import java.io.*; import java.util.*; import javax.servlet.*; import javax.servlet.http.*; public class LoginHandler extends HttpServlet { public void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException { res.setContentType("text/html"); PrintWriter out = res.getWriter(); // Get the user's account number, password, and pin String account = req.getParameter("account"); String password = req.getParameter("password"); String pin = req.getParameter("pin"); // Check the name and password for validity if (!allowUser(account, password, pin)) { out.println("Access Denied"); out.println("Your login and password are invalid.
"); out.println("You may want to try again"); out.println(""); } else { // Valid login. Make a note in the session object. HttpSession session = req.getSession(); session.setAttribute("logon.isDone", account); // just a marker object // Try redirecting the client to the page he first tried to access try { String target = (String) session.getAttribute("login.target"); if (target != null) { res.sendRedirect(target); return; } } catch (Exception ignored) { } // Couldn't redirect to the target. Redirect to the site's home page. res.sendRedirect("/"); } } protected boolean allowUser(String account, String password, String pin) { return true; // trust everyone } }