Go Blog: Membuat Kalkulator Sederhana Dengan Servlet

Sekarang kita bahas Materi baru yaitu Sevlet. dari pada panjang leba ngocehnya mending kita langsung ke prakteknya aja ya.. oo iy sebelumnya kalian harus instal netbeans dulu dan pastikan tomcatnya juga ke instal

nah langsung aja deh ikutin langkah - langkahnya dengan melihat gambar di bawah ini :
pertama buat project baru...

lalu klik next.. selanjutnya samakan Context Path nya dengan gambar berikut :

lalu kita akan membuat sebuah kelas sevlet.. ikuti langkah" di bawah ini..

Nah Sekarang kita sudah buat kelas dengan nama kalkulator.. Sekarang anda coba copy paste source code berikut di klas kalkulator tadi :
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/

package kalkulator;

import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
*
* @author Lukmanul Hakim
*/
public class kalkulator extends HttpServlet {

    /**
     * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        try {
            out.println("<html>");
            out.println("<head>");
            out.println("<title>Kalkulato Servlet</title>");

            out.println("</head>");
            out.println("<body><center>");
            out.println("<h1 >Kalkulator</h1>");
            //Please Enter two values
            out.println("<form method='post' action='kalkulator'>");
            out.print("<p>angka 1: <input type='text' name ='angka1' ></p>");
            out.println("<p><select name='operator'>"+
                       "<option value = '+'>+</option>" +
                       "<option value = '-'>-<" + "/option>" +
                       "<option value = '*'>*</option>" +
                       "<option value = '/'>/</option>" +
                       "</select></p>" );
            out.print("<p>angka 2: <input type='text' name ='angka2' ></p>");
            out.print("<p><input type='submit' name ='submit' value ='='><p>");
            out.println("</form>");

            int v1 = Integer.parseInt (request.getParameter("angka1"));
            int v2 = Integer.parseInt(request.getParameter("angka2"));
            String operator = request.getParameter("operator");

            int hasil;
            if ("+".equals(operator))
                hasil = v1+v2;
            else if ("-".equals(operator))
                hasil = v1-v2;
            else if ("*".equals(operator))
                hasil = v1*v2;
            else
                hasil = v1/v2;
            out.print("<p> hasil: <input type='text' name ='value1' value ='"+hasil+"'></p>");
            out.println("</center></body>");
            out.println("</html>");

        } finally {
            out.close();
        }
    }

    // <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
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    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
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    }

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

}

Jika sudah anda harus mengedit file xmlnya dulu agar bisa di running. Ikuti langkah berikut ini :
buka file web.xml