Clarification of redelivery behavior when have ungraceful exit of a transacted client

  public void onMessage(Message message) {

                try {
                    if (message instanceof TextMessage) {
	
                        TextMessage textMessage = (TextMessage) message;
                        System.out.println("Message:"+((TextMessage) message).getText().toString().toLowerCase());
                        //System.exit(1);
                        if (((TextMessage) message).getText().toString().toLowerCase().contains("HELLO".toLowerCase()))
                        {
                        	System.out.println("Yes");
                        	message.acknowledge();
                        	System.exit(1);
                        	session.close();
                        	session.commit();
                        }