newbie question - servlets and JMS
Hi Guys
Im trying to write a servlet that receives a File and then sends it using JMS.... i have some basic code in place (from examples ive fouond) ...
Ive written 2 classes
1) a servlet that receives the file
2) a requester that sends the data to the JMS Queue
But there is a couple of things im not sure of ( see code below)....
1) How do i instantiate the 'connection' that im passing into the newRequester method of the JMSRequester class?
2) What sort of strings do i pass into newRequester for the other params?
3) Is it ok to place a FILE object as a parameter of the textMessage.setObjectProperty call?
4) Is my solution ok? Am i on track or am I way off the mark?
5) What JAR do i need for the JndiUtil class?
Thanks for any help
Marty
package lmc.servlet;
import lmc.servlet.JMSRequester;
import java.io.File;
import java.io.IOException;
import java.util.List;
import javax.jms.Connection;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;
publicclass PATFServletextends HttpServlet{
private Logger logger = Logger.getLogger(PATFServlet.class.getName());
publicstaticvoid main(String[] args){
// TODO Auto-generated method stub
}
publicvoid doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException{
String filename = request.getParameter("Filename");
File patfDetail = (File) request.getAttribute("PATFDetail");
Connection connection =null;
String requestQueueName ="abc";
String replyQueueName ="abc";
String invalidQueueName ="abc";
try{
JMSRequester jmsRequest = JMSRequester.newRequester(connection, requestQueueName,
replyQueueName,
invalidQueueName);
jmsRequest.send(patfDetail, filename);
}catch (Exception e){
}
}
}
====================================
package lmc.servlet;
import java.io.File;
import javax.jms.Connection;
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.MessageProducer;
import javax.jms.Session;
import javax.jms.TextMessage;
import javax.naming.NamingException;
publicclass JMSRequester{
private Session session;
private Destination replyDestinationQueue;
private MessageProducer requestMessageProducer;
private MessageConsumer replyMessageConsumer;
private MessageProducer invalidMessageProducer;
/*
* Default Constructor
*/
protected JMSRequester(){
super();
}
/*
* Static method that creates an instance of the JMSRequester class
* and
*/
publicstatic JMSRequester newRequester(Connection connection,
String requestQueueName,
String replyQueueName,
String invalidQueueName)
throws JMSException, NamingException{
JMSRequester jmsRequestor =new JMSRequester();
jmsRequestor.initialise(connection, requestQueueName,
replyQueueName, invalidQueueName);
return jmsRequestor;
}
/*
* In initialize, the requestor uses the Connection and queue names to
* connect to the messaging system.
*/
protectedvoid initialise(Connection connection,
String requestQueueName,
String replyQueueName,
String invalidQueueName)
throws NamingException, JMSException{
session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
Destination requestQueue = JndiUtil.getDestination(requestQueueName);
Destination invalidQueue = JndiUtil.getDestination(invalidQueueName);
replyDestinationQueue = JndiUtil.getDestination(replyQueueName);
requestMessageProducer = session.createProducer(requestQueue);
invalidMessageProducer = session.createProducer(invalidQueue);
replyMessageConsumer= session.createConsumer(replyDestinationQueue);
}
/*
* This method sends the object to the JMS Queue.
*/
publicvoid send(File patfDetail, String patfFilename)throws JMSException{
TextMessage textMessage = session.createTextMessage();
textMessage.setText("Hello world.");
textMessage.setJMSReplyTo(replyDestinationQueue);
textMessage.setObjectProperty(patfFilename, patfDetail);
requestMessageProducer.send(textMessage);
//print out details of the message
System.out.println("Sent request");
System.out.println("\tTime:" + System.currentTimeMillis() +" ms");
System.out.println("\tMessage ID: " + textMessage.getJMSMessageID());
System.out.println("\tCorrel. ID: " + textMessage.getJMSCorrelationID());
System.out.println("\tReply to:" + textMessage.getJMSReplyTo());
System.out.println("\tContents:" + textMessage.getText());
}
/*
* This method allows the class to receive reply messages.
*/
publicvoid receiveSync()throws JMSException{
Message msg = replyMessageConsumer.receive();
if (msginstanceof TextMessage){
TextMessage replyMessage = (TextMessage) msg;
System.out.println("Received reply ");
System.out.println("\tTime:" + System.currentTimeMillis() +" ms");
System.out.println("\tMessage ID: " + replyMessage.getJMSMessageID());
System.out.println("\tCorrel. ID: " + replyMessage.getJMSCorrelationID());
System.out.println("\tReply to:" + replyMessage.getJMSReplyTo());
System.out.println("\tContents:" + replyMessage.getText());
}else{
System.out.println("Invalid message detected");
System.out.println("\tType:" + msg.getClass().getName());
System.out.println("\tTime:" + System.currentTimeMillis() +" ms");
System.out.println("\tMessage ID: " + msg.getJMSMessageID());
System.out.println("\tCorrel. ID: " + msg.getJMSCorrelationID());
System.out.println("\tReply to:" + msg.getJMSReplyTo());
//resend the message...
msg.setJMSCorrelationID(msg.getJMSMessageID());
invalidMessageProducer.send(msg);
}
}
}
