In Netbeans in the persistence.xml there is a checkbox called "Use Java Transaction API" this changes the xml from:
<persistence-unit name="PUNAME-PU" transaction-type="RESOURCE_LOCAL">
To:
<persistence-unit name="PUNAME-PU" transaction-type="JTA">
Is this for CMT vs BMT?
Here's what the JPA2 specification says about this attribute:
The transaction-type attribute is used to specify whether the entity managers provided by the entity manager factory for the persistence unit must be JTA entity managers or resource-local entity managers. The value of this element is JTA or RESOURCE_LOCAL. A transaction-type of JTA assumes that a JTA data source will be provided—either as specified by the jta-data-source element or provided by the container. In general, in Java EE environments, a transaction-type of RESOURCE_LOCAL assumes that a non-JTA datasource will be provided. In a Java EE environment, if this element is not specified, the default is JTA. In a Java SE environment, if this element is not specified, the default is RESOURCE_LOCAL.
And here is what it says about JTA and resource local entity managers:
JTA EntityManagers
An entity manager whose transactions are controlled through JTA is a JTA entity manager. A JTA entity manager participates in the current JTA transaction, which is begun and committed external to the entity manager and propagated to the underlying resource manager.
Resource-local EntityManagers
An entity manager whose transactions are controlled by the application through the EntityTransaction API is a resource-local entity manager. A resource-local entity manager transaction is mapped to a resource transaction over the resource by the persistence provider. Resource-local entity managers may use server or local resources to connect to the database and are unaware of the presence of JTA transactions that may or may not be active.
