Clean Code

類別圖：收銀機（策略模式)

Example: 收銀機

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@startuml Example-Cash-Register-Strategy-Pattern

class Program
{
  - CashContext cashContent
  + pay()
  + getReceipt()
}

class CashContext
{
  - Payable discountMethod
  - Receiptable receipt
  - resolveDiscountMethod()
  - resolveReceiptType()
  + pay()
  + getReceipt()
}

interface Payable
{
  + pay()
}

class NormalPay
{
  + pay()
}

class OffPercentPay
{
  + pay()
}

class FeedBackPay
{
  + pay()
}

interface Receiptable
{
  + getReceipt()
}

class ElectronicReceipt
{
  + getReceipt()
}

class NormalReceipt
{
  + getReceipt()
}

Payable <|.. NormalPay
Payable <|.. OffPercentPay
Payable <|.. FeedBackPay

Receiptable <|.. ElectronicReceipt
Receiptable <|.. NormalReceipt

Program -> CashContext
CashContext o-- Payable
CashContext o-- Receiptable

注意

  • Program 跟 CashContext 的方法名只是恰好與 Payable & Receiptable 中相同。
  • 為了易於理解，並未列出所有細節。

ʕ •ᴥ•ʔ：若不熟悉 UML 類別圖，可參考UML類別圖說明。

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