Salient Soft

I’ve found that this is useful for prototyping/mockups of apps that are targetted for GlassFish. It is possible to run JPA with Eclipselink outside an EJB container, so a JSF/JPA app can be run under Tomcat, resulting in less overhead and faster turnaround of changes. For a while I’ve had to use a PC which is RAM limited, and so developing/prototyping with Eclipse and Glassfish has been slow. Turning around deployments/changes around takes time, and I’ve found the synchronisation between Eclipse and Glassfish to be a bit fussy – sometimes Eclipse misunderstands the state of Glassfish, needing a Glassfish restart which again takes valuable time.

Note the following points on doing this:-

1/ My application stack looks similar to the ‘real’ one, but my Service layer/domain objects are just POJOs which are explicitly created or injected via faces_config.xml. This Oracle Example details the various IOC features of the JSF. managed bean facility.

2/ Persistence.xml needs setting up differently to run JPA outside the container. I have found it easiest to specify the database connection explicitly, rather than using a data source. In Eclipse, you can use the persistence.xml editor to populate the connection properties directly from the one Eclipse uses for its entity validation. Whilst you can do JNDI lookups of a data source stored in Tomcat, the naming context used is different, as it makes use of the Enterprise Naming Context (ENC), i.e. “java:comp/env”. This example details how to do it if you want to go that way. A sample persistence.xml follows (with entries commented out where they have been replaced for use with Tomcat) :- 

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="1.0" 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_1_0.xsd">

 <!--<persistence-unit name="SentryPrototype" transaction-type="JTA">-->
 <persistence-unit name="SentryPrototype" transaction-type="RESOURCE_LOCAL">

   <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>

   <!--<jta-data-source>jdbc/JPATestPool</jta-data-source>-->

   <class>uk.co.salientsoft.jpatest.domain.UserInfo</class>
   <properties>
    <property name="eclipselink.logging.level" value="INFO" />

    <!-- <property name="eclipselink.target-server" value="SunAS9" />-->
    <property name="eclipselink.target-server" value="None" />

    <property name="eclipselink.session-name" value="SentryPrototypeSession" />
    <property name="eclipselink.target-database" value="Oracle" />   
    <property name="eclipselink.ddl-generation.output-mode" value="database" />

    <property name="eclipselink.jdbc.url" value="jdbc:oracle:thin:@localhost:1521:xe"/>
    <property name="eclipselink.jdbc.user" value="sentry"/>
    <property name="eclipselink.jdbc.password" value="sentry"/>
    <property name="eclipselink.jdbc.driver" value="oracle.jdbc.OracleDriver"/>

   </properties>
  </persistence-unit>
</persistence>

3/ Ref this eclipse tutorial :-
Tomcat does not have an EJB container so you must add EJB 3.0/JPA 1.0 capability for EclipseLink JPA by placing the specification persistence.jar into the container lib directory $TOMCAT_HOME/lib.
It is recommended to put persistence_1_0.xsd there as well.  It is not recommended that the WAR include its own version of persistence.jar. Your eclipse project should reference but not include this jar and xsd.

The eclipselink.jar should be placed off of the container lib directory $TOMCAT_HOME/lib.
Since Tomcat does not include an EJB container, you may put eclipselink.jar in the web applications’s lib directory or higher up in the classloader by putting it off of Tomcats’ lib directory, where all web applications can access it.
Do not split the eclipselink.jar from the javax.persistence jar – keep them together – preferably in $TOMCAT_HOME/lib

 4/ Tomcat has its own dependencies on the Expression Language (EL) web libraries. These should be removed from WEB_INF/lib when deploying to Tomcat as pointed out here. (If you do not do this, the application will crash with duplicate class loading exceptions.) This may be done in eclipse on the Java Server Faces facet page – open the project properties for the project, and select Java Server Faces under Project Facets. Untick the entry for Standardized EL Library v1.0.

Then save the changes and redeploy the application.

For more information, the eclipse tutorial referenced in 3/ goes into greater depth on the subject. You can also find a list of the available eclipse JPA tutorials here.

5/ When running xxxxxx

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