Java學習筆記---枚舉(enumeration)

枚舉可以有構做函數、字段和方法,去封裝更多信息

但是，注意：枚舉類的構造函數必須為私有的(private)
所以，下圖中沒用枚舉的Group類就用private重寫了構造函數



圖中兩個Group類都做到同樣的效果,但明顯用了枚舉的Group類簡潔很多吧？(笑)



然後，就是帶抽象方法的枚舉:
然後只要調用:
就會出現結果:


若枚舉類只有一個值，可以當作單態設計模式使用
就是這樣:

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