jmssnmpreplier.java

this is example use EJB with jboss.

/*
 * Copyright(C) 2008, NTT AT Co., Ltd.
 * Project: AWGView
 *
 * Notes:
 *  N/A
 *
 * Record of change:
 * Date         Version      Name       Content
 * 2008/12/15   1.0          TriNT      First create       
 */
package jp.co.ntt.awgview.server.jms;

import javax.jms.Destination;
import javax.jms.ExceptionListener;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.MessageListener;
import javax.jms.MessageProducer;
import javax.jms.ObjectMessage;
import javax.jms.QueueConnection;
import javax.jms.Session;
import javax.naming.NamingException;

import jp.co.ntt.awgview.server.AppMainServer;
import jp.co.ntt.awgview.server.common.LogWriter;
import jp.co.ntt.awgview.server.common.Utils;
import jp.co.ntt.awgview.server.constant.Constants;
import jp.co.ntt.awgview.server.thread.AgentDispatcher;
import jp.co.ntt.awgview.server.vo.SnmpVO;

/**
 * Class name : JmsSnmpReplier <BR>
 * 
 * Package : jp.co.ntt_at.awgview.server.jms <BR>
 * 
 * Description : A Message Endpoint that waits to receive the request message;
 * when it does, it responds by sending the reply message.<BR>
 * The Queue the Replier uses to send the reply message to the Requestor. <BR>
 * Implement the javax.jms.MessageListener interface, which includes an
 * onMessage() method. <BR>
 * 
 * @author : AI&T
 * @version : 1.0
 */
public class JmsSnmpReplier implements MessageListener {

	private Session session;
	private QueueConnection connection;
	private boolean transacted = false;
	private static String queueName = "Unkown";
	
		
	protected JmsSnmpReplier() {
		super();
	}

	/**
	 * New Replier Object
	 * 
	 * @param requestQueueName
	 *            : The Queue uses to send the reply message to the Requestor.
	 * @return JmsSnmpReplier
	 * @throws JMSException
	 * @throws NamingException
	 */
	public static JmsSnmpReplier newReplier(String requestQueueName)
			throws JMSException, NamingException {
		try {
			queueName = requestQueueName;
			JmsSnmpReplier replier = new JmsSnmpReplier();
			replier.initialize(requestQueueName);			
			return replier;
		} catch (JMSException e) {
			LogWriter.getSNMPLogger().error("Can not initialize Jms");
			LogWriter.getSNMPLogger().error("Ability to JBoss server has not run " +
					"\n\tor Queue [" + requestQueueName +"] does not exist on the JBoss server" +
					"\n\tor other awgview server is running. " +
					"\n\tPls check again or contact with admin");
			LogWriter.getSNMPLogger().error("Exception occurred: " + e.toString());
			throw e;
		} catch (NamingException e) {
			LogWriter.getSNMPLogger().error("Can not initialize Jms");
			LogWriter.getSNMPLogger().error("Ability to JBoss server has not run " +
					"\n\tor Queue [" + requestQueueName +"] does not exist on the JBoss server" +
					"\n\tor other awgview server is running. " +
					"\n\tPls check again or contact with admin");
			LogWriter.getSNMPLogger().error("Exception occurred: " + e.toString());
			
			if(LogWriter.getSNMPLogger().isTraceEnabled()){
				LogWriter.getSNMPLogger().trace(Utils.parseException(e));
			}
			
			throw e;
		}
	}

	/**
	 * JmsSnmpReplier initialize: - Create all the necessary objects for sending
	 * messages to a JMS queue. - Set the message listener using the following
	 * MessageConsumer method, passing the listener information
	 * 
	 * @param requestQueueName
	 *            : The Queue uses to send the reply message to the Requestor.
	 * @throws NamingException
	 * @throws JMSException
	 */
	protected void initialize(String requestQueueName) throws NamingException,
			JMSException {
		try {
			// Look up a connection factory in JNDI.
			connection = JndiUtils.getQueueConnection();
			session = connection.createSession(transacted, Session.AUTO_ACKNOWLEDGE);
			connection.setExceptionListener(new ExceptionListener(){
                public void onException(JMSException arg0) {
                    LogWriter.getSNMPLogger().error("Exception code " + arg0.getErrorCode() + 
                            " message = " + arg0.getMessage());
                    if(LogWriter.getSNMPLogger().isDebugEnabled()){
                        LogWriter.getSNMPLogger().debug(Utils.parseException(arg0));
                    }
                    LogWriter.getSNMPLogger().fatal("JBoss Server interrupted!");
                    // AppMainServer.shutDown();
                    System.exit(Constants.SYSTEM_EXIT);
                }			    
			});

			Destination requestQueue = JndiUtils
					.getDestination(requestQueueName);

			MessageConsumer requestConsumer = session
					.createConsumer(requestQueue);
			MessageListener listener = this;
			requestConsumer.setMessageListener(listener);
			connection.start();
		} catch (JMSException e) {
			LogWriter.getSNMPLogger().error("Can not Snmp Replier initialize");
			LogWriter.getSNMPLogger().error("Exception occurred: " + e.toString());
			doDisconnect();
			
			if(LogWriter.getSNMPLogger().isTraceEnabled()){
				LogWriter.getSNMPLogger().trace(Utils.parseException(e));
			}
			
			throw e;
		}
	}

	/**
	 * JmsSnmpReplier implement the javax.jms.MessageListener interface, which
	 * includes an onMessage() method. <BR>
	 * 
	 */
	public synchronized void onMessage(Message message) {
		try {
			
			if (message instanceof ObjectMessage) {
				ObjectMessage requestOjbMessage = (ObjectMessage) message;
				
				if (requestOjbMessage.getObject() instanceof SnmpVO) {					
					try {
						SnmpVO snmpVO = (SnmpVO) requestOjbMessage.getObject();
						if (snmpVO != null) {
							if (AppMainServer.agentDispatcher == null){
								AppMainServer.agentDispatcher = new AgentDispatcher(); 
							}
							AppMainServer.agentDispatcher.handleOnSnmpCommand(this, message, snmpVO);
						}
					} catch (Exception e) {
						e.printStackTrace();
						LogWriter.getSNMPLogger().debug(e.toString());
					}
				}
			}
		} catch (JMSException e) {
			LogWriter.getSNMPLogger().error(e.toString());
			
			if(LogWriter.getSNMPLogger().isTraceEnabled()){
				LogWriter.getSNMPLogger().trace(Utils.parseException(e));
			}
			e.printStackTrace();
		}
	}
	
	/***
	 * Receive the request message; when it does, it responds by sending the reply message.
	 * 
	 * @param message
	 * @param updateSnmpVO
	 * @return boolean
	 */
	public boolean replyToClient(Message message, SnmpVO updateSnmpVO) throws NamingException, JMSException {
		try {
			if (message instanceof ObjectMessage) {
				ObjectMessage requestOjbMessage = (ObjectMessage) message;				
				Destination replyDestination = message.getJMSReplyTo();
	
				if (replyDestination != null) {
					
					if (connection == null){
						initialize(queueName);
					}
					
					MessageProducer replyProducer = session.createProducer(replyDestination);				
					// Create object to send
					ObjectMessageCreator msgCreator = new ObjectMessageCreator();
					Message objMessage = msgCreator.createObjectMessage(session,
							updateSnmpVO, requestOjbMessage.getJMSMessageID());				
	
					if (objMessage != null) {
						replyProducer.send(objMessage);
						//LogWriter.getSNMPLogger().info("Data send to client: " + updateSnmpVO.toString());
						if (transacted) {
							session.commit();
							LogWriter.getSNMPLogger().debug("Finished commiting the session.");
						}
						return true;
					} else {
						LogWriter.getSNMPLogger().info("Data send to client: " + updateSnmpVO.toString());
						LogWriter.getSNMPLogger().error("Cannot create Object Message. Server send to client: Failed.");					
						return false;
					}
				} else {
					LogWriter.getSNMPLogger().error("replyDestination is null || message.getJMSReplyTo() is null. " +
							"Server send to client: False");
					return false;
				}
			}
			return false;
		} catch (Exception e) {
			LogWriter.getSNMPLogger().error(e.toString());
			
			if(LogWriter.getSNMPLogger().isTraceEnabled()){
				LogWriter.getSNMPLogger().trace(Utils.parseException(e));
			}
			return false;
		}
	}

	/*
	 * Destroy/close session and connection.
	 */
	public void doDisconnect() throws JMSException{
		try {
			// Close session
			if (session != null) {
				session.close();
			}

			// Close Connection
			if (connection != null) {
				connection.close();
			}			
			session = null;
			connection = null;
			super.finalize();			
		} catch (JMSException e) {
			LogWriter.getSNMPLogger().error(e.toString());			
			if(LogWriter.getSNMPLogger().isTraceEnabled()){
				LogWriter.getSNMPLogger().trace(Utils.parseException(e));
			}
		} catch (Exception e) {
			LogWriter.getSNMPLogger().error(e.toString());			
			if(LogWriter.getSNMPLogger().isTraceEnabled()){
				LogWriter.getSNMPLogger().trace(Utils.parseException(e));
			}
		} catch (Throwable e) {
			LogWriter.getSNMPLogger().error(e.toString());			
			if(LogWriter.getSNMPLogger().isTraceEnabled()){
				LogWriter.getSNMPLogger().trace(Utils.parseException(e));
			}
		}
	}
}