Index.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>
CalculatorServlet.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
Index.html
<html>
<head>
<title>Login Form </title>
</head>
<form action="LoginServlet">
Enter User ID<input type="text" name="txtId"><br>
Enter Password<input type="password" name="txtPass"><br>
<input type="reset">
<input type="submit" value=" Click to Login ">
</form>
</html>
LoginServlet.java
package mypack;
import java.io.*;
import javax.servlet.ServletException;
import javax.servlet.http.*;
public class LoginServlet 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 LoginServlet</title></head>");
String uname = request.getParameter("txtId");
String upass = request.getParameter("txtPass");
if(uname.equals("admin") && upass.equals("12345")){
out.println("<body> bgcolor=blue >");
out.println("<h1> Welcome !!! "+uname+"</h1>");
}
else{
out.println("<body> bgcolor=red >");out.println("<h1> Login Fail !!! </h1>");
}
out.println("</body></html>");}}
Output
MySql queries
create database LoginDB;
use LoginDB;
create table user(username varchar(20) PRIMARY KEY, password varchar(20), email varchar(20),
country varchar(20));
insert into user values ('admin','admin','admin@gmail.com','India');
select * from user;
Index.html
<html><head><title>Registration Page</title></head><body>
<form action="RegisterServlet">
<H1>Welcome to Registration page</H1>
Enter User Name <input type="text" name="txtUid"><br>
Enter Password <input type="password" name="txtPass"><br>
Enter Email <input type="text" name="txtEmail"><br>
Enter Country <input type="text" name="txtCon"><br>
<input type="reset"> <input type="submit" value="REGISTER">
</form>
</body></html>
RegisterServlet.java
package mypack;
import java.io.*;
import java.sql.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class RegisterServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
String id = request.getParameter("txtUid");
String ps = request.getParameter("txtPass");
String em = request.getParameter("txtEmail");
String co = request.getParameter("txtCon");
try{
Class.forName("com.mysql.jdbc.Driver");
Connection con =DriverManager.getConnection("jdbc:mysql://localhost:3306/logindb");
PreparedStatement pst = con.prepareStatement("insert into user values(?,?,?,?)");
pst.setString(1,id);
pst.setString(2,ps);
pst.setString(3,em);
pst.setString(4,co);
int row = pst.executeUpdate();
out.println("<h1>"+row+ " Inserted Succesfullyyyyy");
}catch(Exception e){out.println(e);}
}
}
Output
Index.html
<html><head><title>Login Form</title></head>
<form action="LoginServlet" ><br>
Enter User ID <input type="text" name="txtId"><br>
Enter Password <input type="password" name="txtPass"><br>
<input type="reset">
<input type="submit" value=" Click to Login ">
</form></html>
LoginServlet.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;
import javax.servlet.RequestDispatcher;
public class LoginServlet 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("
out.println("
String uname = request.getParameter("txtId");
String upass = request.getParameter("txtPass");
if(uname.equals("admin") && upass.equals("servlet")){
RequestDispatcher rd = request.getRequestDispatcher("WelcomeServlet");
rd.forward(request, response);
}
else{
out.println("");
out.println("
Login Fail !!!
");RequestDispatcher rd = request.getRequestDispatcher("index.html");
rd.include(request, response);
}
out.println("");
out.println("");
}
}
WelcomeServlet.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;
import javax.servlet.RequestDispatcher;
public class LoginServlet 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("");
out.println("
String uname = request.getParameter("txtId");
String upass = request.getParameter("txtPass");
if(uname.equals("admin") && upass.equals("servlet")){
RequestDispatcher rd = request.getRequestDispatcher("WelcomeServlet");
rd.forward(request, response);
}
else{
out.println("");
out.println("
Login Fail !!!
");RequestDispatcher rd = request.getRequestDispatcher("index.html");
rd.include(request, response);
}
out.println("");
out.println("");
} }
Output
