Comments on: Spring, JPA, and JTA with Hibernate and JOTM

by: Chris

Mon, 22 Feb 2010 19:08:51 +0000

Couldn't get this working properly. All the time I ended up with either Statements being committed individually via autocommit or not at all or XAExceptions. Then I tried Atomikos essentials transactionmanager together with their datasource (nonjta version). I got that working all right. Just the other day I found a much easier solution to this:Spring's TransactionAwareDataSourceProxy class. The problem all the time was that the datasource was not properly transaction aware (like it is in a jee environment). Just wrap your datasource with TransactionAwareDataSourceProxy and pass it to the LocalContainerEntityManagerFactory via the dataSource property:

<bean id="dataSource" class="org.springframework.jdbc.datasource.TransactionAwareDataSourceProxy"><constructor -arg ref="dbcpDataSource" /> </bean><bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"><property name="dataSource" ref="dataSource"/>.......

No need to enrich the PersistenceUnitInfo or use jndi at allcheers

by: Harpritt

Fri, 06 Nov 2009 23:04:16 +0000

Cheers for the article Erich.... worked a treat!. Any ideas on Colins duplicate tables ?

by: Alexandre

Sat, 28 Feb 2009 20:27:10 +0000

What a big configuration file! Anybody could try another configuration that works ??!?!?!??

by: Colin Smith

Sun, 04 Jan 2009 14:28:42 +0000

Thanks Erich, after some trial and error I got it working. I defined 2 persistenceUnits in my persistence.xml and pointed each entityManagerFactory to its appropriate persistenceUnit using the "persistenceUnitName" property. The only slightly strange side effect is if I use hibernate's generate ddl option it creates tables in both databases!

by: admin

Thu, 01 Jan 2009 07:36:32 +0000

hi colin, you have to make sure that the EntityManagerFactory beans have unique names, use a prefix similar to the way i did it with the datasource beans to define more than one EntityManagerFactory. i used two EntityManagerFactory beans with different names for my last project and had nor problems.

by: Colin

Tue, 30 Dec 2008 14:57:41 +0000

Hi Erich, thanks a lot for your post. I've been trying to use it as the basis for making my JPA application talk to 2 databases (as you suggest at the end of your post, by adding a EntityManagerFactory for the second XA datasource). It seems that is not allowed, the error I get is...org.springframework.beans.factory.NoSuchBeanDefinitionException: No unique bean of type [javax.persistence.EntityManagerFactory] is defined: expected single bean but found 2 at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.findDefaultEntityManagerFactory(PersistenceAnnotationBeanPostProcessor.java:514) at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.findEntityManagerFactory(PersistenceAnnotationBeanPostProcessor.java:473) at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor$PersistenceElement.resolveEntityManager(PersistenceAnnotationBeanPostProcessor.java:599) at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor$PersistenceElement.getResourceToInject(PersistenceAnnotationBeanPostProcessor.java:570) at org.springframework.beans.factory.annotation.InjectionMetadata$InjectedElement.inject(InjectionMetadata.java:180) at org.springframework.beans.factory.annotation.InjectionMetadata.injectFields(InjectionMetadata.java:105) at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.postProcessAfterInstantiation(PersistenceAnnotationBeanPostProcessor.java:308) ... 51 more

by: admin

Wed, 10 Dec 2008 13:25:14 +0000

hi guillaume, you are right, according to the Javadoc the LocalContainerEntityManagerFactoryBean.setDataSource() property should not be necessary/set. can't remember why i set it, probably cos i wanted the LocalContainerEntityManagerFactoryBean configuration to work both for non-JTA and JTA datasources. it doesn't seem to cause any problems though. regarding JNDI, please also have a look at the XBean variant described at the end of the post. it allows bootstrapping a standalone JNDI registry and keeps the configuration closer to the standard. guess instead of the JtaPersistenceUnitPostProcessor one could also implement a custom PersistenceUnitManager extending the DefaultPersistenceUnitManager and setting it via LocalContainerEntityManagerFactoryBean.setPersistenceUnitManager().

by: Guillaume

Wed, 10 Dec 2008 10:36:36 +0000

Hi Erich, nice post, especially the part of how to configure the JTA datasource via Spring without binding directly to the Jndi context. However I wonder why you set anyway the property datasource in the LocalContainerEntityManagerFactoryBean ? Reading spring documentation, this property is seen - JPA speaking - as a not JTA datasource, so it's conflicting with the configuration of the datasource via the JtaPersistenceUnitPostProcessor .

by: vitor

Fri, 05 Dec 2008 04:47:50 +0000

Hi Erich, nice post!When initially building an application using spring + jpa + hibernate I saw your post and, even though I am not using JTA (I am using JpaTransactionManager), I used some of the configurations shown here.Now I am running some performance tests to check if I am using the right configuration, and what took my attention was the JtaPersistenceUnitPostProcessor described here.Basically I am using two configurations:(1) setting the dataSource inside JtaPersistenceUnitPostProcessor like in this post(2) setting dataSource directly into LocalContainerEntityManagerFactoryBean, and not using JtaPersistenceUnitPostProcessor at all.When using org.springframework.jdbc.datasource.DriverManagerDataSource as a data source, the results for both configuration were quite the same. Both took around 255 seconds to complete.However, when using com.mchange.v2.c3p0.ComboPooledDataSource as a data source, the result were really different.For configuration (1) I got 28 seconds, while in configuration (2) it took 75 seconds.Your configuration is almost 3 times faster than not using JtaPersistenceUnitPostProcessor.I ran these tests many times, and results were always the same.Do you have any idea why the results I got were so different??I am actually asking this to know better the internals of spring transaction management, so that I can better tune my system, and I can find any information about persistenceUnitPostProcessors.Regards,Vitor.

by: quan.le

Fri, 14 Nov 2008 09:45:45 +0000

Thank you very very much, this post is a great help for me.Wish all the best for you