public static boolean isJavaIdentifier(String s) {
        if(s.length()==0)   return false;
        if( reservedKeywords.contains(s) )  return false;

        if(!Character.isJavaIdentifierStart(s.charAt(0)))   return false;

        for (int i = 1; i < s.length(); i++)
            if (!Character.isJavaIdentifierPart(s.charAt(i)))
                return false;

        return true;
    }