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javahibernatejpaejb-3.0persistence-unit

How to bind an entity to a specific persistence-unit


In a web application using struts2 ejb hibernate, is it possible to tell the application to find or create an entity for a specific persistence-unit name, which is written in persistence.xml file, in the deployment time?

I have two persistence-unit in persistence.xml, and one datasource (including two "local-tx-datasource") xml file under the jboss node.

To clearify, I mean, I tried this;

@Entity  
@PersistenceContext(unitName="MY JNDI NAME specified in persistence.xml") 
public abstract class Vehicle {

and doesnt work.. Then tried this and etc..

@PersistenceContext(name="MY PERSISTENCE UNIT NAME specified in persistence.xml")

@PersistenceUnit(name="MY PERSISTENCE UNIT NAME specified in persistence.xml")

and also I tried these above with the "UnitName=.." instead of "name=.." but anything is worked for me...

[SOLVED]

<.exclude-unlisted-classes>true<./exclude-unlisted-classes> has solved my problem


Solution

  • Update: Based on your comment (this is not what I understood from the original question), I don't think you have any other option than disabling "discovery" and listing explicitly your entities in their respective persistence unit:

    <?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="MyPu1" transaction-type="RESOURCE_LOCAL">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <class>com.mycompany.Foo</class>
        ...
        <exclude-unlisted-classes>true</exclude-unlisted-classes>
        <properties>
          <!-- H2 in memory -->
          <property name="javax.persistence.jdbc.driver" value="org.h2.Driver"/>
          <property name="javax.persistence.jdbc.url" value="jdbc:h2:mem:test"/>
          <property name="javax.persistence.jdbc.username" value="APP"/>
          <property name="javax.persistence.jdbc.password" value="APP"/>
          <property name="hibernate.hbm2ddl.auto" value="update"/>
        </properties>
      </persistence-unit>
    
      <persistence-unit name="MyPu2" transaction-type="RESOURCE_LOCAL">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <class>com.mycompany.Bar</class>
        ...
        <exclude-unlisted-classes>true</exclude-unlisted-classes>
        <properties>
          <!-- Derby server -->
          <property name="javax.persistence.jdbc.driver" value="org.apache.derby.jdbc.ClientDriver"/>
          <property name="javax.persistence.jdbc.user" value="APP"/>
          <property name="javax.persistence.jdbc.password" value="APP"/>
          <property name="javax.persistence.jdbc.url" value="jdbc:derby://localhost:1527/Pu2;create=true"/>
          <property name="hibernate.hbm2ddl.auto" value="update"/>
        </properties>
      </persistence-unit>
    </persistence>
    

    I'm not aware of any syntax at the entity level allowing to assign it to a persistence unit.


    I'm not sure I understood what you're trying to do but if you want to get an Entity Manager for a specific persistence unit injected, you should do:

    @Stateless
    public class FooBean implements Foo {
        @PersistenceContext(unitName="MyPu1")
        EntityManager em1;
    
        // ...
    }
    

    If this is not what you want, please clarify the question.