JAVA---枚举类

package java0;

/**
 *一、枚举类的使用
 * 1.枚举类的理解：类的对象只有有限个，确定的，
 * 2.需要定义一组常量时，一般使用枚举类
 * 3.如果枚举类中只有一个实现对象，则可以作为单例模式的实现方式
 *
 * 二、如何定义枚举类
 * 方式一：JDK5.0之前，自定义枚举类
 * 方式二：JDK5.0，可以使用enum关键字定义枚举类
 *
 * 三、Enum类中常用方法
 *  1. values()方法：返回枚举类型的对象数组
 *  2. valueOf(String str):返回枚举对象名为str的对象，
 *  3. toString():返回当前枚举对象常量的名称
 *
 *  四、使用enum关键字定义的枚举类实现接口的情况
 *
 *  情况一：实现接口，在enum类中实现抽象方法
 *  情况二：让枚举类中的对象分别实现接口中的抽象方法
 *
 *
 *
 * @create 2022-03-23 17:53
 */
public class SeasonTest {
    public static void main(String[] args) {
        Season test=Season.SPRING;
        System.out.println(test);
    }
}

class Season{

    private final String seasonName;
    private final String seasonDesc;

    private Season(String seasonName,String seasonDesc){
        this.seasonName=seasonName;
        this.seasonDesc=seasonDesc;
    }


    public static final Season SPRING = new Season("春天","春暖花开");
    public static final Season SUMMER = new Season("夏天","夏天很热");
    public static final Season AUTUMN = new Season("秋天","秋高气爽");
    public static final Season WINTER = new Season("冬天","冬天很冷");

    public String getSeasonName() {
        return seasonName;
    }

    public String getSeasonDesc() {
        return seasonDesc;
    }

    @Override
    public String toString() {
        return "Season{" +
                "seasonName='" + seasonName + '\'' +
                ", seasonDesc='" + seasonDesc + '\'' +
                '}';
    }
}

---

package java0;

/**
 *使用enum关键字定义枚举类
 * 说明：定义的枚举类默认继承于java.lang.Enum类
 *
 *
 * @create 2022-03-24 11:12
 */
public class SeasonTest1 {

    public static void main(String[] args) {
        Season1 summer=Season1.SUMMER;

        System.out.println(summer.toString());

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

        Thread.State[] values1=Thread.State.values();
        for (int i = 0; i < values1.length; i++) {
            System.out.println(values1[i]);
        }

        Season1 winter=Season1.valueOf("WINTER");
        System.out.println(winter);
        winter.show();
    }
}
interface Info{
    void show();
}

enum Season1 implements Info{
    SPRING("春天","春暖花开"){
        @Override
        public void show() {
            System.out.println("春天春天");
        }
    },
    SUMMER("夏天","夏日炎炎"){
        @Override
        public void show() {
            System.out.println("夏天夏天");
        }
    },
    AUTUMN("秋天","秋高气爽"){
        @Override
        public void show() {
            System.out.println("秋天秋天");
        }
    },
    WINTER("冬天","冬天很冷"){
        @Override
        public void show() {
            System.out.println("冬天冬天");
        }
    };

    private final String seasonName;
    private final String seasonDesc;

    private Season1(String seasonName,String seasonDesc){
        this.seasonName=seasonName;
        this.seasonDesc=seasonDesc;
    }

    public String getSeasonName() {
        return seasonName;
    }

    public String getSeasonDesc() {
        return seasonDesc;
    }

}