protected String cleanAppId(String appId) {
    return (appId != null) ? StringUtil.cleanseToken(appId) : Constants.UNKNOWN;
  }
protected String cleanAppId ( String appId ) { return ( appId != null ) ? StringUtil . cleanseToken ( appId ) : Constants . UNKNOWN ; }
Given a potential value for appId, return a string that is safe to use in
the jobKey

@param appId
possibly null value.
@return non-null value stripped of separators that are used in the jobKey.