code: public String processOutbound(final HttpServletRequest request, final HttpServletResponse response,
              final RewriteRule rule, final String url)
     {
        String result = url;
        if ((rule != null) && rule.isOutbound() && rule.matches(url))
        {
           for (Processor p : processors)
           {
              result = p.processOutbound(request, response, rule, result);
           }
        }
        return result;
     }
docs: Rewrite the given URL using the provided {@link RewriteRule} object. Process the URL only if the rule is set to
  outbound="true"
  
  @return The rewritten URL, or the unchanged URL if no action was taken.