abstract-entity-base-and-uuid.ts

abstract class Entity<T> {
  public readonly id: T
  protected abstract nextID(): T
  constructor(id?: T) {
    this.id = id || this.nextID()
  }
}

class EntityWithUUID extends Entity<UUID> {
  protected nextID(): UUID {
    return new UUID()
  }
}

class EntityWithObjectID extends Entity<ObjectID> {
  protected nextID(): ObjectID {
    return new ObjectID()
  }
}

class UUID {
  public readonly value: string = 'Mock UUID'
}

class ObjectID {
  public readonly value: string = 'Mock ObjectID'
}

class Author extends EntityWithUUID {}

class Book extends EntityWithObjectID {}

const a = new Author()
const b = new Book()

console.log(a.id.value)
console.log(b.id.value)