How to configure JPA project

Agenda:
  1. Creating JPA project and generating entities.
  2. Configuring persistence properties and JPA project
  3. Testing the JPA project

  4. Update database when entity changed.
  5. Setting up load balance database connection.
  6. Setting Cache Coordination in Eclipselink

This post shows how to configure the JPA project about its' persistence properties after entities successfully generated in a JPA project.

Before we start to configure our JPA project, first we must decide which JPA implementation to use.
There are two(2) popular JPA implementations, which are EclipseLink and Hibernate.

Once the preferred JPA implementation installed, then we can start to configure the persistence properties.

Steps:

1. Install JPA implementation library

1.1 EclipseLink

      a) download the required EclipseLink library, and the version that I used in this tutorial is 2.4.1

      b) unzip the archive

      c) copy the javax.persistence_2.0.4.v201112161009.jar and eclipselink.jar to a folder (eg, c:\eclipselink-lib)

      d) create a user libraries name eclipselink in eclipse, and add all above jar into this user library.

      e) create a user libraries for the target jdbc driver, and add the jdbc jar into this user library

     f) add these 2 user libraries to the JPA project.

1.2 Hibernate

      a) download the required Hibernate Library, and the version that I used in this tutorial is 4.2.0

      b) unzip the archive

      c) copy the jar files below to a folder (eg, c:\eclipselink-lib\hibernate)
          - antlr-2.7.7.jar
          - dom4j-1.6.1.jar
          - hibernate-commons-annotations-4.0.1.Finall.jar
          - hibernate-core-4.2.0.Final.jar
          - hibernate-entitymanager-4.2.0.Final.jar
          - hibernate-jpa-2.0-api-1.0.1.Final.jar
          - javassist-3.15.0-GA.jar
          - jboss-logging-3.1.0.GA.jar
          - jboss-transaction-api_1.1_spec-1.0.0.Final.jar

      d) create a user libraries name hibernate in eclipse, and add all above jar into this user library.

      e) create a user libraries for the target jdbc driver, and add the jdbc jar into this user library

     f) add these 2 user libraries to the JPA project.

    at this stage, all the Eclipse compilation errors should be gone.

2. configure persistence properties in persistence.xml.

    a) d-click to open persistence.xml in <JPA_Project>/src/META-INF

    b) in General tab, fill in Persistence provider by your choice of JPA implementation.

EclipseLink	org.eclipse.persistence.jpa.PersistenceProvider
Hibernte	org.hibernate.ejb.HibernatePersistence

    c) in Connection tab, choose Resource Local for Transaction type

    d) Fill in Driver, URL, User, Password or Populate from connection... to choose a configured database connection

   e) save persistence.xml

PREV Generating Entities

Testing the JPA project NEXT

Done!!