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Servlet controller and RequestDispatcher

Hi Experts,

I am trying to control all users' requests by one servlet and then it passes it to the next servlet based on the request. However, I only get blank page instead of welcome page if I request from  login page.

This is what I did.
+++++++++++++++++++++

login.html

...
<FORM ACTION="RegistrationController" METHOD="POST">
...
...
++++++++++++++++

public class RegistrationController extends HttpServlet {
   
    protected void doGet(HttpServletRequest request,
            HttpServletResponse response)
            throws ServletException, java.io.IOException {
               
                RequestDispatcher rd = request.getRequestDispatcher("/LoginServlet");
                rd.include( request, response ) ;  
...
...
++++++++++++
public class LoginServlet extends HttpServlet {
   
   
     protected void doGet(HttpServletRequest request,
             HttpServletResponse response)
             throws ServletException, java.io.IOException {
         response.sendRedirect("/AS4/welcome.html");
....
...
++++++++++++
      <servlet>
            <servlet-name>RegistrationController</servlet-name>
            <servlet-class>RegistrationController</servlet-class>
      </servlet>
      <servlet>
            <servlet-name>LoginServlet</servlet-name>
            <servlet-class>LoginServlet</servlet-class>
      </servlet>
      
      <servlet-mapping>
           <servlet-name>RegistrationController</servlet-name>
           <url-pattern>/RegistrationController</url-pattern>
        </servlet-mapping>

        <servlet-mapping>
           <servlet-name>LoginServlet</servlet-name>
           <url-pattern>/*</url-pattern>
        </servlet-mapping>
+++++++++++

thanks in advance
0
dkim18
Asked:
dkim18
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1 Solution
 
mukundha_expertCommented:
if you are getting the correct URL on the browser then try including or forwarding to the welcome.html  instead of redirecting it in LoginServlet

0
 
dkim18Author Commented:
I don't think I am getting correct url. This is url that I got:

http://localhost:8080/AS4/RegistrationController

and acutally, there is error message on the screen that says:

The requested resource (/AS4/LoginServlet) is not available

0
 
mukundha_expertCommented:
try,

public class RegistrationController extends HttpServlet {
   
    protected void doGet(HttpServletRequest request,
            HttpServletResponse response)
            throws ServletException, java.io.IOException {
               
                RequestDispatcher rd = request.getRequestDispatcher("/LoginServlet");
               ////////************ rd.include( request, response ) ;  

              rd.forward(request,response) ;

...
...



>>>>>>>>>>>> use system.out.println() in both the servlets, you can easily find where it is going wrong. rd.include() did not work. coz include includes the output of the other servlet into this. forward() gives the control to the new servlet.

check,

http://www.brics.dk/~amoeller/WWW/servlets/dispatch.html


0
 
mukundha_expertCommented:
also try changing this,

<servlet-mapping>
           <servlet-name>LoginServlet</servlet-name>
           <url-pattern>/LoginServlet</url-pattern>
        </servlet-mapping>
0
 
dkim18Author Commented:
Yes, it worked. I didn't even have to change servlet mapping. Thanks!
0
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