request.sendRedirect is not working

Question

I'm trying to redirect from current page (index.jsp) after user logs in to another page. I get no error for this and can't really understand what the problem is. Here is my code of the servlet:

protected void doGet(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {
    response.getWriter().append("Served at: ").append(request.getContextPath());

    usernameInput = request.getParameter("username");
    passwordInput = request.getParameter("password");
    Connection conn = null;
    try {
        // Register JDBC driver
        Class.forName("com.mysql.jdbc.Driver");

        // Open a connection
        conn = DriverManager.getConnection(DB_URL, USER, PASS);

        // Execute SQL query
        String sql;
        sql = "SELECT * FROM `users` where Username=? and Password=?";
        PreparedStatement prepStmt = conn.prepareStatement(sql);
        prepStmt.setString(1, usernameInput);
        prepStmt.setString(2, passwordInput);
        ResultSet rs = prepStmt.executeQuery();

        if (rs.next()) {
            System.out.println("User login is valid in DB");
 //Here is where I try to log in. I tryed both the commented and uncommented way to log in but none seems to work.
            response.sendRedirect(request.getContextPath() + "resources/main.jsp");
            /*RequestDispatcher reqDisp = request.getRequestDispatcher("../WebContent/resources/main.jsp");
            reqDisp.forward(request, response);*/


        }
    } catch (Exception e) {
        System.out.println("validateLogon: Error while validating password: " + e.getMessage());
        try {
            throw e;
        } catch (Exception e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }
    } finally {
        try {
            conn.close();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

I can verify that it enters in the specific section of code since I see in the consele the message printed. If I could guess the problem, it may be I'm not giving the correct path for the main.jsp page. Here is how my project is structured.

Any ideas??Thanks!

Okay, so you know what redirect does? Open up the dev tools in your browser and see what URL the browser actually attempts to load in response to the redirect. http://stackoverflow.com/questions/20371220/what-is-the-difference-between-response-sendredirect-and-request-getrequestdis — Alan Hay, Aug 30 '16 at 17:38

score 1 · Answer 1 · answered Aug 30 '16 at 17:45

1

According to HttpServletRequest's API located here:

The path starts with a "/" character but does not end with a "/" character.

Therefore your line

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

May output some mashed-together string that isn't your intended path. Try debugging to the console the result of request.getContextPath() + "resources/main.jsp" and see if it is what you are trying to get to. You may need to change that line to:

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

Unrelated, but using doGet may not be the best idea here, since a GET request's parameters will be included in the URL - including your user's plain text password.

answered Aug 30 '16 at 17:45

Michael Guinn

117
1
8

What is the result ofSystem.out.println(request.getContextPath() + "resources/main.jsp"); – Michael Guinn Sep 01 '16 at 17:41
that's the result: /Sample_LogIn_Page/resources/main.jsp – Sep 04 '16 at 14:00
Are you able to navigate to that page directly? As in typing into the address bar "http:///Sample_LogIn_Page/resources/main.jsp Also how are you building your WAR? Is it named Sample_LogIn_Page.war and is the resources directory located in its root? – Michael Guinn Sep 05 '16 at 16:48
Yes I can access main.jsp normaly. – Sep 06 '16 at 20:14

request.sendRedirect is not working

1 Answers1