【Java枚举类】使用enum关键词定义的枚举类实现接口

实现接口的枚举类

1.和普通 Java 类一样,枚举类可以实现一个或多个接口

2.若每个枚举值在调用实现的接口方法呈现相同的行为方式,则只要统一实现该方法即可。

3.若需要每个枚举值在调用实现的接口方法呈现出不同的行为方式,则可以让每个枚举值分别来实现该方法

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情况一:实现接口,在enum类中实现抽象方法
public class SeasonTest01 {
    public static void main(String[] args) {
        Season1 winter = Season1.valueOf("WINTER");
        System.out.println(winter);
        winter.show();
    }
}
interface Info{
    void show();
}
//使用enum关键词枚举类
enum Season1 implements Info{
    //1.提供当前枚举类的多个对象,多个对象之间用“,“隔开,末尾对象";"结束
    SPRING ("春天","春暖花开"),
    SUMMER ("夏天","夏日炎炎"),
    AUTUMN ("秋天","秋高气爽"),
    WINTER ("冬天","冰天雪地");


    //2.声明Season对象的属性:private final修饰
    private final String seasonName;
    private final String seasonDesc;

    //3.私有化类的构造器,并给对象属性赋值
    private Season1(String seasonName,String seasonDesc){
        this.seasonName = seasonName;
        this.seasonDesc = seasonDesc;
    }


    //4.其他诉求1:获取枚举类对象的属性
    public String getSeasonName() {
        return seasonName;
    }

    public String getSeasonDesc() {
        return seasonDesc;
    }

    @Override
    public void show() {
        System.out.println("这是一个季节");
    }

    //4.其他诉求1:提供toString()
//    @Override
//    public String toString() {
//        return "Season1{" +
//                "seasonName='" + seasonName + '\'' +
//                ", seasonDesc='" + seasonDesc + '\'' +
//                '}';
//    }
}

如果我们希望每一个对象调用的show()展现不一样的内容

情况二:让枚举类的对象分别实现接口中的抽象方法

public class SeasonTest01 {
    public static void main(String[] args) {
        Season1 summer = Season1.SUMMER;
        //toString():
        System.out.println(summer);

        //System.out.println(Season1.class.getSuperclass());

        System.out.println("===================================");
        //values():
        Season1[] values = Season1.values();
        for (int i = 0; i < values.length; i++) {
            System.out.println(values[i]);
            values[i].show();
        }

        System.out.println("=======================================");
        //valuesOf(String objName):返回枚举类中对象名是objName的对象
        //如果没有objName的枚举类对象,则抛异常:IllegalArgumentException
        Season1 winter = Season1.valueOf("WINTER");//WINTER1报错
        System.out.println(winter);
        winter.show();
    }
}
interface Info{
    void show();
}
//使用enum关键词枚举类
enum Season1 implements Info{
    //1.提供当前枚举类的多个对象,多个对象之间用“,“隔开,末尾对象";"结束
    SPRING ("春天","春暖花开"){
        @Override
        public void show() {
            System.out.println("春天在哪里");
        }
    },
    SUMMER ("夏天","夏日炎炎"){
        @Override
        public void show() {
            System.out.println("宁静的夏天");
        }
    },
    AUTUMN ("秋天","秋高气爽"){
        @Override
        public void show() {
            System.out.println("秋天不回来");
        }
    },
    WINTER ("冬天","冰天雪地"){
        @Override
        public void show() {
            System.out.println("大约在冬季");
        }
    };


    //2.声明Season对象的属性:private final修饰
    private final String seasonName;
    private final String seasonDesc;

    //3.私有化类的构造器,并给对象属性赋值
    private Season1(String seasonName,String seasonDesc){
        this.seasonName = seasonName;
        this.seasonDesc = seasonDesc;
    }


    //4.其他诉求1:获取枚举类对象的属性
    public String getSeasonName() {
        return seasonName;
    }

    public String getSeasonDesc() {
        return seasonDesc;
    }


    //4.其他诉求1:提供toString()
//    @Override
//    public String toString() {
//        return "Season1{" +
//                "seasonName='" + seasonName + '\'' +
//                ", seasonDesc='" + seasonDesc + '\'' +
//                '}';
//    }
}

运行结果如下:

感谢观看!!! 

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转载自blog.csdn.net/qq_64976935/article/details/129540991
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