public String toUuidString(){
  String result=String.join("-",contentAsHex(0,4),contentAsHex(4,6),contentAsHex(6,8),contentAsHex(8,10),contentAsHex(10,16));
  return result.toLowerCase();
}

public String toUuidString ( ) { String result = String . join ( "-" , contentAsHex ( 0 , 4 ) , contentAsHex ( 4 , 6 ) , contentAsHex ( 6 , 8 ) , contentAsHex ( 8 , 10 ) , contentAsHex ( 10 , 16 ) ) ; return result . toLowerCase ( ) ; }
uuid created from the first 128 bits of sha256
