Description Michael OBrien 2008-09-09 15:28:27 EDT

This wiki enhancement request surrounds usage of the javax.persistence.jtaDataSource as an override for application scoped datasources deployed with the EAR.
The original wls server bug# 246126 is for WebLogic 10.3 but the behaviour of this persistence unit property should be documented for all application servers.

Issue:
   The jta-data-source is always overriden by the datasource in javax.persistence.jtaDataSource - A documentation wiki is required on usage of this alternate property.
   Current behavior is that javax.persistence.jtaDataSource and nonJtaDataSource (if present) take precedence over the normal <jta-data-source> element.

Example persistence.xml
<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="unified" transaction-type="JTA">
         <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
         <jta-data-source>localOracle10RemoteDS</jta-data-source>
              <properties>
--->              <property name="javax.persistence.jtaDataSource" value="java:app/jdbc/appDS"/>

--------------code references-----------------
This one found by Doug and Shaun during debugging of the workaround for bug# 246126 During a CRUD operation against the entityManager.

1) By design in EntityManagerSetupImpl.getDatasourceFromProperties() we only use the datasource from <jta-data-source> if it is non-null in the supplied PersistenceUnitInfoImpl.

The global datasource "oracle10RemoteDS" defined in <jta-data-source> is ignored, the application managed datasource localOracle10RemoteDS defined in javax.persistence.jtaDataSource is used intead
ignored ---> weblogic.jdbc.common.internal.RmiDataSource@18a24e9
used ---> datasource	"java:app/jdbc/localOracle10RemoteDS" (id=11049)	


    protected javax.sql.DataSource getDatasourceFromProperties(Map m, String property, javax.sql.DataSource defaultDataSource){
        Object datasource = getConfigPropertyLogDebug(property, m, session);
        if ( datasource == null ){
            return defaultDataSource;
        } 
        if ( datasource instanceof String){
            // Create a dummy DataSource that will throw an exception on access
-->         return new DataSourceImpl((String)datasource, null, null, null);

Daemon Thread [[ACTIVE] ExecuteThread: '14' for queue: 'weblogic.kernel.Default (self-tuning)'] (Suspended)	
	EntityManagerSetupImpl.getDatasourceFromProperties(Map, String, DataSource) line: 1035	
	EntityManagerSetupImpl.updateLogins(Map) line: 966	
	EntityManagerSetupImpl.updateServerSession(Map, ClassLoader) line: 1176	
	EntityManagerSetupImpl.deploy(ClassLoader, Map) line: 237	
	EntityManagerFactoryImpl.getServerSession() line: 69	
	EntityManagerFactoryImpl.createEntityManagerImpl(Map, boolean) line: 118


jtaDataSource	RmiDataSource  (id=10956)	
	appName	null	
	classLoader	null	
	driverClass	"weblogic.jdbc.jta.DataSource" (id=11038)	
	driverInstance	DataSource  (id=11039)	
	driverProps	ConcurrentProperties  (id=11040)	
	driverUrl	"jdbc:weblogic:jta:oracle10RemoteDS" (id=11041)	
	isLoggingResource	false	
	jdbcCtx	WLEventContextImpl  (id=11042)	
	jndiNames	String[1]  (id=11043)	
	jtaRegistrationName	"oracle10RemoteDS" (id=11044)	
	moduleName	null	
	pa	null	
	poolName	"oracle10RemoteDS" (id=11044)	
	rmiSettings	RmiDriverSettings  (id=11045)	
	scope	"Global" (id=11046)	
	txDataSource	true	
	useDriver	true	
	verbose	false	


2) Later on in updateLogins() we create our own wrapper for the ds name and dataSource
org.eclipse.persistence.internal.jpa.jdbc.DataSourceImpl@1ca62e2

When we return to the login() call later in deploy() we resolve the datasource and set it on our wrapper - this is the one we use.

Daemon Thread [[ACTIVE] ExecuteThread: '0' for queue: 'weblogic.kernel.Default (self-tuning)'] (Suspended (breakpoint at line 102 in JNDIConnector))	
	JNDIConnector.connect(Properties) line: 118	
	JNDIConnector.connect(Properties, Session) line: 94	
	DatabaseLogin(DatasourceLogin).connectToDatasource(Accessor, Session) line: 164	
	ServerSession(DatabaseSessionImpl).loginAndDetectDatasource() line: 570	
	EntityManagerFactoryProvider.login(ServerSession, Map) line: 209	
	EntityManagerSetupImpl.deploy(ClassLoader, Map) line: 246	
	EntityManagerFactoryImpl.getServerSession() line: 69	
	EntityManagerFactoryImpl.createEntityManagerImpl(Map, boolean) line: 118	


dataSource	RmiDataSource  (id=11046)	
	appName	null	
	classLoader	null	
	driverClass	"weblogic.jdbc.jta.DataSource" (id=10944)	
	driverInstance	DataSource  (id=11047)	
	driverProps	ConcurrentProperties  (id=11048)	
	driverUrl	"jdbc:weblogic:jta:localOracle10RemoteDS" (id=11049)	
	isLoggingResource	false	
	jdbcCtx	WLEventContextImpl  (id=11050)	
	jndiNames	String[1]  (id=11051)	
	jtaRegistrationName	"_appsdir_weblogicEAR88_ear@localOracle10RemoteDS@localOracle10RemoteDS" (id=11052)	
	moduleName	null	
	pa	null	
	poolName	"localOracle10RemoteDS" (id=11053)	
	rmiSettings	null	
	scope	"Application" (id=11054)	
	txDataSource	true	
	useDriver	true	
	verbose	false	


3) We may need to adjust the comments/javadoc for updateLogins() as they contradict each other in their use of the supplied PersistenceUnitInfo.
We should state that if "persistenceInfo is available and valid..."
and that "properties will overrided settings in persistenceUnitInfo"

   /**
     * Override the default login creation method.
     * If persistenceInfo is available, use the information from it to setup the login
     * and possibly to set readConnectionPool.
     */
    protected void updateLogins(Map m){
        DatasourceLogin login = session.getLogin();
    
        // Note: This call does not checked the stored persistenceUnitInfo or extended properties because
        // the map passed into this method should represent the full set of properties we expect to process