枚举类

枚举类

• 简介



• 
  
• 不用枚举类的情况

package com.day0217_2;

public class MySeason {

    public static final int SPRING=0;
    public static final int SUMMER=1;
    public static final int AUTUMN=2;
    public static final int WINTER=3;

    public static void main(String[] args) {
        System.out.println(MySeason.AUTUMN);
    }

}

• 用枚举类的情况

package com.day0217_2;

import java.util.Random;

public class TestEnum {
    public static void main(String[] args) {
        System.out.println(Season.AUTUMN);//AUTUMN

        //枚举遍历
        for(Week k:Week.values()){//values()返回的：Week[] 里面包含了所有枚举元素
            System.out.println(k);
        }

        Week[] ws =Week.values();
        System.out.println(ws[0]);

        int a=new Random().nextInt(4);//0,1,2,3//(int)Math.Random()*4

        switch (Season.values()[a]){
            case SPRING:
                System.out.println("春天");
                break;
            case SUMMER:
                System.out.println("夏天");
                break;
            case AUTUMN:
                System.out.println("秋天");
                break;
            case WINTER:
                System.out.println("冬天");
                break;
        }

    }
}

enum Season{
    SPRING,SUMMER,AUTUMN,WINTER
}

enum Week{
    星期一,星期二,星期三,星期四,星期五,星期六,星期日
}