This is the standard approach of Java web application that we should always create a design layer under JSP and code layer under servlet.
It is also called the 2-tier architecture of java means we work on two different layers then it will be 2-tier.
Step by Step Implementation of Java Web Development:-
Step1st:- Create a JSP web page and design form using HTML Form Content.
<form action="ServletName" method="post">
</form>
Step2nd:- Create Servlet and Write Code under doPost() in eclipse otherwise in Netbeans processRequest() which is used define method which will be called under doGet() and doPost()
int a = Integer.parseInt(request.getParameter("textfiledname"));
request is the Object of HttpRequest class and getParameter() is used to get the data of HTML component(textfield,radio,checkbox,etc)
Complete Code explanation:
</form>
Step2nd:- Create Servlet and Write Code under doPost() in eclipse otherwise in Netbeans processRequest() which is used define method which will be called under doGet() and doPost()
int a = Integer.parseInt(request.getParameter("textfiledname"));
request is the Object of HttpRequest class and getParameter() is used to get the data of HTML component(textfield,radio,checkbox,etc)
Complete Code explanation:
Code of JSP:-
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>JSP Page</title>
</head>
<body>
<form method="post" action="AdditionSer">
<input type="text" name="txtnum1" placeholder="Enter First Number" />
<br>
<br>
<input type="text" name="txtnum2" placeholder="Enter Second Number" />
<br>
<br>
<input type="submit" name="btnsubmit" value="Submit" />
</form>
</body>
</html>
Code of Servlet for Netbeans:-
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 AdditionSer extends HttpServlet {
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
try (PrintWriter out = response.getWriter()) {
/* TODO output your page here. You may use following sample code. */
int a = Integer.parseInt(request.getParameter("txtnum1"));
int b = Integer.parseInt(request.getParameter("txtnum2"));
int c = a+b;
out.print("result is "+c);
}
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>JSP Page</title>
</head>
<body>
<form method="post" action="AdditionSer">
<input type="text" name="txtnum1" placeholder="Enter First Number" />
<br>
<br>
<input type="text" name="txtnum2" placeholder="Enter Second Number" />
<br>
<br>
<input type="submit" name="btnsubmit" value="Submit" />
</form>
</body>
</html>
Code of Servlet for Netbeans:-
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 AdditionSer extends HttpServlet {
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
try (PrintWriter out = response.getWriter()) {
/* TODO output your page here. You may use following sample code. */
int a = Integer.parseInt(request.getParameter("txtnum1"));
int b = Integer.parseInt(request.getParameter("txtnum2"));
int c = a+b;
out.print("result is "+c);
}
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
Code for Servlet in eclipse
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
PrintWriter out = response.getWriter();
int a = Integer.parseInt(request.getParameter("txtnum1"));
int b = Integer.parseInt(request.getParameter("txtnum2"));
int c = a+b;
out.print(c);
}
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