docs: synchronized public boolean load(URL groupedSetUrl) {
  		if (groupedSetUrl == null) {
  			throw new RuntimeException("Null GroupSet url define!");
  		}
  		// log.debug("Load GroupSet file [{}]", groupedSetUrl.getPath());
  		InputStream settingStream = null;
  		try {
  			settingStream = groupedSetUrl.openStream();
  			load(settingStream);
  		} catch (IOException e) {
  			// log.error(e, "Load GroupSet error!");
  			return false;
  		} finally {
  			IoUtil.close(settingStream);
  		}
  		return true;
  	}