code: public static void unregisterURLRewriter( ServletRequest request, URLRewriter rewriter )
      {
          if ( rewriter == null ) { return; }
  
          ArrayList/*< URLRewriter >*/ rewriters = getRewriters( request );
  
          if ( rewriters == null )
          {
              return;
          }
          else
          {
              rewriters.remove( rewriter );
  
              if ( rewriters.size() == 0 )
              {
                  request.removeAttribute( URL_REWRITERS_KEY );
              }
          }
      }
docs: Unregister the URLRewriter (remove from the list) from the request.
  
  @param request the current ServletRequest.
  @param rewriter the URLRewriter to unregister
  @see #registerURLRewriter