Overcome duplicate form submission in Struts

There are three parts of any struts code which we use for validation of user fields:

1) Form Bean

2) Form Action

3) Submit Action

With appropriate use of tokens in these classes we can avoid duplicate form submission, a vector for Cross Site Request Forgery (CSRF of XSRF).

Where to use:
1) Inside Form Bean:
   Right after instantiating Action Error inside Validate() method write below lines:

   String token =request.getParameter("org.apache.struts.taglib.html.TOKEN");
    if(isToken!==null)
        {
              //write your validation code here
         }
2) Inside Form Action:
    Right after instantiating FormBean, put below line:
         saveToken(request);

3) Now, the turn of Submit Action:
     isTokenValid(request)
        {
           //Write all your valitaion code here
        }
    Close the loop and put a suitable redirect in case validation fails.

4) The knotty stuffs needed now
 > Make entry for redirection in struts.config file in case the validation fails.
 > Create a jsp with error message and make entry of this jsp in tiles.xml.
    One simple example of error.jsp:
    Unable to access the page you are looking.