JSON and Servlet example

In the previous section of JSON-Java example you have learned how to create a java class by using JSON classes. Now in this example we will tell you how to use JSON classes for creating Servlet.

In this example we have created an object of JSONArray and then we have added elements into this array by using the method add(). To have functionality of JSON in your application you must have JSON-lib and its supported jar files. These are: commons-lang.jar, commons-beanutils.jar, commons-collections.jar, commons-logging.jar, ezmorph.jar and json-lib-2.2.2-jdk15.jar.

Here is the example code of JSONServlet.java as follows:

JSONServlet.java


import java.io.*;

import javax.servlet.*;

import javax.servlet.http.*;

import net.sf.json.JSONArray;



public class JSONServlet extends  HttpServlet{

  public void doGet(HttpServletRequest request,

  HttpServletResponse response)

       throws ServletException,IOException{

 JSONArray arrayObj=new JSONArray();

 arrayObj.add("MCA");

 arrayObj.add("Amit Kumar");

 arrayObj.add("19-12-1986");

 arrayObj.add(24);

 arrayObj.add("Scored");

 arrayObj.add(new Double(66.67));

  PrintWriter out = response.getWriter();

  out.println(arrayObj);

  for(int i=0;i<arrayObj.size();i++){

  out.println(arrayObj.getString(i));

  }

  }

}

We have to do corresponding servlet mapping into web.xml as given below:


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



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

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

 xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 

 http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"

 version="2.5"> 

 <servlet>

  <servlet-name>JSONServlet</servlet-name>

  <servlet-class>JSONServlet</servlet-class>

  </servlet>

  <servlet-mapping>

  <servlet-name>JSONServlet</servlet-name>

  <url-pattern>/JSONServlet</url-pattern>

 </servlet-mapping>

</web-app>

To run this example follow this step by step procedure:

create a JSONServlet.java class
compile JSONServlet and place it into WEB-INF/classes directory
Download JSONLibraries and place it into Tomcat's lib directory
Start Tomcat Webserver and type
http://localhost:8080/JSON/JSONServlet into browser's address bar you will have following output on your browser.

Output:

Download JSON-Servlet Project code

JSON and Servlet example