SimpleServlet

EchoServlet.java

package org.magnum.mobilecloud.servlet;

import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * An example of a very simple servlet that looks for a single request
 * parameter and echos the parameter value back to the client using
 * the "text/plain" content type.
 * 
 * @author jules
 *
 */
public class EchoServlet extends HttpServlet // Servlets should inherit from HttpServlet
{

	/**
	 * All HTTP GET requests that are routed to the servlet are handled by
	 * this method. All of the routing information about which requests
	 * should be sent to this servlet are handled in the web.xml file
	 * (see: src/main/webapp/WEB-INF/web.xml)
	 * 
	 */
	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		
		// Set the content type header that is going to be returned in the
		// HTTP response so that the client will know how to display the
		// result.
		resp.setContentType("text/plain");
		
		// Look inside of the HTTP request for either a query parameter or
		// a url encoded form parameter in the body that is named "msg"
		String msg = req.getParameter("msg");
		
		// http://foo.bar?msg=asdf
		
		// Echo a response back to the client with the msg that was sent
		resp.getWriter().write("Echo:"+ msg);
	}

	/*
	 * The servlet doesn't override the doPost(), doPut(), etc. methods
	 * in the parent class, so this servlet can't handle the corresponding
	 * HTTP methods. If you need to support POST requests, you would override
	 * doPost().
	 * 
	 */
	
}

package org.magnum.mobilecloud.servlet;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

/**

* An example of a very simple servlet that looks for a single request

* parameter and echos the parameter value back to the client using

* the "text/plain" content type.

* @author jules

public class EchoServlet extends HttpServlet // Servlets should inherit from HttpServlet

{

/**

* All HTTP GET requests that are routed to the servlet are handled by

* this method. All of the routing information about which requests

* should be sent to this servlet are handled in the web.xml file

* (see: src/main/webapp/WEB-INF/web.xml)

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse resp)

throws ServletException, IOException {

// Set the content type header that is going to be returned in the

// HTTP response so that the client will know how to display the

// result.

resp.setContentType("text/plain");

// Look inside of the HTTP request for either a query parameter or

// a url encoded form parameter in the body that is named "msg"

String msg = req.getParameter("msg");

// http://foo.bar?msg=asdf

// Echo a response back to the client with the msg that was sent

resp.getWriter().write("Echo:"+ msg);

}

* The servlet doesn't override the doPost(), doPut(), etc. methods

* in the parent class, so this servlet can't handle the corresponding

* HTTP methods. If you need to support POST requests, you would override

* doPost().

}

web.xml

<?xml version="1.0" encoding="ISO-8859-1" ?>

<!-- 
  The web.xml file provides basic information to the web container on 
  how to load your servlets into the container and which requests should
  be routed to each servlet.
 -->
<web-app xmlns="http://java.sun.com/xml/ns/j2ee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
    version="2.4">

    <display-name>Echo Application</display-name>
    <description>
        This is an application that will echo any message received via
        the msg parameter back to the client.
    </description>

    <!-- This set of directives tells the web application container about
         our servlet class so that it is loaded by the container -->
    <servlet>
        <servlet-name>EchoServlet</servlet-name>
        <servlet-class>org.magnum.mobilecloud.servlet.EchoServlet</servlet-class>
    </servlet>

    <!-- this set of directives tells the web application container which
         requests should be routed to our servlet. In this case, any request
         to the path '/echo' will be routed to the servlet. You can use wildcards
         for path matching. For example, '/echo/**' would match any sub path of
         '/echo/', such as '/echo/foo' and '/echo/bar' -->
    <servlet-mapping>
        <servlet-name>EchoServlet</servlet-name>
        <url-pattern>/echo</url-pattern>
        <!-- http://localhost:8080/echo -->
    </servlet-mapping>

</web-app>

<?xml version="1.0" encoding="ISO-8859-1" ?>

<!--

The web.xml file provides basic information to the web container on

how to load your servlets into the container and which requests should

be routed to each servlet.

-->

<web-app xmlns="http://java.sun.com/xml/ns/j2ee"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"

version="2.4">

<display-name>Echo Application</display-name>

This is an application that will echo any message received via

the msg parameter back to the client.

</description>

<!-- This set of directives tells the web application container about

our servlet class so that it is loaded by the container -->

<servlet-name>EchoServlet</servlet-name>

<servlet-class>org.magnum.mobilecloud.servlet.EchoServlet</servlet-class>

</servlet>

<!-- this set of directives tells the web application container which

requests should be routed to our servlet. In this case, any request

to the path '/echo' will be routed to the servlet. You can use wildcards

for path matching. For example, '/echo/**' would match any sub path of

'/echo/', such as '/echo/foo' and '/echo/bar' -->

<servlet-mapping>

<servlet-name>EchoServlet</servlet-name>

<url-pattern>/echo</url-pattern>

</servlet-mapping>

</web-app>