Initializes three properties INITIAL_CONTEXT_FACTORY, PROVIDER_URL,
and OBJECT_FACTORIES and retrieves
a ConnectionPoolDataSource object.
For a more complete code example, see sample2/SimpleConnectionPool.java. The
fundamental difference between access by client and middle-tier client is:
...
ConnectionPoolDatabase cpds = (ConnectionPoolDataSource)
ctx.lookup("servername=myASE");
PooledConnection pconn = cpds.getPooledConnection();