is there any way to add new http prams

[Meir Yan]

Hello all
I wander if can shove another http param even if I didn�t send it throw submit
before the the request.getParameterMap(); capture it ?

The reason is :
there is already working system that handling the request paramets I like it to handle another paramer on the way before it retched to the request.getParameterMap();
[ August 31, 2006: Message edited by: Bear Bibeault ]

[Ben Souther]

You could wrap the request object from a filter and override the getParameterMap method.

[Meir Yan]

can you show me example please ?

[Ben Souther]

The closest example I have is one that wraps the response object and writes the servlet's output to stdout before sending to the browser.

See http://simple.souther.us/capture.war.
[ August 31, 2006: Message edited by: Ben Souther ]

[Meir Yan]

thanks for the example i just miss informetion how to use it with jsp

[Ben Souther]

You won't be able to do this from a JSP page.
It will involve some java coding

[Meir Yan]

no problem about java coding but how i implement it with jsp ?

[Bear Bibeault]

You won't be able to do this from a JSP page.

[Stefan Evans]

If you want to add a parameter to the request before it gets to this JSP, your best bet is probably to use a ServletFilter.

It can intercept all incoming requests to specified resources, and gives you the chance to run java code before/after invoking the requested resource.
You would need something like this in web.xml. This example shows the filter applying to one JSP only. By setting the url-pattern you can have it affect any resource you like.

<filter>
    <filter-name>MyFilter</filter-name>
    <filter-class>com.mypackage.MyFilter</filter-class>
  </filter>
  <filter-mapping>
    <filter-name>MyFilter</filter-name>
    <url-pattern>theJspIWantToAffect.jsp</url-pattern>
  </filter-mapping>

And then in the MyFilter class something like this:

 public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain) throws IOException, ServletException{
 
    // write a class which allows editing of parameters
    HttpRequestWithModifiableParameters wrappedRequest = new HttpRequestWithModifiableParameters (request);
    // set the new parameter
    wrappedRequest.setParameter("newParam", "newParamValue");
    // pass the wrapped request (with the new parameter) on down the chain.
    chain.doFilter(wrappedRequest, response);
  }

You can find a related post in another forum

[Manzar Zaidi]

I could add additional parameters to a request forwarding it through a jsp and using jsp:forward actions which let you embed jsp:param inside them, thus adding more actual request parameters to the request.