How to use JPA in a worker thread?

I'm using WebLogic 10.3.5.0 with JPA 2.0 and have the following scenario:
- user needs to start a task takes some time to complete;
- this task needs to read and write to DB;
One solution would be to write a worker and use the WorkManager feature to start this from an session EJB.
How should I use JPA from this worker to access the DB in a transactional manner?

You should be able to use it as normal.
Your worker class is probably not injected like your SessionBean, so you would either need to pass the EntityManager, or look it up either through JNDI if container managed, or Persistence if application managed.
For transactions, you either need to use JTA directly if using JTA, or use JPA transactions if using RESOURCE_LOCAL.

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pedron wrote:
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How to use JPA in a worker thread?

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