how to redirect to a jsp page from a servlet

Question

well I have a jsp page with a login form, i'm using a servlet, if the username and password are correct the servlet redirects the user to another page else it redirects him to the login page again

when i log in with a correct username and password i'm redirected perfectly to reservation.jsp but when i put a wrong username or password in the form when i click on the submit button the page became blank

here is the servlet

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.*;

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

import com.mysql.jdbc.PreparedStatement;

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




public LogServlet() {
    super();

}



protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    response.setContentType("text/html");


    String name=request.getParameter("name");
    String password=request.getParameter("password");

    PreparedStatement ps = null;
    ResultSet rs = null;

    try {
        Class.forName("com.mysql.jdbc.Driver");
        Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/log",
                "root","");
        ps = (PreparedStatement) conn.prepareStatement("select nom_client,username,password from client where username = ? and password = ?");

        ps.setString(1, name);
        ps.setString(2, password);
        rs=ps.executeQuery();



    try {
        while(rs.next()){
        if(password.equals(rs.getString("password")) && name.equals(rs.getString("username"))){

        HttpSession session=request.getSession();
        session.setAttribute("name",name);
        PrintWriter out=response.getWriter();
        request.getRequestDispatcher("reservation.jsp").include(request, response);
        }
        else{
            response.sendRedirect("/login.jsp");

        }}
    } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();

    }
    System.out.close();


    }
    catch(Exception e){e.printStackTrace();}


}
}

Check this if this might be helpful to you http://stackoverflow.com/questions/18576159/automatically-redirect-from-one-jsp-page-to-another — Partha Bisoi, May 13 '15 at 10:23

score 2 · Answer 1 · answered May 13 '15 at 10:22

use request.getContextPath(), It will redirect you to login page.

response.sendRedirect(request.getContextPath()+"/login.jsp");

and if you are reaching to your login page in that case, pass request and response objects to your jsp page.

request.getRequestDispatcher(request.getContextPath()+"/login.jsp").forward(request,response);

Saif · Answer 2 · 2015-05-13T11:01:09.303

1

use this.

request.getRequestDispatcher("/login.jsp").forward(request,response);

As you have used

request.getRequestDispatcher("reservation.jsp").include(request, response);

to forward after successful login and as it is working, why not forwarding after failed also in this way .?

Which mean to use

request.getRequestDispatcher("/login.jsp").include(request, response);

edited May 13 '15 at 11:01

answered May 13 '15 at 10:22

Saif

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please be careful about the location of your login.jsp location. see if it is in the right location where in should be. – Saif May 13 '15 at 11:03
i have all the jsp files in the same location..i have tested your suggestion in another projet and it works perfectly, but not with that one – hichamx May 13 '15 at 11:17
try removing the slash `/` use `request.getRequestDispatcher("login.jsp").include(request, response); ` or `request.getRequestDispatcher("login.jsp").forward(request,response);` – Saif May 13 '15 at 11:25
the problem still persists – hichamx May 13 '15 at 11:51

score 1 · Answer 3 · answered May 13 '15 at 23:08

The problem could be here:

response.sendRedirect("/login.jsp");

This means that in the location header of the redirect response you will have:

http://localhost:8080/login.jsp

If you change it to:

response.sendRedirect("login.jsp");

than its relative to your webabb context path:

http://localhost:8080/app/login.jsp

Try with firebug or similar and trace down request/response you should find out quickly. And be sure jsp files are were expected in the hierarchy.

Hope this helps

score 0 · Answer 4 · edited May 13 '15 at 10:23

0

request.getRequestDispatcher("login.jsp").include(request, response);

Have u tried above code in else part ? I think it should work

edited May 13 '15 at 10:23

singhakash

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answered May 13 '15 at 10:22

Hiren patel

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score 0 · Answer 5 · answered May 13 '15 at 10:23

0

Problem is response.sendRedirect(...) does not prepend the context path where the resource (jsp) is bundled. Try using request.getRequestDispatcher(...) in both cases.

answered May 13 '15 at 10:23

Fran Montero

1,679
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which url are you redirected to? – Fran Montero May 13 '15 at 10:51
i'm not redirected at all in the browser a have the name of the servlet. but the page is blank – hichamx May 13 '15 at 11:00
What username and password aye you submitting? ¿Have you tried removing `while(rs.next()){` block? – Fran Montero May 13 '15 at 11:04
while(rs.next()){ i used it to compare the username and password with the data selected from the database – hichamx May 13 '15 at 11:19
when i remove it, even the fisrt redirect don't work – hichamx May 13 '15 at 14:45

score 0 · Answer 6 · answered May 06 '16 at 12:26

0

Rather than giving response.sendRedirect("\login.jsp"); use response.sendRedirect("/yourprojectname/"); and in welcome file in web.xml set login.jsp as welcome file.

answered May 06 '16 at 12:26

Saket Arora

1
4

score -1 · Answer 7 · edited May 06 '16 at 13:21

-1

Add this

response.sendRedirect("/yourprojectname/");

and set login.jsp as welcome file in web.xml

edited May 06 '16 at 13:21

Jean-Rémy Revy

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answered May 06 '16 at 12:29

Saket Arora

1
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response.sendRedirect("yourJsp Page"); – Saket Arora Oct 04 '16 at 07:28

score -1 · Answer 8 · edited May 13 '16 at 14:54

-1

The response from the database was empty, so I had to add that case to the class (via if/else condition).

edited May 13 '16 at 14:54

CubeJockey

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answered May 13 '16 at 13:17

hichamx

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In that case, just post an answer, if you think it will be helpful for others. – rghome May 13 '16 at 14:01

how to redirect to a jsp page from a servlet

8 Answers8