Merge remote-tracking branch 'baeldung/master' into BAEL-3841#declarative-caching-testing

persistence-modules/hibernate-exceptions/pom.xml

@@ -0,0 +1,39 @@
+<?xml version="1.0"?>
+<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>hibernate-exceptions</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>hibernate-exceptions</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>persistence-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.hsqldb</groupId>
+            <artifactId>hsqldb</artifactId>
+            <version>${hsqldb.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.hibernate</groupId>
+            <artifactId>hibernate-core</artifactId>
+            <version>${hibernate.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>javax.xml.bind</groupId>
+            <artifactId>jaxb-api</artifactId>
+            <version>${jaxb.version}</version>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <hsqldb.version>2.4.0</hsqldb.version>
+        <jaxb.version>2.3.0</jaxb.version>
+        <hibernate.version>5.3.7.Final</hibernate.version>
+    </properties>
+
+</project>

persistence-modules/hibernate-exceptions/src/main/java/com/baeldung/hibernate/exception/lazyinitialization/HibernateUtil.java

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+package com.baeldung.hibernate.exception.lazyinitialization;
+
+import java.util.Properties;
+
+import org.hibernate.SessionFactory;
+import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
+import org.hibernate.cfg.Configuration;
+import org.hibernate.cfg.Environment;
+import org.hibernate.service.ServiceRegistry;
+
+import com.baeldung.hibernate.exception.lazyinitialization.entity.Role;
+import com.baeldung.hibernate.exception.lazyinitialization.entity.User;
+
+public class HibernateUtil {
+    private static SessionFactory sessionFactory;
+
+    public static SessionFactory getSessionFactory() {
+        if (sessionFactory == null) {
+            try {
+                Configuration configuration = new Configuration();
+                Properties settings = new Properties();
+                settings.put(Environment.DRIVER, "org.hsqldb.jdbcDriver");
+                settings.put(Environment.URL, "jdbc:hsqldb:mem:userrole");
+                settings.put(Environment.USER, "sa");
+                settings.put(Environment.PASS, "");
+                settings.put(Environment.DIALECT, "org.hibernate.dialect.HSQLDialect");
+                settings.put(Environment.SHOW_SQL, "true");
+                settings.put(Environment.HBM2DDL_AUTO, "update");
+                configuration.setProperties(settings);
+                configuration.addAnnotatedClass(User.class);
+                configuration.addAnnotatedClass(Role.class);
+
+                ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder()
+                        .applySettings(configuration.getProperties()).build();
+                sessionFactory = configuration.buildSessionFactory(serviceRegistry);
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
+        return sessionFactory;
+    }
+}

persistence-modules/hibernate-exceptions/src/main/java/com/baeldung/hibernate/exception/lazyinitialization/entity/Role.java

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+package com.baeldung.hibernate.exception.lazyinitialization.entity;
+
+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 = "role")
+public class Role {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    @Column(name = "id")
+    private int id;
+
+    @Column(name = "role_name")
+    private String roleName;
+
+    public Role() {
+
+    }
+
+    public Role(String roleName) {
+        this.roleName = roleName;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public void setId(int id) {
+        this.id = id;
+    }
+
+    public String getRoleName() {
+        return roleName;
+    }
+
+    public void setRoleName(String roleName) {
+        this.roleName = roleName;
+    }
+
+}

persistence-modules/hibernate-exceptions/src/main/java/com/baeldung/hibernate/exception/lazyinitialization/entity/User.java

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+package com.baeldung.hibernate.exception.lazyinitialization.entity;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.JoinColumn;
+import javax.persistence.OneToMany;
+import javax.persistence.Table;
+
+@Entity
+@Table(name = "user")
+public class User {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    @Column(name = "id")
+    private int id;
+
+    @Column(name = "first_name")
+    private String firstName;
+
+    @Column(name = "last_name")
+    private String lastName;
+
+    @OneToMany
+    @JoinColumn(name = "user_id")
+    private Set<Role> roles = new HashSet<>();
+
+    public User() {
+
+    }
+
+    public User(String firstName, String lastName) {
+        this.firstName = firstName;
+        this.lastName = lastName;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public Set<Role> getRoles() {
+        return roles;
+    }
+
+    public void addRole(Role role) {
+        roles.add(role);
+    }
+
+}

persistence-modules/hibernate-exceptions/src/test/java/com/baeldung/hibernate/exception/lazyinitialization/HibernateNoSessionUnitTest.java

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+package com.baeldung.hibernate.exception.lazyinitialization;
+
+import org.hibernate.LazyInitializationException;
+import org.hibernate.Session;
+import org.hibernate.SessionFactory;
+import org.junit.AfterClass;
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+
+import com.baeldung.hibernate.exception.lazyinitialization.entity.Role;
+import com.baeldung.hibernate.exception.lazyinitialization.entity.User;
+
+public class HibernateNoSessionUnitTest {
+
+    private static SessionFactory sessionFactory;
+
+    @Rule
+    public ExpectedException thrown = ExpectedException.none();
+
+    @BeforeClass
+    public static void init() {
+        sessionFactory = HibernateUtil.getSessionFactory();
+    }
+
+    @Test
+    public void whenAccessUserRolesInsideSession_thenSuccess() {
+
+        User detachedUser = createUserWithRoles();
+
+        Session session = sessionFactory.openSession();
+        session.beginTransaction();
+
+        User persistentUser = session.find(User.class, detachedUser.getId());
+
+        Assert.assertEquals(2, persistentUser.getRoles().size());
+
+        session.getTransaction().commit();
+        session.close();
+    }
+
+    @Test
+    public void whenAccessUserRolesOutsideSession_thenThrownException() {
+
+        User detachedUser = createUserWithRoles();
+
+        Session session = sessionFactory.openSession();
+        session.beginTransaction();
+
+        User persistentUser = session.find(User.class, detachedUser.getId());
+
+        session.getTransaction().commit();
+        session.close();
+
+        thrown.expect(LazyInitializationException.class);
+        System.out.println(persistentUser.getRoles().size());
+    }
+
+    private User createUserWithRoles() {
+
+        Role admin = new Role("Admin");
+        Role dba = new Role("DBA");
+
+        User user = new User("Bob", "Smith");
+
+        user.addRole(admin);
+        user.addRole(dba);
+
+        Session session = sessionFactory.openSession();
+        session.beginTransaction();
+        user.getRoles().forEach(role -> session.save(role));
+        session.save(user);
+        session.getTransaction().commit();
+        session.close();
+
+        return user;
+    }
+
+    @AfterClass
+    public static void cleanUp() {
+        sessionFactory.close();
+    }
+}