Question

Well OK, I got confused. I believe it returns the pointer to the original map?

    private HttpServletRequest originalRequest;
    Map params = originalRequest.getParameterMap();
      params.remove("parameter-to-remove");
      params.put("parameter-to-add", "<a value>");

Now are the parameters in the originalRequest going to change after these actions? Or does it just copy the values to params and it doesn’t matter what I do with them and nothings going to be changed in originalRequest?

Answer 1

No, you are not allowed to remove or add any request parameter(s) to the request object. They must remain (as they arrived to the server) until the request object goes out of scope (after the end of the request processing cycle).

Logically, if you were allowed to do something like that, then the request object would not represent the original request any more. During the whole request processing cycle, we want to process the request sent by the client, not the one that has been tampered.

The method you should use instead is void setAttribute(java.lang.String name, java.lang.Object o).