BAEL-6265: PersistenceUnit vs PersistenceContext

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

@@ -0,0 +1,68 @@
+<?xml version="1.0"?>
+<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>hibernate-jpa-2</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>hibernate-jpa-2</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>persistence-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.hibernate.orm</groupId>
+            <artifactId>hibernate-core</artifactId>
+            <version>${hibernate.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+            <version>${spring-boot.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-data-jpa</artifactId>
+            <version>${spring-boot.version}</version>
+            <exclusions>
+                <exclusion>
+                    <groupId>com.zaxxer</groupId>
+                    <artifactId>HikariCP</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <version>${spring-boot.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.h2database</groupId>
+            <artifactId>h2</artifactId>
+            <version>${h2.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.hibernate</groupId>
+            <artifactId>hibernate-spatial</artifactId>
+            <version>${hibernate.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.hibernate</groupId>
+            <artifactId>hibernate-testing</artifactId>
+            <version>${hibernate.version}</version>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <hibernate.version>6.4.2.Final</hibernate.version>
+        <spring-boot.version>3.0.4</spring-boot.version>
+        <h2.version>2.1.214</h2.version>
+        <org.slf4j.version>2.0.7</org.slf4j.version>
+        <logback.version>1.4.6</logback.version>
+    </properties>
+
+</project>

persistence-modules/hibernate-jpa-2/src/main/java/com/baeldung/contextvsunit/PersistenceContextVsUnitApplication.java

@@ -0,0 +1,15 @@
+package com.baeldung.contextvsunit;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.ComponentScan;
+
+@SpringBootApplication
+@ComponentScan(basePackages = "com.baeldung.contextvsunit")
+public class PersistenceContextVsUnitApplication {
+
+    public static void main(String[] args) {
+        SpringApplication.run(PersistenceContextVsUnitApplication.class, args);
+    }
+
+}

persistence-modules/hibernate-jpa-2/src/main/java/com/baeldung/contextvsunit/entity/Product.java

@@ -0,0 +1,52 @@
+package com.baeldung.contextvsunit.entity;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.Id;
+import jakarta.persistence.Table;
+
+@Entity
+@Table(name = "PRODUCT")
+public class Product {
+
+    @Id
+    private Long id;
+
+    private String name;
+
+    private double price;
+
+    public Product() {
+
+    }
+
+    public Product(Long id, String name, double price) {
+        this.id = id;
+        this.name = name;
+        this.price = price;
+    }
+
+    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 double getPrice() {
+        return price;
+    }
+
+    public void setPrice(double price) {
+        this.price = price;
+    }
+
+}

persistence-modules/hibernate-jpa-2/src/main/java/com/baeldung/contextvsunit/service/PersistenceContextProductService.java

@@ -0,0 +1,38 @@
+package com.baeldung.contextvsunit.service;
+
+import org.springframework.stereotype.Service;
+
+import com.baeldung.contextvsunit.entity.Product;
+
+import jakarta.persistence.EntityManager;
+import jakarta.persistence.PersistenceContext;
+import jakarta.persistence.PersistenceContextType;
+import jakarta.transaction.Transactional;
+
+@Service
+public class PersistenceContextProductService {
+
+    @PersistenceContext(type = PersistenceContextType.TRANSACTION)
+    private EntityManager entityManagerTransactionType;
+
+    @PersistenceContext(type = PersistenceContextType.EXTENDED)
+    private EntityManager entityManagerExtendedType;
+
+    @Transactional
+    public void insertProductWithTransactionTypePersistenceContext(Product product) {
+        entityManagerTransactionType.persist(product);
+    }
+
+    public Product findWithTransactionTypePersistenceContext(long id) {
+        return entityManagerTransactionType.find(Product.class, id);
+    }
+
+    public void insertProductWithExtendedTypePersistenceContext(Product product) {
+        entityManagerExtendedType.persist(product);
+    }
+
+    public Product findWithExtendedTypePersistenceContext(long id) {
+        return entityManagerExtendedType.find(Product.class, id);
+    }
+
+}

persistence-modules/hibernate-jpa-2/src/main/java/com/baeldung/contextvsunit/service/PersistenceUnitProductService.java

@@ -0,0 +1,28 @@
+package com.baeldung.contextvsunit.service;
+
+import org.springframework.stereotype.Service;
+
+import com.baeldung.contextvsunit.entity.Product;
+
+import jakarta.persistence.EntityManager;
+import jakarta.persistence.EntityManagerFactory;
+import jakarta.persistence.PersistenceUnit;
+import jakarta.transaction.Transactional;
+
+@Service
+public class PersistenceUnitProductService {
+
+    @PersistenceUnit(name = "com.baeldung.contextvsunit.h2_persistence_unit")
+    private EntityManagerFactory emf;
+
+    @Transactional
+    public void insertProduct(Product product) {
+        EntityManager entityManager = emf.createEntityManager();
+        entityManager.persist(product);
+    }
+
+    public Product find(long id) {
+        EntityManager entityManager = emf.createEntityManager();
+        return entityManager.find(Product.class, id);
+    }
+}

persistence-modules/hibernate-jpa-2/src/main/resources/META-INF/persistence.xml

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<persistence xmlns="http://java.sun.com/xml/ns/persistence"
+             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+             xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
+             version="2.0">
+    <persistence-unit name="com.baeldung.contextvsunit.h2_persistence_unit" transaction-type="RESOURCE_LOCAL">
+        <description>EntityManager serializable persistence unit</description>
+        <class>com.baeldung.contextvsunit.entity.Product</class>
+        <exclude-unlisted-classes>true</exclude-unlisted-classes>
+        <properties>
+            <property name="hibernate.hbm2ddl.auto" value="update"/>
+            <property name="hibernate.show_sql" value="true"/>
+            <property name="hibernate.generate_statistics" value="false"/>
+            <property name="hibernate.dialect" value="org.hibernate.dialect.H2Dialect"/>
+            <property name="jakarta.persistence.jdbc.driver" value="org.h2.Driver"/>
+            <property name="jakarta.persistence.jdbc.url" value="jdbc:h2:mem:db2;DB_CLOSE_DELAY=-1"/>
+            <property name="jakarta.persistence.jdbc.user" value="sa"/>
+            <property name="jakarta.persistence.jdbc.password" value=""/>
+        </properties>
+    </persistence-unit>
+
+</persistence> 

persistence-modules/hibernate-jpa-2/src/main/resources/logback.xml

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

persistence-modules/hibernate-jpa-2/src/test/java/com/baeldung/contextvsunit/PersistenceContextVsUnitProductServiceTest.java

@@ -0,0 +1,57 @@
+package com.baeldung.contextvsunit;
+
+import static org.junit.Assert.assertNotNull;
+
+import org.junit.Test;
+import org.junit.jupiter.api.Assertions;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import com.baeldung.contextvsunit.entity.Product;
+import com.baeldung.contextvsunit.service.PersistenceContextProductService;
+import com.baeldung.contextvsunit.service.PersistenceUnitProductService;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(classes = com.baeldung.contextvsunit.PersistenceContextVsUnitApplication.class)
+public class PersistenceContextVsUnitProductServiceTest {
+
+    @Autowired
+    private PersistenceContextProductService persistenceContextProductService;
+    @Autowired
+    private PersistenceUnitProductService persistenceUnitProductService;
+
+    @Test
+    public void whenProductPersistWithTransactionPersistenceContext_thenShouldPersist() {
+        Product p = new Product(1L, "Product 1", 100.0);
+        persistenceContextProductService.insertProductWithTransactionTypePersistenceContext(p);
+
+        Product productFromTransactionScoped = persistenceContextProductService.findWithTransactionTypePersistenceContext(1L);
+        Assertions.assertNotNull(productFromTransactionScoped);
+
+        Product productFromExtendedScoped = persistenceContextProductService.findWithExtendedTypePersistenceContext(1L);
+        Assertions.assertNotNull(productFromExtendedScoped);
+    }
+
+    @Test
+    public void whenProductPersistWithExtendedPersistence_thenShouldPersist() {
+        Product product = new Product(2L, "Product 1", 100.0);
+        persistenceContextProductService.insertProductWithExtendedTypePersistenceContext(product);
+
+        Product productFromExtendedScoped = persistenceContextProductService.findWithExtendedTypePersistenceContext(2L);
+        Assertions.assertNotNull(productFromExtendedScoped);
+
+        Product productFromTransactionScoped = persistenceContextProductService.findWithTransactionTypePersistenceContext(2L);
+        Assertions.assertNull(productFromTransactionScoped);
+    }
+
+    @Test
+    public void whenProductPersistWithEntityManagerFactory_thenShouldPersist() {
+        Product p = new Product(1L, "Product 1", 100.0);
+        persistenceUnitProductService.insertProduct(p);
+
+        Product createdProduct = persistenceUnitProductService.find(1L);
+        assertNotNull(createdProduct);
+    }
+}

persistence-modules/hibernate-jpa-2/src/test/resources/hibernate.properties

@@ -0,0 +1,17 @@
+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
+
+# enable to see Hibernate generated SQL
+hibernate.show_sql=false
+
+hibernate.hbm2ddl.auto=create-drop
+
+hibernate.c3p0.min_size=5
+hibernate.c3p0.max_size=20
+hibernate.c3p0.acquire_increment=5
+hibernate.c3p0.timeout=1800

persistence-modules/pom.xml

@@ -35,6 +35,7 @@
         <module>hibernate-exceptions</module>
         <module>hibernate-libraries</module>
         <module>hibernate-jpa</module>
+        <module>hibernate-jpa-2</module>
         <module>hibernate-queries</module>
         <module>hibernate-enterprise</module>
         <module>influxdb</module>