Using Eclipselink as a Persistence Provider in a Netbeans/Wildfly project for JTA transaction

Project Versions

 EclipseLink Version: 2.5.2 - [ EclipseLink 2.5.2 == JPA 2.1] 
 JBDC Driver Name             : Oracle JDBC driver
 JDBC Driver Version          : 12.1.0.2.0
 Database Version             : Database Product Version: Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
                                With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
                                Advanced Analytics and Real Application Testing options
 Database Name and Instances  : DB Name:  BANKA
                                1. Instance Name: bankA_2 - Host: hract21.example.com
                                2. Instance Name: bankA_1 - Host: hract22.example.com
 Netbeans Version             : 8.0.2
 Wildfly Version              : 8.2
 Entity Manger Type           : Application Managed
 Transaction Type             : JTA

Setup EclipseLink as a Wildfly Module

Check modules/system/layers/base/org/eclipse/persistence/main directory
oracle@wls1 main]$ pwd
/usr/local/wildfly-8.2.0.Final/modules/system/layers/base/org/eclipse/persistence/main

Copy eclipselink-2.5.2.jar from MAVEN repository  to modules/system/layers/base/org/eclipse/persistence/main
[oracle@wls1 main]$ ls
eclipselink-2.5.2.jar  jipijapa-eclipselink-1.0.1.Final.jar  module.xml
 
Add  eclipselink-2.5.2.jar to module.xml in  modules/system/layers/base/org/eclipse/persistence/main
[oracle@wls1 main]$ cat  module.xml
<module xmlns="urn:jboss:module:1.3" name="org.eclipse.persistence">
    <resources>
        <resource-root path="jipijapa-eclipselink-1.0.1.Final.jar"/>
        <resource-root path="eclipselink-2.5.2.jar"/>
    </resources>
    <dependencies>
        <module name="asm.asm"/>
        <module name="javax.api"/>
        <module name="javax.annotation.api"/>
        <module name="javax.enterprise.api"/>
        <module name="javax.persistence.api"/>
        <module name="javax.transaction.api"/>
        <module name="javax.validation.api"/>
        <module name="javax.xml.bind.api"/>
        <module name="org.antlr"/>
        <module name="org.apache.commons.collections"/>
        <module name="org.dom4j"/>
        <module name="org.javassist"/>
        <module name="org.jboss.as.jpa.spi"/>
        <module name="org.jboss.logging"/>
        <module name="org.jboss.vfs"/>
    </dependencies>

Configure  your pom.xml

• Remove the hibernate reference and add the EclipseLink reference
  

As we provided the EclipseLink Jar as a Wildlfly module add : <scope>provided</scope>

        <dependency>
            <groupId>org.eclipse.persistence</groupId>
            <artifactId>eclipselink</artifactId>
            <version>2.5.2</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.eclipse.persistence</groupId>
            <artifactId>org.eclipse.persistence.jpa.modelgen.processor</artifactId>
            <version>2.5.2</version>
            <scope>provided</scope>
        </dependency>

Create a new Netbeans project

Create new Maven project : Maven -> Web Application 
Add JSF support          : Properties -> Add Framework -> JSF 2.2 
Source Package -> New  -> Entity Class from Database 
Add New File -> Persistence -> Entity Class from Database 
-> Select Datasource:
 Host : ract2-scan.grid12c.example.com 
 Port : 1521/banka
 URL  : jdbc:oracle:thin:@ract2-scan.grid12c.example.com:1521/banka

-> Select table : EMP2
Select ; 
x Generate Named Query Annotations for Persistent Fields
x Generate JAXB Annotations
x Create Persistence Unit

Create persistence.xml 
New File -> Persistence -> Create new Persistence Unit 
-> Select Datasource: ..
x Use Java Transaction API


A working persistence.xml sample may look like :

<?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 version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" 
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
  xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
  <persistence-unit name="jpaPU" transaction-type="JTA">
    <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
    <jta-data-source>java:/jboss/datasources/myRacDS</jta-data-source>
    <jar-file>MyFirstRACPU.jar</jar-file>
    <class>com.hhu.wfjpa2el.Emp2</class>
    <class>com.hhu.wfjpa2el.Logemp2</class>
    <exclude-unlisted-classes>true</exclude-unlisted-classes>
    <properties>
      <property name="eclipselink.logging.level" value="FINEST"/>
      <property name="eclipselink.cache.shared.default" value="false"/>
    </properties>
  </persistence-unit>
</persistence>

• JTA is used and the datasoruce name is : java:/jboss/datasources/myRacDS
• org.eclipse.persistence.jpa.PersistenceProvider is the Persistence Provider
• The perstistence Unit name is jpaPU [ this is used by our JAVA code ]

JAVA Code to create a thread safe access to the Entity Manager

•   Persistence.createEntityManagerFactory(“jpaPU“) must match  <persistence-unit name=”jpaPU” transaction-type=”JTA“>
•  <class>com.hhu.wfjpa2el.Logemp2</class>  must match the  Classes we have  created by using Netbeans menu option : Create Entity Class from Database
• For the Entity Manger access we use the “ThreadLocal Pattern”

 

 static 
      {
        emf = Persistence.createEntityManagerFactory("jpaPU");
        threadLocal = new ThreadLocal<EntityManager>();        
      }
    
    
    public static EntityManager getEntityManager() 
      {
        EntityManager em = threadLocal.get();

        if (em == null) 
          {
          // setRunTimeInfo(getRunTimeInfo() + Tools.add_hmtl_pre_tag("Creating Entity Manager ! "  ));
            logger.info("Creating Entity Manager Factory ..." );
            em = emf.createEntityManager();
            // set your flush mode here
            threadLocal.set(em);
          }
        return em;
      }
    
    
    public static void closeEntityManager() 
      {
        EntityManager em = threadLocal.get();
        if (em != null) 
          {
            logger.info("Closing Entity Manager" );
            em.close();
            threadLocal.set(null);
           }
     }
    
Note for each request you have to open and close the Entity Manager 
   ..
   em=getEntityManager();
   ..
   closeEntityManager();
   ..

A more Complete Code fragment

public String addEntity()  
      {
        EntityManager em;
        String methodName = "addEntity()";
        short eno= getEmpno();
        cleanall();
        try
          {    
            setRunTimeInfo("Calling "  + methodName + "in progress - ID: " + eno + " - useJoinTransaction : " + isUseJoinTransaction() );          
            Emp2 e =  new Emp2(eno);
            e.setEname("Helmut");
            e.setJob("Progr.");
            e.setSal(new BigDecimal(1000.0));
            setRunTimeInfo("Requesting Entity Manager.. ");
            em=getEntityManager();
            ut.begin();
            em.joinTransaction();
            setRunTimeInfo("Running em.persists() ... ");           
            em.persist(e);
            setRunTimeInfo("Running em.flush() ... ");
            em.flush();
            setRunTimeInfo("Running ut.commit() ... ");
            ut.commit();
            setRunTimeInfo("Closing  Entity Manager.. !");
            setRunTimeInfo("Leaving " + methodName + " without Exceptions !");                   
            }            
          catch ( Throwable t1)
          {            
            jpa_exception(t1, methodName);
          }            
        closeEntityManager();
        setRunTimeInfo("Leaving "  +  methodName + " - Entity manager  closed !\n");
        return "index";
      }

The related Server.log File shoud look like :

2015-05-20 18:38:23,361 INFO  [org.eclipse.persistence] (default task-5) EclipseLink, version: Eclipse Persistence Services - 2.5.2.v20140319-9ad6abd
2015-05-20 18:38:23,496 INFO  [org.eclipse.persistence.connection] (default task-5) connecting(DatabaseLogin(
2015-05-20 18:38:23,497 INFO  [org.eclipse.persistence.connection] (default task-5) Connected: jdbc:oracle:thin:@ract2-scan.grid12c.example.com:1521/banka
2015-05-20 18:38:23,497 INFO  [org.eclipse.persistence.connection] (default task-5) connecting(DatabaseLogin(
2015-05-20 18:38:23,497 INFO  [org.eclipse.persistence.connection] (default task-5) Connected: jdbc:oracle:thin:@ract2-scan.grid12c.example.com:1521/banka
2015-05-20 18:38:23,653 INFO  [org.eclipse.persistence.connection] (default task-5) vfs:/usr/local/wildfly-8.2.0.Final/standalone/deployments/t-1.0.war/WEB-INF/classes/_jpaPU login successful