From a discussion with Patrick on the dev mailing list...
Me: According to the JPA spec, we can define multiple persistence-units in a single persistence.xml file. But, when I try to use this persistence.xml file as input to the PCEnhancer, it is only processing the first persistence-unit that is defined. I traced through the code and found that this is the case. When the persistence.xml file is processed, a "null" name is passed in for the desired persistence-unit (in the ConfigurationProviderImpl.load method) and, thus, only the first one defined is returned and used by the PCEnhancer.
Patrick: IMO, the correct behavior should be:
- PCEnhancer run with no arguments should load all the PUs in the
classpath, find the OpenJPA (or unspecified) PUs, and run against all
the classes defined by those PUs (including auto-scanning for PUs so
- The developer should not need to specify META-INF/persistence.xml when
invoking the PCEnhancer.
- We may want to provide a means to specify specific PUs to process. For
java ...PCEnhancer -p META-INF/persistence.xml#foo
or maybe just
java ...PCEnhancer -p #foo
Regardless, the current behavior seems wrong, and it seems that the best
initial change would be to make PCEnhancer load all the PUs (the first
bullet above), which means manually loading the META-INF/persistence.xml
resources and finding the ones that are OpenJPA PUs, rather than relying
on the javax.persistence.Persistence helper method to load them.
Writing this bug report so as not to lose track of this problem.