How to bind an entity to a specific persistence-unit
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26-09-2019 - |
Question
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.
OTHER TIPS
What you're looking for is probably <exclude-unlisted-classes>true</exclude-unlisted-classes>
.
Check the documentation on jboss.org:
In my configuration I had two databases (let's say A and B) and I wanted two separate persistence units, where one contains all entities, but one, while the other persistence unit contains the remaining entity. My persistence.xml looks like this:
<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="A" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<properties>
<property name="hibernate.dialect" value="${hibernate.dialect}" />
</properties>
</persistence-unit>
<persistence-unit name="B" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<exclude-unlisted-classes>true</exclude-unlisted-classes>
<properties>
<property name="hibernate.dialect" value="${rud.hibernate.dialect}"/>
</properties>
<class>com.sgk.Person</class>
</persistence-unit>
@Pascal Thivent
I haven't tried using multiple EntityManager at once, but looking at above mentioned problem this may help if it works.
@PersistenceContext(unitName="MyPu1")
EntityManager em1;
@PersistenceContext(unitName="MyPu2")
EntityManager em2;