Jump to: navigation, search

EclipseLink/Examples/JPA/Composite

< EclipseLink‎ | Examples‎ | JPA
Revision as of 17:11, 6 June 2011 by Andrei.ilitchev.oracle.com (Talk | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
  • Two or more persistence units could be combined into a single Composite persistence Unit.
  • Each composite members persistence unit keeps mapping its classes to its own database.
    • Therefore Composite persistence unit allows to map different entities to different data bases.
  • Below is an exaple of Composite persistence unit definition.
    • compositePu specifies transaction type and server platform.
    • It contains all persistence units defined in member1.jar and member2.jar files.
<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 persistence_1_0.xsd" version="1.0">
    <persistence-unit name="compositePu" transaction-type="JTA">
        <provider>
            org.eclipse.persistence.jpa.PersistenceProvider
        </provider>
 
        <jar-file>member1.jar</jar-file>
        <jar-file>member2.jar</jar-file>
 
        <properties>
            <property name="eclipselink.composite-unit" value="true"/>
            <property name="eclipselink.target-server" value="WebLogic_10"/>
        </properties>
    </persistence-unit>
</persistence>

For more information about Composite persistence units please see the design doc.