code: @Override
  	public final Connection createConnection() throws JMSException
      {
      	String username = getStringProperty(Context.SECURITY_PRINCIPAL,null);
      	String password = getStringProperty(Context.SECURITY_CREDENTIALS,null);
      	
          return createConnection(username,password);
      }
docs: /*
  (non-Javadoc)
  @see javax.jms.ConnectionFactory#createConnection()