code: protected boolean isEncodeable(final String location) {
          //accessing protected methods using reflection:
          //return httpServletResponse.isEncodeable(location);
          boolean result=false;
          try{
              Method isEncodeable = HttpServletResponseImpl.class.getDeclaredMethod("isEncodeable", String.class);
              isEncodeable.setAccessible(true);
              result= (boolean) isEncodeable.invoke(httpServletResponse, location);
              isEncodeable.setAccessible(false);
          }catch(NoSuchMethodException | InvocationTargetException | IllegalAccessException e){
              UndertowServletLogger.ROOT_LOGGER.warn("Exception occured during invoking HttpServletResponseImpl.isEncodeable() method using reflection:",e);
              //FIXME: kakonyii: handle reflection errors or just omit them.
          }
          return result;
      }
docs: Return <code>true</code> if the specified URL should be encoded with
  a session identifier.  This will be true if all of the following
  conditions are met:
  <ul>
  <li>The request we are responding to asked for a valid session
  <li>The requested session ID was not received via a cookie
  <li>The specified URL points back to somewhere within the web
  application that is responding to this request
  </ul>
  
  @param location Absolute URL to be validated