public static String toStringWordCharsOnly(String s){
    return (s == null) ? "null" : s.replaceAll("[\\W]", "").toLowerCase();
  }
Return alphanumeric(and '_') chars only of a string, lowercased
hcatalog/webhcat/java-client/src/main/java/org/apache/hive/hcatalog/api/repl/ReplicationUtils.java