typeclasses-example

Typeclasses.scala

package com.hiya.h4b.cpas.service

import java.time.Instant
import java.time.Instant.now

import akka.http.scaladsl.model.StatusCode
import akka.http.scaladsl.model.StatusCodes.{Created, NotFound, OK}

object Typeclasses extends App {

  trait Statusable[T] {
    def isSuccess(t: T): Boolean
  }

  object Statusable {
    def apply[T](implicit instance: Statusable[T]): Statusable[T] = instance
  }

  implicit def statusableInstant: Statusable[Instant] = new Statusable[Instant] {
    override def isSuccess(i: Instant): Boolean = i.isAfter(now())
  }

  implicit def statusableStatusCode: Statusable[StatusCode] = new Statusable[StatusCode] {
    override def isSuccess(s: StatusCode): Boolean = s.isSuccess()
  }

  def getCommonStatus[T: Statusable](statusebles: Set[T]): Boolean =
    statusebles.forall(Statusable[T].isSuccess(_))

  println(getCommonStatus(Set[StatusCode](OK, Created)))
  println(getCommonStatus(Set[StatusCode](NotFound)))
  println(getCommonStatus(Set(now().plusSeconds(2), now().plusSeconds(5))))
  println(getCommonStatus(Set(now().plusSeconds(2), now().minusSeconds(60))))
}