generate an uuid string concode_field_sep PlaceHolder placeHolder concode_field_sep String hexSHA1 concode_elem_sep String encodeBASE64 concode_elem_sep String encodeBASE64 concode_elem_sep byte[] decodeBASE64 concode_elem_sep byte[] hexStringToByte concode_elem_sep String hexMD5 concode_elem_sep String byteToHexString
String function ( ) { return UUID . randomUUID ( ) . toString ( ) ; }