Question

Part I – Build a simple Servlet called MyServlet using NetBeans. Add this Servlet to you “ChattBank” Project. This MyServlet will display a message like “Go Braves” in a simple <h1> tag. Run this servlet from a Browser window by typing in the servlet name in the URL line.

(ie. http://localhost:8080/ChattBank/MyServlet). Make sure that your Server is up and running before you test this Servlet. The best way to do this is just Run your “ChattBank” Project once before you test the Servlet. Running the Project will start the Server.

Part II – Next, build a simple Servlet called LoginServlet in your “ChattBank” Project. Now make it so that when the Customer logs in, the LoginServlet will get called and will validate the user id and password.

1. At first, just make sure that the Servlet gets called correctly. So just print a simple message like “LoginServlet Running…”.
2. Remember, to call the LoginServlet, you will need to modify the FORM tag in the “Login.html” file:

<form action=”http://localhost:8080/ChattBank/LoginServlet”      method=”post”>

3. Test it out. When you click the Login Button on the LoginForm, you should see “LoginServlet Running….”

Part III – Now, modify the LoginServlet.

1. Make it so that when the Servlet gets called, it reads the id and password from the Login Form.

Use :    request.getParameter() to get these items. At first just read in these 2 strings and display them to the Server Log.

2.) If the id = “admin” and the Password = “123”, return an HTML page     that says “Valid Login”.

3.) If not return an HTML page that says “InValid Login”. Use out.println() to send these HTML messages.

     4.) Test out your WebApp.           

Part IV– Lastly, create a new LoginServletDB. This time we are going to go to the database to verify the user login. First look at the ChattBank database. There is a Customers table. In this table there is a UserID and a Passwd.

1. Write the database code, in your LoginServlet to let anyone of these customers login, using their own ids and passwords.(Hint: You will need to add all 6 database steps[Load Driver, get connection….] to your LoginServletDB. Then get the password from the database abd compare it to the one you read from the HTML file.
2. Remember, to call the LoginServletDB, you will need to modify the FORM tag in the “Login.html” file:

<form action=”http://localhost:8080/ChattBank/LoginServletDB"

ALSO NEED HELP CONNECTING DATABASE AND HOW TO ADD THE ACCCESS FILES TO NETBEANS

Answer 1

Answers:

I have used Mysql database. so use suitable jdbc driver to run this code. Drivers are mentioned in lib folder. Please find screenshot of project structure for the same .

Part I :

package com.test;

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

/**
* Servlet implementation class MyServlet
*/
@WebServlet("/MyServlet")
public class MyServlet extends HttpServlet {
   private static final long serialVersionUID = 1L;

/**
* Default constructor.
*/
public MyServlet() {
  
}

   /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
   protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
       // TODO Auto-generated method stub
       response.getWriter().append("<h1>Go Braves</h1>");
   }

}

===============================================================================================

Part II & III

LoginServlet.java

package com.test;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
* Servlet implementation class LoginServlet
*/
@WebServlet("/LoginServlet")
public class LoginServlet extends HttpServlet {
   private static final long serialVersionUID = 1L;

/**
* @see HttpServlet#HttpServlet()
*/
public LoginServlet() {
super();
// TODO Auto-generated constructor stub
}

   /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
   protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
      
       PrintWriter out = response.getWriter();
       String id = request.getParameter("id");
       String password = request.getParameter("password");
      
       if(null != id && null != password && id.equals("admin") && password.equals("123")) {
           response.sendRedirect("http://localhost:8080/ChattBank/ValidLogin.html");
       }else {
           out.println("InValid Login");
       }
   }

}
---------------------------------------------------------------------------------------------------------------------------------------------------------------------

Login.html

<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Login</title>
</head>
<body>

<!-- for Part II & III -->
<form action="http://localhost:8080/ChattBank/LoginServlet" method="post">
ID:<input type="text" name="id"/><br/><br/>
Password:<input type="password" name="password"/><br/><br/>
<input type="submit" value="login"/>
</form>

</body>
</html>

---------------------------------------------------------------------------------------------------------------------------------------------------------------------

ValidLogin.html

<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
   <h1>Valid Login</h1>
</body>
</html>

---------------------------------------------------------------------------------------------------------------------------------------------------------------------

Part IV

Creation of database

create table Customers (
UserID char(20),
Passwd char(20)
);

insert into Customers values ("admin", "123");

---------------------------------------------------------------------------------------------------------------------------------------------------------------------

LoginServletDB.java

package com.test;

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
* Servlet implementation class LoginServletDB
*/
@WebServlet("/LoginServletDB")
public class LoginServletDB extends HttpServlet {
   private static final long serialVersionUID = 1L;

/**
* @see HttpServlet#HttpServlet()
*/
public LoginServletDB() {
super();
}

   /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
   protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
      
       PrintWriter out = response.getWriter();
       String id = request.getParameter("id");
       String password = request.getParameter("password");
      
       try {
           Class.forName("com.mysql.jdbc.Driver");
           Connection con=DriverManager.getConnection(
           "jdbc:mysql://localhost:3306/test","root","root123");
          
           PreparedStatement ps=con.prepareStatement(
           "select * from Customers where UserID=? and Passwd=?");
           ps.setString(1,id);
           ps.setString(2,password);
          
           ResultSet rs=ps.executeQuery();
           boolean status = rs.next();
          
           if(status) {
               response.sendRedirect("http://localhost:8080/ChattBank/ValidLogin.html");
           }else {
               out.println("InValid Login");
           }
          
       } catch (ClassNotFoundException e) {
           e.printStackTrace();
       } catch (SQLException e) {
           e.printStackTrace();
       }
      
   }

}

--------------------------------------------------------------------------------------------------------------------------------------------------------------------

Login.html

<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Login</title>
</head>
<body>

<!-- for Part IV -->
<form action="http://localhost:8080/ChattBank/LoginServletDB" method="post">
ID:<input type="text" name="id"/><br/><br/>
Password:<input type="password" name="password"/><br/><br/>
<input type="submit" value="login"/>
</form>

</body>
</html>

----------------------------------------------------------------------------------------------------------------------------------------------------------

ValidLogin.html

<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
   <h1>Valid Login</h1>
</body>
</html>

==============================================================================================

Screenshots: