code: public boolean isWrapperFor(ServletRequest wrapped) {
          if (request == wrapped) {
              return true;
          } else if (request instanceof ServletRequestWrapper) {
              return ((ServletRequestWrapper) request).isWrapperFor(wrapped);
          } else {
              return false;
          }
      }
docs: Checks (recursively) if this ServletRequestWrapper wraps the given
  {@link ServletRequest} instance.
  
  @param wrapped the ServletRequest instance to search for
  
  @return true if this ServletRequestWrapper wraps the
  given ServletRequest instance, false otherwise
  
  @since Servlet 3.0