Sorting

Ids are roughly sortable. Like Twitter Snowflake they are k-sorted. The default Ordering, which is defined implicitly, sorts ids first by the timestamp, then by the node and then by the sequence. Sorting ids as Strings or Longs will produce the same result.

import gr.jkl.uid.Id

val ids = List.fill(1000)(Id(util.Random.nextLong))

val sortedIds = ids.sorted

val longIds = ids.map(_.underlying)

val sortedLongIds = longIds.sorted

val stringIds = ids.map(_.toString)

val sortedStringIds = stringIds.sorted

sortedLongIds == sortedIds.map(_.underlying)
// res0: Boolean = true

sortedStringIds == sortedIds.map(_.toString)
// res1: Boolean = true

It’s easy to implement an ordering for a class which contains an id.

import gr.jkl.uid.Id
import scala.math.Ordering

case class Comment(id: Id, commenter: String, body: String)

object Comment {
  implicit val IdOrdering: Ordering[Comment] = Ordering by (_.id)  
}

Alternatively, you can sort ids first by the timestamp, then by the sequence and then by the node. This ordering requires a scheme.

import gr.jkl.uid.{ Id, Scheme }

val ids = List.fill(1000)(Id(util.Random.nextLong))

implicit val scheme = Scheme(44, 12, 8, 1351728000000L)

val sortedIds = ids.sorted(Id.TimeSequenceNodeOrdering)