Revision as of 15:49, 10 December 2009

Running JPA 2.0 API on WebLogic 10.3

WebLogic 10.3.2.0 ships with the JPA 1.0 specification jar - we would like to run JPA 2.0 API on WebLogic. This document describes the solution to container-managed and application managed deployments and the details in getting their use cases running.

Results Matrix

• The following table summarizes the type of test, server modifications and results

Test Conditions

• - verify JPA 2.0 interface call with implementation shipped in EclipseLink 1.2 = entityManager.getMetamodel()
• - verify JPA 2.0 interface call with implementation only in EclipseLink 2.0 = entityManager.getCriteriaBuilder()

=Results Summary

• Container-managed JPA 2.0 entity managers work with the following modifications and constraints.
  • Add both the javax and eclipselink jars to the top of the server classpath
  • Weaving and the new JPA 2.0 interface changes between EclipseLink 1.2 and 2.0 work
  • persistence.xml 2.0 changes will not pass deployment validation

Problem

• This document details a solution for enabling JPA 2.0 API functionality for various enterprise application use cases involving application managed EntityManagers.
• The page is geared to both end users and internal eclipselink.jpa.test server test implementors.
  • 1) End users of WebLogic 10.3.2.0
    • This involves configuring the server for JPA 1.0 permanently or per-deployment
    • Note: This procedure is for application managed deployments - container managed injection will still default to JPA 1.0 for servers that do not ship with 2.0 out of the box
  • 2) EclipseLink JPA test users on WebLogic 10.3.2.0
    • This involves temporarily configuring the server per-test-deployment

• This page is slated for immediate editing over 20090120-11 to make the conclusions more clear - however we have the following result for container-managed EM's
  • EclipseLink JPA 2.0 code (CriteriaBuilder and weaving work)
    • [EL Example]: enterprise: JPA 2.0 CriteriaBuilder: org.eclipse.persistence.internal.jpa.querydef.CriteriaBuilderImpl@2225ece
  • The EM is a proxy
    • EM: class $Proxy84
  • But, persistence.xml 2.0 tags like <shared-cache-mode>NONE</shared-cache-mode>

will not pass validation on the server Caused By: weblogic.deployment.EnvironmentException: Error loading the persistence descriptor META-INF/persistence.xml from the module org.eclipse.persistence.example.jpa.server.weblogic.enterpriseEJB.jar. See the following stack trace for nested errors: weblogic.descriptor.DescriptorException: VALIDATION PROBLEMS WERE FOUND

 F:\view_w35d\examples\org.eclipse.persistence.example.jpa.server.weblogic.enterpriseEJB\build\classes\META-INF\persistence.xml:19:3:19:3: problem: cvc-attribute.4: The value '2.0' does not equal the fixed value '1.0' of attribute 'version':<F:\view_w35d\examples\org.eclipse.persistence.example.jpa.server.weblogic.enterpriseEJB\build\classes/META-INF/persistence.xml:19:3>
 F:\view_w35d\examples\org.eclipse.persistence.example.jpa.server.weblogic.enterpriseEJB\build\classes\META-INF\persistence.xml:28:11:28:11: problem: cvc-complex-type.2.4a: Expected elements 'class@http://java.sun.com/xml/ns/persistence exclude-unlisted-classes@http://java.sun.com/xml/ns/persistence properties@http://java.sun.com/xml/ns/persistence' instead of 'shared-cache-mode@http://java.sun.com/xml/ns/persistence' here in element persistence-unit@http://java.sun.com/xml/ns/persistence:<F:\view_w35d\examples\org.eclipse.persistence.example.jpa.server.weblogic.enterpriseEJB\build\classes/META-INF/persistence.xml:28:11>

• We want a way for end users to override the JPA 1.0 library shipped with WebLogic Server 10.3.2.0 without modifying the server and affecting other applications.
  • For a single EAR use alternative #3 below.

Problem

• This document details a solution for enabling JPA 2.0 API functionality for various enterprise application use cases involving application managed EntityManagers.
• The page is geared to both end users and internal eclipselink.jpa.test server test implementors.
  • 1) End users of WebLogic 10.3.2.0
    • This involves configuring the server for JPA 1.0 permanently or per-deployment
    • Note: This procedure is for application managed deployments - container managed injection will still default to JPA 1.0 for servers that do not ship with 2.0 out of the box
  • 2) EclipseLink JPA test users on WebLogic 10.3.2.0
    • This involves temporarily configuring the server per-test-deployment

Analysis

• EclipseLink 1.2 and 2.0+ fully implement the JPA 2.0 specification via enhancement # 248291 and are the RI for the GlassFish V3 JEE6 server. In order to use this functionality the 2.0 version of the JPA specification jar - javax.persistence.jar must be added higher in the WebLogic server classpath see enhancement # 296271.
• Now, you may have noticed that the modules/org.eclipse.persistence_1.0.0.0_1-2-0.jar jar contains JPA 2.0 API implementation classes such as org.eclipse.persistence.internal.jpa.metamodel - however this API is not available through interface classes (because only the javax.persistence 1.0 jar is present) and we also are missing the services file for Criteria/Metamodel - in any case a predeploy should fail where the EAR contains JPA 2.0 API out of the box.

Use Cases

• Use case partitioning criteria
  • Application managed EM
    • @PersistenceUnit EMF or static bootstrap Persistence.createEntityManagerFactory EMF
      • Global scoped datasource
        • UC 1 : JTA global scoped datasource - alternative #3
        • UC 2 : non-JTA global scoped datasource
        • UC 3 : RESOURCE_LOCAL jdbc connector
      • Application scoped datasource
        • UC 11 : JTA global scoped datasource
        • UC 12 : non-JTA global scoped datasource
        • UC 13: RESOURCE_LOCAL jdbc connector
  • Container managed EM
    • @PersistenceUnit EMF and/or @PersistenceContext EM injection on session bean
      • Global scoped datasource
        • UC 21 : JTA global scoped datasource
        • UC 22 : non-JTA global scoped datasource
        • UC 23 : RESOURCE_LOCAL jdbc connector - invalid
      • Application scoped datasource
        • UC 31 : JTA global scoped datasource
        • UC 32 : non-JTA global scoped datasource
        • UC 33 : RESOURCE_LOCAL jdbc connector - invalid

Design

Design Issue 1: JSR-317 JPA 2.0 EJB 3.1 Support

DI 1: Problem

• The modules currently shipped with WebLogic 10.3.2.0 (Patch Set 1) in are the following JPA 1.0 compatible versions - these must be overriden in order to run JPA 2.0 API.
  • modules/org.eclipse.persistence_1.0.0.0_1-2-0.jar
  • modules/javax.persistence_1.0.0.0_1-0-2.jar

DI 1: Alternative 1: Manual overwrite of eclipselink and javax.persistence libraries in modules

• Current solution - this should be deprecated.

DI 1: Alternative 2: Reference higher in the server classpath via commEnv.cmd

• Workable solution but it has issues
  • The server now runs a single version of the two libraries for all applications - this may not be compatible with older applications or other JPA providers running on the server.

DI 1: Solution

• In <WEBLOGIC_HOME>\wlserver_10.3\common\bin\commEnv.cmd
  • change
    • set WEBLOGIC_CLASSPATH=%JAVA_HOME%\lib\tools.jar...
  • To
    • set WEBLOGIC_CLASSPATH=F:/view_w35d/jpa/plugins/javax.persistence_2.0.0.*.jar;%JAVA_HOME%\lib\tools.jar...
    • where F:/view_w35d == %SVN_TRUNK
• Note: do not use the javax.persistence_2.0_preview.jar - the dated javax.persistence_2.0.0.*.jar one is the final PFD version for the JPA 2.0 specification.

DI 1: Alternative 3: Application Level Shared Library - In Use

This example uses an aplication-managed EE injected EMF.

• 20091202 working standalone Eclipse EAR (WAR only) prototype attached bug 296271 - this procedure has been verified on 2 separate servers on separate machines (in order to filter out any possible leftover configuration experimentation that could skew results)
• The following artifacts and modifications are required (failure of any one of these will result in a Persistence Unit not found during deployment or runtime)

• 1) Start with an EAR project containing only a WAR (no ejb-jar) - Eclipse can generate one for you after you install the WebLogic Eclipse Plugin
• 2) Ship EclipseLink 2.0 and JPA 2.0 in the EAR project (not the WAR)
  • 2a) Add eclipselink.jar V2 (OSGI version is org.eclipse.persistence_1.0.0.0_2-0-0.jar) to EarContent\APP-INF\lib - this will override org.eclipse.persistence_1.0.0.0_1-2-0.jar in the modules dir on the server
  • 2b) Add the JPA 2.0 specification jar - this will override javax.persistence_1.0.0.0_1-0-2.jar.
• 3) Update the .MANIFEST where the root of the entity classes managed by the EntityManager reside (here the src\META-INF off the WAR) to point to these included jars (relative paths not required if they are in the classpath - which they are)
  • Class-Path: javax.persistence_2.0.0.v200911041116.jar eclipselink.jar
• 4) Place your persistence.xml descriptor as usual for an application-managed entityManager in the WAR also at the classes root in src\META-INF - this will be exported to the server as classes. (Normally for a container-managed entityManager we would place persistence.xml and all entities in the ejb jar)
  • 4a) make sure to modify the Entity package paths as we are dealing with an SE persistence unit here
• 5) Add the prefer-application-packages element to weblogic-application.xml so the internal WebLogic API FilteredClassLoader places our library ahead of the modules directory.

<wls:prefer-application-packages>
  <wls:package-name>javax.persistence.*</wls:package-name>
  <wls:package-name>org.eclipse.persistence.*</wls:package-name>
</wls:prefer-application-packages>

• 6) The EMF is either EE injected or obtained via a static Persistence call

    @PersistenceUnit(unitName="example")
    private EntityManagerFactory emf;
or
    private EntityManagerFactory emf;
    emf  = Persistence.createEntityManagerFactory("example);

• 7) The following configuration elements are not present in this procedure
  • - no web.xml persistence-context-ref
  • - no weblogic-application.xml 'wls:library-ref
  • - no global shared-library EAR on the server either via the console or via the Eclipse IDE.
  • - no overriding javax.persistence or eclipselink.jar in the modules, domain/lib, wlserver_10.3/common/lib or wlserver_10.3/server/lib directories
  • - no scripted override on either wlserver_10.3/common/bin/commEnv.cmd or base_domain/bin/startWebLogic.cmd

• Note: at this time there is no requirement to add WebLogic platform specific handling for the FilteredClassLoader - we are ok with the XML EAR deployment descriptor change.

Output 3

• Note that the entityManager.getMetamodel() JPA 2.0 call in the application is resolved correctly with this fix.

DI 1: Alternative 4: Global Level Shared Library

• 20091202 - in progress
• See WebLogic Help http://localhost:7001/consolehelp/console-help.portal?_nfpb=true&_pageLabel=page&helpId=library.DeployLibrary
• See WebLogic documentation http://download.oracle.com/docs/cd/E12840_01/wls/docs103/programming/classloading.html#wp1097064
• We need to respond to the post about the FilterClassLoader with the procedure on creating a shared library for JPA 2.0 and EclipseLink 2.0 that is above the modules directory on WebLogic classpath.

DI 1: Alternative 5: Domain Extension Template

• 20091202 - This one suggested by Doug - similar to what is done for other vendor libraries.
• This method involves copying the JPA 2.0 libraries to the lib directory off the current domain
  • example: %WEBLOGIC_HOME%\user_projects\domains\base_domain\lib
  • is below
  • %WEBLOGIC_HOME%\modules
• The domain lib override alternative will not work because this lib is below the server classpath and has no effect after 10.3.0.
• Our current weblogic.xml test script copies the xdb, spatial, jdbc, junit, xmlparserv2 and trunk eclipselink.jar to the domain lib - however this only works if no library is in modules that will override these domain libs.

Since 10.3.1 the user still needs to apply a patch to override modules libs in these lib cases. Therefore this option is deprecated for 10.3.1 and 10.3.2 since we started shipping with the eclipselink jar.

• Potential modification to weblogic.xml:weblogic-install is (without $ variable prefix)

  <copy file="F:/view_w35d/jpa/plugins/javax.persistence_2.0.0.v200911041116.jar" todir="${weblogic.domain}/lib"/>

• Another issue to solve is the absence of OSGI functionality - fixed by editing the .MANIFEST - see bug# 296733

<2-Dec-2009 1:09:45 o'clock PM EST> <Notice> <WebLogicServer> <BEA-000395> <Following extensions directory contents added to the end of the classpath:
C:\opt\wls10320\user_projects\domains\base_domain\lib\eclipselink.jar;C:\opt\wls10320\user_projects\domains\base_domain\lib\javax.persistence_2.0.0.v200911041116.jar;F:\view_w35d\jpa\plugins\javax.persistence_2.0.0.v200911041116.jar> 
<2-Dec-2009 1:09:45 o'clock PM EST> <Critical> <WebLogicServer> <BEA-000386> <Server subsystem failed. Reason: 
java.lang.NoClassDefFoundError: org/osgi/framework/BundleActivator
java.lang.NoClassDefFoundError: org/osgi/framework/BundleActivator

DI 1: Alternative 6: Use -Dweblogic.ext.dirs override

• Like alternative #5 - this one is also appended to the end of the server classpath - so is not of use.
• base_domain/bin/startWebLogic.cmd
  • JAVA_OPTIONS=%JAVA_OPTIONS% -Dweblogic.ext.dirs=F:/view_w35d/jpa/plugins/javax.persistence_2.0.0.v*.jar

Implementation

Application Managed Clients

• The shared-library approach has been prototyped as Alternative #3 and functions fine for EARs that utilize application managed entitymanagers - the Eclipse 1.2 and JPA 1.0 libraries shipped with WebLogic 10.3.2.0 are overriden by the supplied EclipseLink 2.0 and JPA 2.0 libraries in the EAR.
• See the development bug #296271 for attached EAR test archives.

Container Managed Clients

• Support for container managed applications is as-is with out of the box JPA 1.0 API functionality - however the alternatives above give WebLogic server administratiors options for setting the JPA 2.0 specification library ahead of the shipped 1.0 jar in the server classpath.

Log

• 20091201: Start investigation
• 20091202: Scope of this issue has been reduced to the application managed EAR level - @PersistenceContext injection of a 2.0 EM is not supported for EE servers that do not support JPA 2.0 out of the box.
  • The example used for EAR testing uses a container-managed EM via the following injected bean - this will be modified

@Local @Stateless
public class ApplicationService implements ApplicationServiceLocal {
	@PersistenceContext(unitName="example", type=PersistenceContextType.TRANSACTION)	
	private EntityManager entityManager;

Resources

• 249213
• 296271
• 296717
• 296727
• 296220
• 296233