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This application uses JMS API for your business logic and Java Servlet API for user interfaceis a simple JMS application where in a user sends information to the administrator for updation . As we go through the tutorial we will try to understand the basic of Servlets and JMS.

Start the server and Launch the administrative console.
Under Services. Select JMS Resources.
Under Create a new JMS Resource Group:. Select For ActiveMQ.
On the next screen suggest a Resource Group Name. In our case we are using WebJMS. All other values can be taken as default.
Select Next once done.
Select Add Connection Factory on the next page.
In the drop down box select javax.jms.QueueConnectionFactory. Select Next.
Next give the Connection Factory Name as jms/TestConnectionFactory. Keep default for all other fields. Select Next.
Select Add Destination on the next screen.
Select JMS Destination Type as javax.jms.Queue. Select Next.
Name the Message Destination Name as jms/TestQueue. Select Next.
On the next screen Select Deploy Now. This will deploy the created Plan.
Under JMS resources you can see the newly created connection factory and queue.

Adding producer

...

, consumer abd UI code to the application

Right click on WebJMS project and create a new servlet.
Name the servlet as UserServlet and package as webjms. This is the producer in the application.

Select Next and later Finish.

Add the following code to UserServlet.java

Code Block

title	UserServlet.java
borderStyle	solid

package webjms;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Enumeration;

import javax.annotation.Resource;
import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.JMSException;
import javax.jms.MessageProducer;
import javax.jms.Queue;
import javax.jms.Session;
import javax.jms.TextMessage;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class for Servlet: UserServlet
 *
 */
 public class UserServlet extends javax.servlet.http.HttpServlet implements javax.servlet.Servlet {
	 @Resource(name="jms/TestConnectionFactory")
	 private ConnectionFactory connectionFactory;
	 @Resource(name="jms/TestQueue")
	 private Queue queue;
	 static final long serialVersionUID = 1L;
   
   
    /* (non-Java-doc)
	 * @see javax.servlet.http.HttpServlet#HttpServlet()
	 */
	public UserServlet() {
		super();
	}   	
	
	/* (non-Java-doc)
	 * @see javax.servlet.http.HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		PrintWriter out = response.getWriter();
		if(connectionFactory == null) {
			out.println("Connection Factory lookup has failed");
			return;
		}
		
		if(queue == null) {
			out.println("Queue lookup has failed");
			return;
		}
		
		
		
		Connection connection = null;
		try {
			connection = connectionFactory.createConnection();
			connection.start();
			Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
			MessageProducer producer = session.createProducer(queue);
			TextMessage message = session.createTextMessage();
			Enumeration arr=request.getParameterNames();
			while(arr.hasMoreElements())
			{
				String fields= (String)arr.nextElement();
				String paramname[]=request.getParameterValues(fields);
				for (int i=0; i<paramname.length;i++)
				{	
				String s=null;
				s=fields+":" + paramname[i];
				message.setText(s);
				producer.send(message);
				}
				
			}
			out.println("Your request has been sent to administrator.");
            //Send a non-text control message indicating end of messages.
            producer.send(session.createMessage());
		} catch (JMSException e) {
			e.printStackTrace();
		} finally {
			if(connection != null) {
				try {
					connection.close();
				} catch (JMSException e1) { }
			}
		}
	}
	
	/* (non-Java-doc)
	 * @see javax.servlet.http.HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		doGet(request, response);
	}   	  	    
}

Similarly create a second servlet AdminServlet. This is the consumer in the application.

Add the following code to AdminServlet.java

Code Block

title	AdminServlet.java
borderStyle	solid

package webjms;

import java.io.IOException;
import java.io.PrintWriter;

import javax.annotation.Resource;
import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.Queue;
import javax.jms.Session;
import javax.jms.TextMessage;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class for Servlet: AdminServlet
 *
 */
 public class AdminServlet extends javax.servlet.http.HttpServlet implements javax.servlet.Servlet {
	 @Resource(name="jms/TestConnectionFactory")
		private ConnectionFactory connectionFactory; 
		
		@Resource(name="jms/TestQueue")
		private Queue queue;
		
		/* (non-Java-doc)
		 * @see javax.servlet.http.HttpServlet#HttpServlet()
		 */
		public AdminServlet() {
			super();
		}   	
		
		/* (non-Java-doc)
		 * @see javax.servlet.http.HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
		 */
		protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
			PrintWriter out = response.getWriter();
			if(connectionFactory == null) {
				out.println("Connection Factory lookup has failed");
				return;
			}
			if(queue == null) {
				out.println("Queue lookup has failed");
				return;
			}
			Connection connection = null;
			try {
				connection = connectionFactory.createConnection();
				Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
				MessageConsumer consumer = session.createConsumer(queue);
				connection.start();
				out.println("The following information has been received for updation\n");
				while(true) {
					Message m = consumer.receive(); 
					if (m instanceof TextMessage) {
						TextMessage message = (TextMessage) m;
						out.println(message.getText());
					} else {
						break;
					} 
				}
			} catch (JMSException e) {
				e.printStackTrace();
			} finally {
				if(connection != null) {
					try {
						connection.close();
					} catch (JMSException e1) { }
				}
			}
		}  	
		
		/* (non-Java-doc)
		 * @see javax.servlet.http.HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
		 */
		protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
			doGet(request, response);
		}   	  	    
	}

Right Click on WebContent and create a jsp.
Name the jsp as index.jsp. Select Next.

Select Finish.

Add the following code to index.jsp

Code Block

title	index.jsp
borderStyle	solid

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Sample Web Application accessing JMS Resources</title>
</head>
<body>
<form action="/WebJMS/UserServlet">
<h1>Please enter the updated information</h1>
<table>
<tr>
<td>UserName:</td>
<td><input type="text" name="username" size="30"></td>
</tr>
<tr>
<td>UserID:</td>
<td><input type="text" name="userid" size="30"></td>
</tr>
<tr>
<td>Old Address:</td>
<td><input type="text" name="oldaddress" size="30"></td>
</tr>
<tr>
<td>New Address:</td>
<td><input type="text" name="newaddress" size="30"></td>
<tr>
</table>
<input type="submit" value="Submit">
</form>
</body>
</html>

This will create the skeleton for the servlet and jsp required by the application.producer, consumer and user interface required by the application.

Modifying the deployment plan

Modify the deployment plan as shown below

Code Block

title	geronimo-web.xml
borderStyle	solid


<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://geronimo.apache.org/xml/ns/j2ee/web-1.2" xmlns:nam="http://geronimo.apache.org/xml/ns/naming-1.2" xmlns:sec="http://geronimo.apache.org/xml/ns/security-1.1" xmlns:sys="http://geronimo.apache.org/xml/ns/deployment-1.2">
  <sys:environment>
    <sys:moduleId>
      <sys:groupId>default</sys:groupId>
      <sys:artifactId>WebJMS</sys:artifactId>
      <sys:version>1.0</sys:version>
      <sys:type>car</sys:type>
    </sys:moduleId>
    <sys:dependencies>
            <sys:dependency>
                <sys:groupId>org.apache.geronimo.configs</sys:groupId>
                <sys:artifactId>activemq-ra</sys:artifactId>
                <sys:version>2.1</sys:version>
                <sys:type>car</sys:type>
            </sys:dependency>
        </sys:dependencies>
  </sys:environment>
  <context-root>/WebJMS</context-root>
  <nam:resource-ref>
        <nam:ref-name>jms/TestConnectionFactory</nam:ref-name>
        <nam:pattern>
            <nam:groupId>org.apache.geronimo.configs</nam:groupId>
            <nam:artifactId>activemq-ra</nam:artifactId>
            <nam:version>2.1</nam:version>
            <nam:name>DefaultActiveMQConnectionFactory</nam:name>
        </nam:pattern>
    </nam:resource-ref>
    <nam:resource-env-ref>
        <nam:ref-name>jms/TestQueue</nam:ref-name>
        <nam:pattern>
            <nam:groupId>org.apache.geronimo.configs</nam:groupId>
            <nam:artifactId>activemq-ra</nam:artifactId>
            <nam:version>2.1</nam:version>
            <nam:name>SendReceiveQueue</nam:name>
        </nam:pattern>
    </nam:resource-env-ref>
</web-app>

Child pages

Versions Compared

Old Version 4

New Version 5

Key

Adding producer

, consumer abd UI code to the application

Modifying the deployment plan

Child pages

Page History

Versions Compared

Old Version 4

New Version 5

Key

Adding producer

, consumer abd UI code to the application

Modifying the deployment plan