BAEL-446: Deleting objects with Hibernate. (#879)

spring-jpa/src/main/java/org/baeldung/config/PersistenceJPAConfigL2Cache.java

@@ -40,7 +40,7 @@ public class PersistenceJPAConfigL2Cache {
     public LocalContainerEntityManagerFactoryBean entityManagerFactory() {
         final LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
         em.setDataSource(dataSource());
-        em.setPackagesToScan(new String[] { "org.baeldung.persistence.model" });
+        em.setPackagesToScan(getPackagesToScan());
 
         final HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
         em.setJpaVendorAdapter(vendorAdapter);
@@ -49,6 +49,10 @@ public class PersistenceJPAConfigL2Cache {
         return em;
     }
 
+    protected String[] getPackagesToScan() {
+        return new String[] { "org.baeldung.persistence.model" };
+    }
+
     @Bean
     public DataSource dataSource() {
         final DriverManagerDataSource dataSource = new DriverManagerDataSource();
@@ -78,6 +82,7 @@ public class PersistenceJPAConfigL2Cache {
         hibernateProperties.setProperty("hibernate.cache.use_second_level_cache", env.getProperty("hibernate.cache.use_second_level_cache"));
         hibernateProperties.setProperty("hibernate.cache.use_query_cache", env.getProperty("hibernate.cache.use_query_cache"));
         hibernateProperties.setProperty("hibernate.cache.region.factory_class", env.getProperty("hibernate.cache.region.factory_class"));
+        hibernateProperties.setProperty("hibernate.show_sql", env.getProperty("hibernate.show_sql"));
         return hibernateProperties;
     }
 

spring-jpa/src/main/resources/persistence-h2.properties

@@ -6,7 +6,7 @@ jdbc.user=sa
 
 # hibernate.X
 hibernate.dialect=org.hibernate.dialect.H2Dialect
-hibernate.show_sql=false
+hibernate.show_sql=true
 hibernate.hbm2ddl.auto=create-drop
 hibernate.cache.use_second_level_cache=true
 hibernate.cache.use_query_cache=true

spring-jpa/src/test/java/org/baeldung/persistence/deletion/config/PersistenceJPAConfigDeletion.java

@@ -0,0 +1,17 @@
+package org.baeldung.persistence.deletion.config;
+
+import org.baeldung.config.PersistenceJPAConfigL2Cache;
+
+import java.util.Properties;
+
+public class PersistenceJPAConfigDeletion extends PersistenceJPAConfigL2Cache {
+
+    public PersistenceJPAConfigDeletion() {
+        super();
+    }
+
+    @Override
+    protected String[] getPackagesToScan() {
+        return new String[] { "org.baeldung.persistence.deletion.model" };
+    }
+}

spring-jpa/src/test/java/org/baeldung/persistence/deletion/model/Bar.java

@@ -0,0 +1,60 @@
+package org.baeldung.persistence.deletion.model;
+
+import javax.persistence.*;
+import java.util.ArrayList;
+import java.util.List;
+
+@Entity
+@Table(name = "BAR")
+public class Bar {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private long id;
+
+    @Column(nullable = false)
+    private String name;
+
+    @OneToMany(cascade = CascadeType.ALL, orphanRemoval = true)
+    List<Baz> bazList = new ArrayList<>();
+
+    public Bar() {
+        super();
+    }
+
+    public Bar(final String name) {
+        super();
+        this.name = name;
+    }
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(final long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(final String name) {
+        this.name = name;
+    }
+
+    public List<Baz> getBazList() {
+        return bazList;
+    }
+
+    public void setBazList(final List<Baz> bazList) {
+        this.bazList = bazList;
+    }
+
+    @Override
+    public String toString() {
+        final StringBuilder builder = new StringBuilder();
+        builder.append("Bar [name=").append(name).append("]");
+        return builder.toString();
+    }
+}

spring-jpa/src/test/java/org/baeldung/persistence/deletion/model/Baz.java

@@ -0,0 +1,48 @@
+package org.baeldung.persistence.deletion.model;
+
+import javax.persistence.*;
+import java.util.List;
+
+@Entity
+@Table(name = "BAZ")
+public class Baz {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    private long id;
+
+    @Column(nullable = false)
+    private String name;
+
+    public Baz() {
+        super();
+    }
+
+    public Baz(final String name) {
+        super();
+        this.name = name;
+    }
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(final long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(final String name) {
+        this.name = name;
+    }
+
+    @Override
+    public String toString() {
+        final StringBuilder builder = new StringBuilder();
+        builder.append("Bar [name=").append(name).append("]");
+        return builder.toString();
+    }
+}

spring-jpa/src/test/java/org/baeldung/persistence/deletion/model/Foo.java

@@ -0,0 +1,63 @@
+package org.baeldung.persistence.deletion.model;
+
+import org.hibernate.annotations.Where;
+
+import javax.persistence.*;
+
+@Entity
+@Table(name = "FOO")
+@Where(clause = "DELETED = 0")
+public class Foo {
+
+    public Foo() {
+        super();
+    }
+
+    public Foo(final String name) {
+        super();
+        this.name = name;
+    }
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.AUTO)
+    @Column(name = "ID")
+    private long id;
+
+    @Column(name = "NAME")
+    private String name;
+
+    @Column(name = "DELETED")
+    private Integer deleted = 0;
+
+    @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
+    @JoinColumn(name = "BAR_ID")
+    private Bar bar;
+
+    public Bar getBar() {
+        return bar;
+    }
+
+    public void setBar(final Bar bar) {
+        this.bar = bar;
+    }
+
+    public long getId() {
+        return id;
+    }
+
+    public void setId(final int id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(final String name) {
+        this.name = name;
+    }
+
+    public void setDeleted() {
+        this.deleted = 1;
+    }
+}

spring-jpa/src/test/java/org/baeldung/persistence/service/DeletionIntegrationTest.java

@@ -0,0 +1,159 @@
+package org.baeldung.persistence.service;
+
+import org.baeldung.persistence.deletion.config.PersistenceJPAConfigDeletion;
+import org.baeldung.persistence.deletion.model.Bar;
+import org.baeldung.persistence.deletion.model.Baz;
+import org.baeldung.persistence.deletion.model.Foo;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.support.AnnotationConfigContextLoader;
+import org.springframework.transaction.PlatformTransactionManager;
+import org.springframework.transaction.annotation.Transactional;
+
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceContext;
+
+import static org.hamcrest.Matchers.notNullValue;
+import static org.hamcrest.Matchers.nullValue;
+import static org.junit.Assert.assertThat;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(classes = { PersistenceJPAConfigDeletion.class }, loader = AnnotationConfigContextLoader.class)
+public class DeletionIntegrationTest {
+
+    @PersistenceContext
+    private EntityManager entityManager;
+    @Autowired
+    private PlatformTransactionManager platformTransactionManager;
+
+    @Before
+    public final void before() {
+        entityManager.getEntityManagerFactory().getCache().evictAll();
+    }
+
+    @Test
+    @Transactional
+    public final void givenEntityIsRemoved_thenItIsNotInDB() {
+        Foo foo = new Foo("foo");
+        entityManager.persist(foo);
+        flushAndClear();
+
+        foo = entityManager.find(Foo.class, foo.getId());
+        assertThat(foo, notNullValue());
+
+        entityManager.remove(foo);
+        flushAndClear();
+
+        assertThat(entityManager.find(Foo.class, foo.getId()), nullValue());
+    }
+
+    @Test
+    @Transactional
+    public final void givenEntityIsRemovedAndReferencedByAnotherEntity_thenItIsNotRemoved() {
+        Bar bar = new Bar("bar");
+        Foo foo = new Foo("foo");
+        foo.setBar(bar);
+        entityManager.persist(foo);
+        flushAndClear();
+
+        foo = entityManager.find(Foo.class, foo.getId());
+        bar = entityManager.find(Bar.class, bar.getId());
+        entityManager.remove(bar);
+        flushAndClear();
+
+        bar = entityManager.find(Bar.class, bar.getId());
+        assertThat(bar, notNullValue());
+
+        foo = entityManager.find(Foo.class, foo.getId());
+        foo.setBar(null);
+        entityManager.remove(bar);
+        flushAndClear();
+
+        assertThat(entityManager.find(Bar.class, bar.getId()), nullValue());
+    }
+
+    @Test
+    @Transactional
+    public final void givenEntityIsRemoved_thenRemovalIsCascaded() {
+        Bar bar = new Bar("bar");
+        Foo foo = new Foo("foo");
+        foo.setBar(bar);
+        entityManager.persist(foo);
+        flushAndClear();
+
+        foo = entityManager.find(Foo.class, foo.getId());
+        entityManager.remove(foo);
+        flushAndClear();
+
+        assertThat(entityManager.find(Foo.class, foo.getId()), nullValue());
+        assertThat(entityManager.find(Bar.class, bar.getId()), nullValue());
+    }
+
+    @Test
+    @Transactional
+    public final void givenEntityIsDisassociated_thenOrphanRemovalIsApplied() {
+        Bar bar = new Bar("bar");
+        Baz baz = new Baz("baz");
+        bar.getBazList().add(baz);
+        entityManager.persist(bar);
+        flushAndClear();
+
+        bar = entityManager.find(Bar.class, bar.getId());
+        baz = bar.getBazList().get(0);
+        bar.getBazList().remove(baz);
+        flushAndClear();
+
+        assertThat(entityManager.find(Baz.class, baz.getId()), nullValue());
+    }
+
+    @Test
+    @Transactional
+    public final void givenEntityIsDeletedWithJpaBulkDeleteStatement_thenItIsNotInDB() {
+        Foo foo = new Foo("foo");
+        entityManager.persist(foo);
+        flushAndClear();
+
+        entityManager.createQuery("delete from Foo where id = :id")
+                .setParameter("id", foo.getId())
+                .executeUpdate();
+
+        assertThat(entityManager.find(Foo.class, foo.getId()), nullValue());
+    }
+
+    @Test
+    @Transactional
+    public final void givenEntityIsDeletedWithNativeQuery_thenItIsNotInDB() {
+        Foo foo = new Foo("foo");
+        entityManager.persist(foo);
+        flushAndClear();
+
+        entityManager.createNativeQuery("delete from FOO where ID = :id")
+                .setParameter("id", foo.getId())
+                .executeUpdate();
+
+        assertThat(entityManager.find(Foo.class, foo.getId()), nullValue());
+    }
+
+    @Test
+    @Transactional
+    public final void givenEntityIsSoftDeleted_thenItIsNotReturnedFromQueries() {
+        Foo foo = new Foo("foo");
+        entityManager.persist(foo);
+        flushAndClear();
+
+        foo = entityManager.find(Foo.class, foo.getId());
+        foo.setDeleted();
+        flushAndClear();
+
+        assertThat(entityManager.find(Foo.class, foo.getId()), nullValue());
+    }
+
+    private void flushAndClear() {
+        entityManager.flush();
+        entityManager.clear();
+    }
+}