Learning resource for Configuring Hibernate JPA 2.

问题:

I am trying to create a new Java EE project using hibernate and JPA 2.0 on the glass fish server. Can you guys provide me some resources to configure the above so that they work seamlessly? I have tried using netbeans and generated the persistence unit by using the hibernate provider, but I end up getting this error:

javax.persistence.PersistenceException: [PersistenceUnit: DBAppPU] Unable to build EntityManagerFactory

回答1:

First, install Hibernate support via the update tool (or follow the manual procedure). Second, provide a JPA 2.0 persistence.xml to use Hibernate as JPA provider:

<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="MyPu" transaction-type="JTA">
    <provider>org.hibernate.ejb.HibernatePersistence</provider>
    <!-- JNDI name of the database resource to use -->
    <jta-data-source>jdbc/__default</jta-data-source>
    <properties>
      <!-- The database dialect to use -->
      <property name="hibernate.dialect" value="org.hibernate.dialect.DerbyDialect" />
      <!-- update database tables at deployment -->
      <property name="hibernate.hbm2ddl.auto" value="update"/>
      <!-- log the generated SQL -->
      <property name="hibernate.show_sql" value="true"/>
    </properties>
  </persistence-unit>
</persistence>

Resources

• Using Hibernate as JPA Provider for GlassFish V3 (via update tool)
• Use Hibernate as a persistence provider with Glassfish (manual procedure)
• JPA with Hibernate on Glassfish 3

回答2:

This guidance is for integrating hibernate.4.3.5 and EJB and GlassFish.4.0 in NetBeans.8.0 IDE. Create a web project in net beans and add hibernate jar files to the project,other setting related to configuring MySql and glassfish is very simple so I do not describe in this article then create persistence.xml file as follow :

<persistence-unit name="omidashouriPU" transaction-type="Resource_Local">
    <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
    <exclude-unlisted-classes>false</exclude-unlisted-classes>
    <properties>
            <property name="hibernate.archive.autodetection" value="class"/>
            <property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/>
            <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
            <property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/YourSchemaName"/>
            <property name="hibernate.connection.username" value="root"/>
            <property name="hibernate.connection.password" value="yourpassword"/>
            <property name="hibernate.show_sql" value="true"/>
    </properties>
</persistence-unit>

In Your EJB class (class that annotated with @Stateless) for creating EntityManager use following syntax :

EntityManagerFactory emf = Persistence.createEntityManagerFactory("omidashouriPU");
EntityManager em = emf.createEntityManager();
em = emf.createEntityManager();
em.getTransaction().begin();
em.persist(YourEntityObject);
em.getTransaction().end();

As you Know when you are using “transaction-type="Resource_Local", you have to manage the transaction by yourself, mean that, managing of opening and closing the transaction is our responsibility.