| trait BTree { | |
| fn size(&self) -> i32; | |
| fn sum(&self) -> i64; | |
| fn min(&self) -> i64; | |
| fn max(&self) -> i64; | |
| fn find(&self, value: i64) -> Option<i64>; | |
| } | |
| enum Node { | |
| Leaf { |
| // 絵の具を表すオブジェクト(副作用が伴う可変オブジェクト) | |
| public class Paint { | |
| private int volume; | |
| private PigmentColor pigmentColor; | |
| // getter, setter 省略 | |
| public Paint(PigmentColor pigmentColor, int volume) { | |
| this.volume = volume; | |
| this.pigmentColor = pigmentColor; | |
| } |
| case class Money(amount: BigDecimal, | |
| currency: Currency) { | |
| def plus(other: Money): Money = { | |
| require(currency == other.currency) | |
| new Money(amount = amount.add(other.amount), currency) | |
| } | |
| } |
| case class UserAcount(id: Long, name: String, groupId: Long) { | |
| // ... | |
| def groupName(groupRepository: GroupRepository): Task[GroupName] = groupRepository.resolveBy(groupId).map(_.name) | |
| } |
| package domain | |
| trait Money { | |
| def plus(other: Money): Money | |
| def minus(other: Money): Money | |
| // ... | |
| } |
トレイト: UserAccountRepository[M[_]] https://github.com/j5ik2o/scala-ddd-base/blob/master/example/src/main/scala/com/github/j5ik2o/dddbase/example/repository/UserAccountRepository.scala
実装: UserAccountRepositoryBySkinny https://github.com/j5ik2o/scala-ddd-base/blob/master/example/src/main/scala/com/github/j5ik2o/dddbase/example/repository/skinny/UserAccountRepositoryBySkinny.scala
があったとして、以下のようなDIをさせたいのですが、
| class ApiServer extends HttpApp { | |
| protected val design: Design = bind[Design] // ApiServerの外部で定義されているDesginを参照したい | |
| .bind[AtomicReference[ActorSystem]] | |
| .toInstance(systemReference) | |
| .bind[ActorSystem] | |
| .toInstanceProvider[AtomicReference[ActorSystem]](_.get) | |
| // snip | |
| package point | |
| import akka.actor.{Actor, ActorRef, ActorSystem, Props} | |
| import point.MainActor.Start | |
| import point.Point.{Distance, DistanceResult} | |
| import scala.concurrent.Await | |
| import scala.concurrent.duration._ | |
| object MainActor { |
| case class Room(id: Long, members: Seq[Member]) | |
| // このロジックはRoomが持つべき振る舞いだった場合（ドメインロジックがドメインオブジェクトの外側にある状態) | |
| room.copy(members = room.members :+ newMember) | |
| // ほんとは、こうしたらよいのでは | |
| case class Room(id: Long, members: Seq[Member]) { | |
| def addMember(value: Member): Room = | |
| copy(members = this.members :+ value) | |
| } | |
| room.addMember(newMember) |
| package app | |
| import cats.free._ | |
| import cats._ | |
| class DDD[ID, E] { | |
| def resolveBy(id: ID): Free[RepositoryDSL, Option[E]] = Free.liftF(ResolveBy(id)) | |
| def store(id: ID, entity: E): Free[RepositoryDSL, Unit] = Free.liftF(Store(id, entity)) |