code: public ResponseCtx makeResponseCtx(String response)
              throws MelcoeXacmlException {
          ResponseCtx resCtx = null;
          try {
              ByteArrayInputStream is =
                      new ByteArrayInputStream(response.getBytes());
              resCtx = ResponseCtx.getInstance(is);
          } catch (ParsingException pe) {
              throw new MelcoeXacmlException("Error parsing response.", pe);
          }
          return resCtx;
      }
docs: Converts a string based response to a ResponseCtx obejct.
  
  @param response
  the string response
  @return the ResponseCtx object
  @throws MelcoeXacmlException