Create a simple calculator application using servlet.

September 15, 2023

🧠 Simple Calculator Application Using Servlet | TYBScIT Sem 5 Practical

🎓 If you're learning Advanced Java or preparing for your TYBScIT Semester 5 practicals, this guide walks you through building a Servlet-based calculator application — step by step. The blog is based on a real-time screen recording demo and covers essential advanced programming in Java.

✅ What You Will Learn:

  • Create a Java Web Application in NetBeans
  • Use HTML forms to collect user input
  • Handle form data using a Java Servlet
  • Deploy on GlassFish Server
  • Output calculation results on a web browser

📽️ Step-by-Step Process (As Shown in the Video)

1️⃣ Create a Web Application Project

  • Open NetBeans IDE 8.2
  • Go to: File → New Project
  • Choose: Java Web → Web Application
  • Name the project (e.g., firstapp)
  • Select GlassFish Server and Java EE 7 Web

2️⃣ Design the Frontend (index.html)

Create the following form using HTML:

🌐 HTML 



<head><title>Calculator App</title></head><body>

        <form action="CalculatorServlet" ><br>

        Enter First Number <input type="text" name="txtN1"><br>

        Enter Second Number <input type="text" name="txtN2"><br>

        Select an Operation<br>

        <input type="radio" name="opr" value="+">ADDITION<br>

        <input type="radio" name="opr" value="-">SUBTRACTION<br>

        <input type="radio" name="opr" value="*">MULTIPLY<br>

        <input type="radio" name="opr" value="/">DIVIDE<br><br>

        <input type="reset">

        <input type="submit" value="Calculate"><br>

        </form></body></html>

🌐 JAVA 



package mypack;

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;

public class CalculatorServlet extends HttpServlet {

public void doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

response.setContentType("text/html;charset=UTF-8");

PrintWriter out = response.getWriter();

out.println("<html><head><title>Servlet CalculatorServlet</title></head><body>");

double n1 = Double.parseDouble(request.getParameter("txtN1"));

double n2 = Double.parseDouble(request.getParameter("txtN2"));

double result =0;

String opr=request.getParameter("opr");

if(opr.equals("+")) result=n1+n2; if(opr.equals("-")) result=n1-n2;

if(opr.equals("*")) result=n1*n2; if(opr.equals("/")) result=n1/n2;

out.println("<h1> Result = "+result); out.println("</body></html>");} }

🔍 Output Preview

4️⃣ Deploy and Run the Project

  • Right-click the project → Clean and Build
  • Then right-click → Run
  • Visit: http://localhost:8080/firstapp/index.html
  • Test inputs and operations in the browser

📘 Conclusion

This advanced java tutorial is perfect for TYBScIT Sem 5 students or anyone learning servlet-based Java applications. It teaches the fundamentals of advanced java concepts like servlets, form data handling, and server response logic.

If you're working on a final-year advanced java program, this is a great starting point.

Shah

Posted by Shah