How do I connect to multiple databases using JPA Glassfish Java EE?

Question

I have an application using JSF,EJB,JPA, Glassfish. There are multiple(may be around thousand or more) clients using my app, however each client has a separate database. All the databases have the same schema. I would like to determine which database connection to use at the time when a user logs into the system.

For example client A enters client code, username, and password and logs in, I determine that client A belongs to database A, grab the connection for database A and continue on my merry way.

I am using JPA as my persistence provider. Is it possible to set datasource in persistence.xml at runtime? Is there .java version of persistence.xml available? Is there a better/preferred way to do this? PersistenceUnit name will be same for all the connections.

Thanks

Answer 1

If you know all users in advance then you can create separate persistence unit for every user in persistence.xml and use factory for select Persistence Unit Name for users. Addition of users, require modification in persistence.xml and redeployment of Application.