Subscription Rate-Plan Domain Model (PlantUML)

@startuml
title Subscription rate-plan domain model
class Product {
  +code : String
  +name : String
  +family : String
}
class RatePlan {
  +code : String
  +currency : String
  +billingPeriod : Period
  +effectiveFrom : Date
  +effectiveTo : Date
}
class Charge {
  +name : String
  +type : ChargeType
  +model : PricingModel
}
class PriceTier {
  +fromQuantity : int
  +toQuantity : int
  +unitPrice : Decimal
}
class Subscription {
  +number : String
  +startDate : Date
  +termMonths : int
  +autoRenew : boolean
}
class SubscriptionItem {
  +quantity : int
  +discountPercent : Decimal
}
class Amendment {
  +type : AmendmentType
  +effectiveDate : Date
  +prorate : boolean
}
enum ChargeType {
  RECURRING
  USAGE
  ONE_OFF
}
enum PricingModel {
  FLAT
  PER_UNIT
  TIERED
  VOLUME
}
enum AmendmentType {
  UPGRADE
  DOWNGRADE
  RENEWAL
  CANCELLATION
}
Product "1" o-- "*" RatePlan
RatePlan "1" *-- "*" Charge
Charge "1" *-- "*" PriceTier
Subscription "1" *-- "*" SubscriptionItem
SubscriptionItem "*" --> "1" RatePlan
Subscription "1" o-- "*" Amendment
Charge --> ChargeType
Charge --> PricingModel
Amendment --> AmendmentType
@enduml