java - 如何创建没有实例变量的枚举类？

Question

我有一个带有枚举列表的类，枚举被传递给构造函数并更新为 toString，但我不允许在类上有实例变量(要求的一部分)。如何在不添加实例的情况下使枚举像字符串一样输出？

public enum Other {

    GAME_BOY("Game Boy"), MACBOOK("Macbook Pro"), IPHONE("iPhone XS"), LAPTOP("Laptop");

    private final String product; //can't have instance variable

    private Other(String passed) {
        this.product = passed;
    }

    @Override
    public String toString() {
        return product;
    }
}

Answer 1

您可以为每个元素覆盖 toString():

public enum Other {
   GAME_BOY {
     @Override public String toString() { return "Game Boy"; }
   },
   MACBOOK { ... },
   ...
}

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