No Persistence provider for EntityManager named

Question

I have my persistence.xml with the same name using TopLink under the META-INF directory. Then, I have my code calling it with:

Answer 1

The question has been answered already, but just wanted to post a tip that was holding me up. This exception was being thrown after previous errors. I was getting this:

property toplink.platform.class.name is deprecated, property toplink.target-database should be used instead.

Even though I had changed the persistence.xml to include the new property name:

Following the message about the deprecated property name I was getting the same PersistenceException like above and a whole other string of exceptions. My tip: make sure to check the beginning of the exception sausage.

There seems to be a bug in Glassfish v2.1.1 where redeploys or undeploys and deploys are not updating the persistence.xml, which is being cached somewhere. I had to restart the server and then it worked.