Convert Key Example with JSON

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package edu.sc.cse;

import java.io.*;
import java.net.*;

import javax.servlet.*;
import javax.servlet.http.*;

import org.json.simple.JSONObject;

/**
 *
 * @author jmvidal
 */
public class AjaxResponseServlet extends HttpServlet {
   
    /** 
    * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
    * @param request servlet request
    * @param response servlet response
    */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        // key is the parameter passed in from the javascript
        // variable named url (see index.html)
        String key = request.getParameter("key");

        if (key != null) {

            // extract the first character from key
            // as an int, then convert that int to a String
            int keyInt = key.charAt(0);
            // setup the response
            response.setContentType("text/xml");
            response.setHeader("Cache-Control", "no-cache");
            // write out the xml string
            String outString = createJSONwithJSONsimple(keyInt);
            response.getWriter().write(outString);
        } else {
            // If key comes back as a null, return a question mark.
            response.setContentType("text/xml");
            response.setHeader("Cache-Control", "no-cache");
            response.getWriter().write("?");
        }
    }

    public String createJSONwithJSONsimple(int keyInt) {
        JSONObject obj = new JSONObject();
        JSONObject obj2 = new JSONObject();

        obj2.put("decimal", Integer.toString(keyInt));
        obj2.put("hexadecimal", Integer.toString(keyInt, 16));
        obj2.put("octal", Integer.toString(keyInt, 8));
        obj2.put("hyper", "&0x" + Integer.toString(keyInt, 16));
        obj2.put("binary", Integer.toString(keyInt, 2) + "B");

        obj.put("conversion", obj2);
        return (obj.toString());
    }

    public String createStringBufferJSON(int keyInt) {

        StringBuffer returnJSON = new StringBuffer("\r\n{\"conversion\":{");
        returnJSON.append("\r\n\"decimal\": \"" +
                Integer.toString(keyInt) + "\",");
        returnJSON.append("\r\n\"hexadecimal\": \"" +
                Integer.toString(keyInt, 16) + "\",");
        returnJSON.append("\r\n\"octal\": \"" +
                Integer.toString(keyInt, 8) + "\",");
        returnJSON.append("\r\n\"hyper\": \"&0x" +
                Integer.toString(keyInt, 16) + "\",");
        returnJSON.append("\r\n\"binary\": \"" +
                Integer.toString(keyInt, 2) + "B\"");
        returnJSON.append("\r\n}}");
        return returnJSON.toString();
    }

    // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
    /** 
     * Handles the HTTP <code>GET</code> method.
     * @param request servlet request
     * @param response servlet response
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /** 
     * Handles the HTTP <code>POST</code> method.
     * @param request servlet request
     * @param response servlet response
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        processRequest(request, response);
    }

    /** 
     * Returns a short description of the servlet.
     */
    public String getServletInfo() {
        return "Short description";
    }
    // </editor-fold>
}