Redirect to another action in Interceptor

[Krishna Nagadev]

Actions are wrapped with interceptors and these configuration we kept it in struts.xml

Instead of controlling it at configuration level, I want to bypass the execution of Action/next interceptors in the stack from interceptor itself.. dynamically .. is it really possible ?
Let me explain my problem in detail here..

I need to check a cookie at interceptor and need to execute different actions based on cookie value.. I tried in below way, I am able to redirect the response to desired action and page but with exceptions. Here is the code ..

   if(cookieExists==false){                  
    
      response.sendRedirect(differntUrl);  
      return null;   
   }  
   return invocation.invoke(); 

Error Message
java.lang.IllegalStateException: Cannot create a session after the response has been committed
org.apache.catalina.connector.Request.doGetSession(Request.java:2301)

[David Newton]

http://struts.apache.org/2.x/docs/writing-interceptors.html

You probably need a PreResultListener.

[Krishna Nagadev]

Thanks David,

But I dont want to execute the Action, instead I want to redirect/forward to some other action from interceptor. if I choose PreResultListener then it will be called before the result is being executed. ie after execution of your Action. I dont want to happen in my case. Please let me know if any thoughts

[David Newton]

Oh; include the full source of your interceptor then. Or just look at the source for something like the workflow interceptor and see what you're doing wrong.

[Krishna Nagadev]

Here is the intercept method of my interceptor.

public String intercept(ActionInvocation invocation) throws Exception {
		
		HttpServletRequest request = (HttpServletRequest)invocation.getInvocationContext().get(StrutsStatics.HTTP_REQUEST);
		HttpServletResponse response = (HttpServletResponse)invocation.getInvocationContext().get(StrutsStatics.HTTP_RESPONSE);
		
		String requestedUrl = request.getRequestURI();
		String anotherActionUrl ="/check/anotherAction.go";
		boolean cookieExists = false;
		
		
		if(request!=null && request.getCookies()!=null){
			
			Cookie[] cookies  = request.getCookies();
			for(Cookie cookie:  cookies){
				logger.info(cookie.getName());
				if(cookie.getName().equalsIgnoreCase("myCookie")){
					cookieExists = true;
					break;
				}
			}
		}
			if(cookieExists==false){
				ServletContext sc = (ServletContext)ServletActionContext.getServletContext();
				sc.getRequestDispatcher(anotherActionUrl).forward(request, response);
                                //response.sendRedirect(request.getContextPath()+anotherActionUrl);
				//return null;
			}
		
		return invocation.invoke();
		
	}

[David Newton]

Did you try it by using a normal S2 result rather than doing a sendRedirect? That's a better solution anyway.

I'm pretty sure you don't want a forward anyway, since that'd show the original URL in the browser bar.

[Krishna Nagadev]

I may require to forward the request because I need to resend the same parameters that I received as part of request. That is a different problem again ;)
Can you suggest me how to redirect to S2 Action instead of response.sendRedirect() from Interceptor ?

Thanks for your help again

[David Newton]

Return the name of a global result.

[Krishna Nagadev]

OK thanks. I will try that

[Sandeep Murthy]

You should stop getting the "Result already committed" error message if you remove the "return null" statement after the redirect.

Explanation:

When you return null, the default result gets executed.
Since you have already done a response.sendRedirect(), you will get the error message when you try to forward again as per the default result.