How do you close the JDBC connection back to the Connection pool?
Just make a call to the close() method on the *Connection* object you had got from the pool. While getting a connection from the pool, the Container implements the java.sql.Connection interface and gives an instance to you. When you invoke close() on this instance once you are done with the Connection object, the Container implemented close() will be called and it'll take care of the rest.
Cheers,
Arvind