Using JPA with Hibernate implementation: entityManager.remove - not working

Question

I am using JPA over Hibernate 4.1.4.Final implementation. My problem is that I can't get EntityManager#remove() working. All other: update, insert, select operation are working just fine except this one.

My persistence.xml file:

<persistence-unit name="myEntityManager">
    <provider>org.hibernate.ejb.HibernatePersistence</provider>
    <class>core.entity.Answer</class>
    <class>core.entity.BaseEntity</class>
    <exclude-unlisted-classes>true</exclude-unlisted-classes>
    <validation-mode>NONE</validation-mode>
    <properties>
        <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
        <property name="hibernate.show_sql" value="true"/>
        <property name="hibernate.hbm2ddl.auto" value="update"/>
    </properties>
</persistence-unit>

My Answer entity: (BaseEntity class just holds the primary key - ID)

@Entity
@Table(name = "ANSWER")
@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
public class Answer extends BaseEntity {

    @Column(name = "ANSWER_VALUE")
    private String answerValue;

    @ManyToOne(fetch = FetchType.EAGER)
    @JoinColumn(name = "QUESTION_ID", nullable = false)
    private Question question;                

    //overrided equals, hascode, toString 
    // all getters and setters
}

When calling:

public void remove(T entity) {
    this.entityManager.remove(this.entityManager.merge(entity));
}

Also tried:

this.entityManager.remove(entity);

And:

T ref = entityManager.getReference(entityClass, primaryKey);
entityManager.remove(ref);

No luck :( it is not deleting the record of Answer from the database.

I am using Spring configuration to configure the entity manager like this:

<bean id="persistenceUnitManager" class="org.springframework.orm.jpa.persistenceunit.DefaultPersistenceUnitManager">
    <property name="persistenceXmlLocations">
        <list>
            <value>classpath*:META-INF/persistence.xml</value>
        </list>
    </property>
    <property name="defaultDataSource" ref="dataSource"/>
</bean>

<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
    <property name="persistenceUnitManager" ref="persistenceUnitManager"/>
    <property name="persistenceUnitName" value="myEntityManager"/>
</bean>

<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
    <property name="entityManagerFactory" ref="entityManagerFactory"/>
</bean>

<tx:annotation-driven proxy-target-class="true" transaction-manager="transactionManager"/>

remove is called in the method which is annotated with @Transactional annotation. So it shouldn't be transactions issue.

I have enabled Hibernate SQL logging, all the other logging. I am not seeing anywhere that delete query would be executed or any error at all.

And I am really out of options here. Please advice.

EDIT

Maybe this will also help:

I am getting the list of answers from the other entity. The answers are defined like this:

@OneToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL, mappedBy = "evaluationPart")
private List<Answer> answers = new LinkedList<>();

Calling remove like this:

List<Answer> answers = evaluationPart.getAnswers();
if (answers != null && answers.size() > 0) {
    for (Answer answer : answers) {
        answerFacade.remove(answer); //This calls enetityManager.remove
    }
}

And your other Create/Update methods all work ok and persist as expected? are those methods in the same class and using the same setup? — rhinds
– rhinds, Commented Mar 28, 2013 at 10:52
Yes. Everything else is working, everything is the same for other operations. — user2219247
– user2219247, Commented Mar 28, 2013 at 10:55
@rhinds I've updated the question. Maybe you'd be able to see the problem now. — user2219247
– user2219247, Commented Mar 28, 2013 at 12:21
No, nothing related to errors at all, no errors, just usual hibernate stuff and SQL.. — user2219247
– user2219247, Commented Mar 28, 2013 at 12:27

Code2Interface · Accepted Answer · 2013-03-28 12:37:28Z

4

I may be out of the topic but these can be the issues for the problem

First Reason - No cascadeType defined in this entry

 @ManyToOne(fetch = FetchType.EAGER)
    @JoinColumn(name = "QUESTION_ID", nullable = false)
    private Question question;

Second Reason (More of a suggestion)

As the linkedlist of Answer is mapped to the Question object, deleting a single object from the list directly is not recommended as a good practice. Better remove the element from the linked list and then update/merge the question object which will perform the remove operation automatically on the Answer table.

Hope this helps :)

answered Mar 28, 2013 at 12:37

Code2Interface

4952 silver badges7 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

user2219247 Over a year ago

No cascade type is defined because I don't want this object to be cascaded in any way :) that's fine. Your second reason gave a way to the solution. Yes I don't need to call entityManager.remove if I am removing it from the list, so that worked. Thanks. Still can't fully understand why hibernate did not clear the persistence context. Maybe because the objects were lazy loaded...

nick.stuart Over a year ago

Just had the same issue, it would be nice if Hibernate would at least yell at you for removing a list item by calling em.remove(ref). Oh well, lesson learned.

Collectives™ on Stack Overflow

Using JPA with Hibernate implementation: entityManager.remove - not working

1 Answer 1

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related