port: 9171
+
+# enable or disable keepalive on rpc connections
+rpc_keepalive: true
+
+# Cassandra provides three options for the RPC Server:
+#
+# sync  -> One connection per thread in the rpc pool (see below).
+#          For a very large number of clients, memory will be your limiting
+#          factor; on a 64 bit JVM, 128KB is the minimum stack size per thread.
+#          Connection pooling is very, very strongly recommended.
+#
+# async -> Nonblocking server implementation with one thread to serve
+#          rpc connections.  This is not recommended for high throughput use
+#          cases. Async has been tested to be about 50% slower than sync
+#          or hsha and is deprecated: it will be removed in the next major release.
+#
+# hsha  -> Stands for "half synchronous, half asynchronous." The rpc thread pool
+#          (see below) is used to manage requests, but the threads are multiplexed
+#          across the different clients.
+#
+# The default is sync because on Windows hsha is about 30% slower.  On Linux,
+# sync/hsha performance is about the same, with hsha of course using less memory.
+rpc_server_type: sync
+
+# Uncomment rpc_min|max|thread to set request pool size.
+# You would primarily set max for the sync server to safeguard against
+# misbehaved clients; if you do hit the max, Cassandra will block until one
+# disconnects before accepting more.  The defaults for sync are min of 16 and max
+# unlimited.
+#
+# For the Hsha server, the min and max both default to quadruple the number of
+# CPU cores.
+#
+# This configuration is ignored by the async server.
+#
+# rpc_min_threads: 16
+# rpc_max_threads: 2048
+
+# uncomment to set socket buffer sizes on rpc connections
+# rpc_send_buff_size_in_bytes:
+# rpc_recv_buff_size_in_bytes:
+
+# Frame size for thrift (maximum field length).
+# 0 disables TFramedTransport in favor of TSocket. This option
+# is deprecated; we strongly recommend using Framed mode.
+thrift_framed_transport_size_in_mb: 15
+
+# The max length of a thrift message, including all fields and
+# internal thrift overhead.
+thrift_max_message_length_in_mb: 16
+
+# Set to true to have Cassandra create a hard link to each sstable
+# flushed or streamed locally in a backups/ subdirectory of the
+# Keyspace data.  Removing these links is the operator's
+# responsibility.
+incremental_backups: false
+
+# Whether or not to take a snapshot before each compaction.  Be
+# careful using this option, since Cassandra won't clean up the
+# snapshots for you.  Mostly useful if you're paranoid when there
+# is a data format change.
+snapshot_before_compaction: false
+
+# Whether or not a snapshot is taken of the data before keyspace truncation
+# or dropping of column families. The STRONGLY advised default of true
+# should be used to provide data safety. If you set this flag to false, you will
+# lose data on truncation or drop.
+auto_snapshot: false
+
+# Add column indexes to a row after its contents reach this size.
+# Increase if your column values are large, or if you have a very large
+# number of columns.  The competing causes are, Cassandra has to
+# deserialize this much of the row to read a single column, so you want
+# it to be small - at least if you do many partial-row reads - but all
+# the index data is read for each access, so you don't want to generate
+# that wastefully either.
+column_index_size_in_kb: 64
+
+# Size limit for rows being compacted in memory.  Larger rows will spill
+# over to disk and use a slower two-pass compaction process.  A message
+# will be logged specifying the row key.
+#in_memory_compaction_limit_in_mb: 64
+
+# Number of simultaneous compactions to allow, NOT including
+# validation "compactions" for anti-entropy repair.  Simultaneous
+# compactions can help preserve read performance in a mixed read/write
+# workload, by mitigating the tendency of small sstables to accumulate
+# during a single long running compactions. The default is usually
+# fine and if you experience problems with compaction running too
+# slowly or too fast, you should look at
+# compaction_throughput_mb_per_sec first.
+#
+# This setting has no effect on LeveledCompactionStrategy.
+#
+# concurrent_compactors defaults to the number of cores.
+# Uncomment to make compaction mono-threaded, the pre-0.8 default.
+#concurrent_compactors: 1
+
+# Multi-threaded compaction. When enabled, each compaction will use
+# up to one thread per core, plus one thread per sstable being merged.
+# This is usually only useful for SSD-based hardware: otherwise,
+# your concern is usually to get compaction to do LESS i/o (see:
+# compaction_throughput_mb_per_sec), not more.
+#multithreaded_compaction: false
+
+# Throttles compaction to the given total throughput across the entire
+# system. The faster you insert data, the faster you need to compact in
+# order to keep the sstable count down, but in general, setting this to
+# 16 to 32 times the rate you are inserting data is more than sufficient.
+# Setting this to 0 disables throttling. Note that this account for all types
+# of compaction, including validation compaction.
+compaction_throughput_mb_per_sec: 16
+
+# Track cached row keys during compaction, and re-cache their new
+# positions in the compacted sstable.  Disable if you use really large
+# key caches.
+#compaction_preheat_key_cache: true
+
+# Throttles all outbound streaming file transfers on this node to the
+# given total throughput in Mbps. This is necessary because Cassandra does
+# mostly sequential IO when streaming data during bootstrap or repair, which
+# can lead to saturating the network connection and degrading rpc performance.
+# When unset, the default is 200 Mbps or 25 MB/s.
+# stream_throughput_outbound_megabits_per_sec: 200
+
+# How long the coordinator should wait for read operations to complete
+read_request_timeout_in_ms: 5000
+# How long the coordinator should wait for seq or index scans to complete
+range_request_timeout_in_ms: 10000
+# How long the coordinator should wait for writes to complete
+write_request_timeout_in_ms: 2000
+# How long a coordinator should continue to retry a CAS operation
+# that contends with other proposals for the same row
+cas_contention_timeout_in_ms: 1000
+# How long the coordinator should wait for truncates to complete
+# (This can be much longer, because unless auto_snapshot is disabled
+# we need to flush first so we can snapshot before removing the data.)
+truncate_request_timeout_in_ms: 60000
+# The default timeout for other, miscellaneous operations
+request_timeout_in_ms: 10000
+
+# Enable operation timeout information exchange between nodes to accurately
+# measure request timeouts.  If disabled, replicas will assume that requests
+# were forwarded to them instantly by the coordinator, which means that
+# under overload conditions we will waste that much extra time processing
+# already-timed-out requests.
+#
+# Warning: before enabling this property make sure to ntp is installed
+# and the times are synchronized between the nodes.
+cross_node_timeout: false
+
+# Enable socket timeout for streaming operation.
+# When a timeout occurs during streaming, streaming is retried from the start
+# of the current file. This _can_ involve re-streaming an important amount of
+# data, so you should avoid setting the value too low.
+# Default value is 0, which never timeout streams.
+# streaming_socket_timeout_in_ms: 0
+
+# phi value that must be reached for a host to be marked down.
+# most users should never need to adjust this.
+# phi_convict_threshold: 8
+
+# endpoint_snitch -- Set this to a class that implements
+# IEndpointSnitch.  The snitch has two functions:
+# - it teaches Cassandra enough about your network topology to route
+#   requests efficiently
+# - it allows Cassandra to spread replicas around your cluster to avoid
+#   correlated failures. It does this by grouping machines into
+#   "datacenters" and "racks."  Cassandra will do its best not to have
+#   more than one replica on the same "rack" (which may not actually
+#   be a physical location)
+#
+# IF YOU CHANGE THE SNITCH AFTER DATA IS INSERTED INTO THE CLUSTER,
+# YOU MUST RUN A FULL REPAIR, SINCE THE SNITCH AFFECTS WHERE REPLICAS
+# ARE PLACED.
+#
+# Out of the box, Cassandra provides
+#  - SimpleSnitch:
+#    Treats Strategy order as proximity. This improves cache locality
+#    when disabling read repair, which can further improve throughput.
+#    Only appropriate for single-datacenter deployments.
+#  - PropertyFileSnitch:
+#    Proximity is determined by rack and data center, which are
+#    explicitly configured in cassandra-topology.properties.
+#  - RackInferringSnitch:
+#    Proximity is determined by rack and data center, which are
+#    assumed to correspond to the 3rd and 2nd octet of each node's
+#    IP address, respectively.  Unless this happens to match your
+#    deployment conventions (as it did Facebook's), this is best used
+#    as an example of writing a custom Snitch class.
+#  - Ec2Snitch:
+#    Appropriate for EC2 deployments in a single Region.  Loads Region
+#    and Availability Zone information from the EC2 API. The Region is
+#    treated as the Datacenter, and the Availability Zone as the rack.
+#    Only private IPs are used, so this will not work across multiple
+#    Regions.
+#  - Ec2MultiRegionSnitch:
+#    Uses public IPs as broadcast_address to allow cross-region
+#    connectivity.  (Thus, you should set seed addresses to the public
+#    IP as well.) You will need to open the storage_port or
+#    ssl_storage_port on the public IP firewall.  (For intra-Region
+#    traffic, Cassandra will switch to the private IP after
+#    establishing a connection.)
+#
+# You can use a custom Snitch by setting this to the full class name
+# of the snitch, which will be assumed to be on your classpath.
+endpoint_snitch: SimpleSnitch
+
+# controls how often to perform the more expensive part of host score
+# calculation
+dynamic_snitch_update_interval_in_ms: 100
+# controls how often to reset all host scores, allowing a bad host to
+# possibly recover
+dynamic_snitch_reset_interval_in_ms: 600000
+# if set greater than zero and read_repair_chance is < 1.0, this will allow
+# 'pinning' of replicas to hosts in order to increase cache capacity.
+# The badness threshold will control how much worse the pinned host has to be
+# before the dynamic snitch will prefer other replicas over it.  This is
+# expressed as a double which represents a percentage.  Thus, a value of
+# 0.2 means Cassandra would continue to prefer the static snitch values
+# until the pinned host was 20% worse than the fastest.
+dynamic_snitch_badness_threshold: 0.1
+
+# request_scheduler -- Set this to a class that implements
+# RequestScheduler, which will schedule incoming client requests
+# according to the specific policy. This is useful for multi-tenancy
+# with a single Cassandra cluster.
+# NOTE: This is specifically for requests from the client and does
+# not affect inter node communication.
+# org.apache.cassandra.scheduler.NoScheduler - No scheduling takes place
+# org.apache.cassandra.scheduler.RoundRobinScheduler - Round robin of
+# client requests to a node with a separate queue for each
+# request_scheduler_id. The scheduler is further customized by
+# request_scheduler_options as described below.
+request_scheduler: org.apache.cassandra.scheduler.NoScheduler
+
+# Scheduler Options vary based on the type of scheduler
+# NoScheduler - Has no options
+# RoundRobin
+#  - throttle_limit -- The throttle_limit is the number of in-flight
+#                      requests per client.  Requests beyond
+#                      that limit are queued up until
+#                      running requests can complete.
+#                      The value of 80 here is twice the number of
+#                      concurrent_reads + concurrent_writes.
+#  - default_weight -- default_weight is optional and allows for
+#                      overriding the default which is 1.
+#  - weights -- Weights are optional and will default to 1 or the
+#               overridden default_weight. The weight translates into how
+#               many requests are handled during each turn of the
+#               RoundRobin, based on the scheduler id.
+#
+# request_scheduler_options:
+#    throttle_limit: 80
+#    default_weight: 5
+#    weights:
+#      Keyspace1: 1
+#      Keyspace2: 5
+
+# request_scheduler_id -- An identifer based on which to perform
+# the request scheduling. Currently the only valid option is keyspace.
+# request_scheduler_id: keyspace
+
+# index_interval controls the sampling of entries from the primrary
+# row index in terms of space versus time.  The larger the interval,
+# the smaller and less effective the sampling will be.  In technicial
+# terms, the interval coresponds to the number of index entries that
+# are skipped between taking each sample.  All the sampled entries
+# must fit in memory.  Generally, a value between 128 and 512 here
+# coupled with a large key cache size on CFs results in the best trade
+# offs.  This value is not often changed, however if you have many
+# very small rows (many to an OS page), then increasing this will
+# often lower memory usage without a impact on performance.
+index_interval: 128
+
+# Enable or disable inter-node encryption
+# Default settings are TLS v1, RSA 1024-bit keys (it is imperative that
+# users generate their own keys) TLS_RSA_WITH_AES_128_CBC_SHA as the cipher
+# suite for authentication, key exchange and encryption of the actual data transfers.
+# NOTE: No custom encryption options are enabled at the moment
+# The available internode options are : all, none, dc, rack
+#
+# If set to dc cassandra will encrypt the traffic between the DCs
+# If set to rack cassandra will encrypt the traffic between the racks
+#
+# The passwords used in these options must match the passwords used when generating
+# the keystore and truststore.  For instructions on generating these files, see:
+# http://download.oracle.com/javase/6/docs/technotes/guides/security/jsse/JSSERefGuide.html#CreateKeystore
+#
+encryption_options:
+    internode_encryption: none
+    keystore: conf/.keystore
+    keystore_password: cassandra
+    truststore: conf/.truststore
+    truststore_password: cassandra
+    # More advanced defaults below:
+    # protocol: TLS
+    # algorithm: SunX509
+    # store_type: JKS
+    # cipher_suites: [TLS_RSA_WITH_AES_128_CBC_SHA,TLS_RSA_WITH_AES_256_CBC_SHA]

persistence-modules/spring-data-cassandra/src/test/java/org/baeldung/SpringContextTest.java

@@ -0,0 +1,67 @@
+package org.baeldung;
+
+import java.io.IOException;
+import java.util.HashMap;
+
+import org.apache.cassandra.exceptions.ConfigurationException;
+import org.apache.thrift.transport.TTransportException;
+import org.baeldung.spring.data.cassandra.config.CassandraConfig;
+import org.baeldung.spring.data.cassandra.model.Book;
+import org.cassandraunit.utils.EmbeddedCassandraServerHelper;
+import org.junit.After;
+import org.junit.AfterClass;
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.cassandra.core.cql.CqlIdentifier;
+import org.springframework.data.cassandra.core.CassandraAdminOperations;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+import com.datastax.driver.core.Cluster;
+import com.datastax.driver.core.Session;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(classes = CassandraConfig.class)
+public class SpringContextTest {
+
+    public static final String KEYSPACE_CREATION_QUERY = "CREATE KEYSPACE IF NOT EXISTS testKeySpace " + "WITH replication = { 'class': 'SimpleStrategy', 'replication_factor': '3' };";
+
+    public static final String KEYSPACE_ACTIVATE_QUERY = "USE testKeySpace;";
+
+    public static final String DATA_TABLE_NAME = "book";
+	
+	@Autowired
+    private CassandraAdminOperations adminTemplate;
+    
+    @BeforeClass
+    public static void startCassandraEmbedded() throws InterruptedException, TTransportException, ConfigurationException, IOException {
+        EmbeddedCassandraServerHelper.startEmbeddedCassandra();
+        final Cluster cluster = Cluster.builder().addContactPoints("127.0.0.1").withPort(9142).build();
+        final Session session = cluster.connect();
+        session.execute(KEYSPACE_CREATION_QUERY);
+        session.execute(KEYSPACE_ACTIVATE_QUERY);
+        Thread.sleep(5000);
+    }
+
+    @Before
+    public void createTable() throws InterruptedException, TTransportException, ConfigurationException, IOException {
+        adminTemplate.createTable(true, CqlIdentifier.cqlId(DATA_TABLE_NAME), Book.class, new HashMap<String, Object>());
+    }
+    
+	@Test
+    public void whenSpringContextIsBootstrapped_thenNoExceptions() {
+    }
+	
+	@After
+    public void dropTable() {
+        adminTemplate.dropTable(CqlIdentifier.cqlId(DATA_TABLE_NAME));
+    }
+
+    @AfterClass
+    public static void stopCassandraEmbedded() {
+        EmbeddedCassandraServerHelper.cleanEmbeddedCassandra();
+    }
+}

persistence-modules/spring-data-dynamodb/src/test/java/org/baeldung/SpringContextTest.java

@@ -0,0 +1,17 @@
+package org.baeldung;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import com.baeldung.Application;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(classes = Application.class)
+public class SpringContextTest {
+
+    @Test
+    public void whenSpringContextIsBootstrapped_thenNoExceptions() {
+    }
+}

persistence-modules/spring-data-eclipselink/src/test/java/org/baeldung/SpringContextTest.java

@@ -0,0 +1,17 @@
+package org.baeldung;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import com.baeldung.eclipselink.springdata.EclipselinkSpringDataApplication;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(classes = EclipselinkSpringDataApplication.class)
+public class SpringContextTest {
+
+    @Test
+    public void whenSpringContextIsBootstrapped_thenNoExceptions() {
+    }
+}

persistence-modules/spring-data-gemfire/src/test/java/org/baeldung/SpringContextTest.java

@@ -0,0 +1,18 @@
+package org.baeldung;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.support.AnnotationConfigContextLoader;
+
+import com.baeldung.spring.data.gemfire.function.GemfireConfiguration;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(classes=GemfireConfiguration.class, loader=AnnotationConfigContextLoader.class)
+public class SpringContextTest {
+
+    @Test
+    public void whenSpringContextIsBootstrapped_thenNoExceptions() {
+    }
+}

persistence-modules/spring-data-jpa-2/README.md

@@ -1,7 +1,3 @@
-=========
-
-## Spring Data JPA Example Project
-
 ### Relevant Articles: 
 - [Spring Data JPA – Derived Delete Methods](https://www.baeldung.com/spring-data-jpa-deleteby)
 - [JPA Join Types](https://www.baeldung.com/jpa-join-types)
@@ -15,3 +11,5 @@
 - [Spring Data JPA and Named Entity Graphs](https://www.baeldung.com/spring-data-jpa-named-entity-graphs)
 - [Batch Insert/Update with Hibernate/JPA](https://www.baeldung.com/jpa-hibernate-batch-insert-update)
 - [Difference Between save() and saveAndFlush() in Spring Data JPA](https://www.baeldung.com/spring-data-jpa-save-saveandflush)
+- [Derived Query Methods in Spring Data JPA Repositories](https://www.baeldung.com/spring-data-derived-queries)
+- [LIKE Queries in Spring JPA Repositories](https://www.baeldung.com/spring-jpa-like-queries)