java枚举enum

1.自定义枚举

// 自定义枚举  JDK5.0之前
public class enumTest {

    public static void main(String[] args) {
        Season Spring = Season.SPRING;
        System.out.println(Spring);
        Season Summer = Season.SUMMER;
        System.out.println(Summer);
        Season Autumn = Season.AUTUMN;
        System.out.println(Autumn);
        Season Winter = Season.WINTER;
        System.out.println(Winter);
    }

}



class Season{

    //1.声明Season对象的属性:private final修饰
    private final String season;
    private final String describe;

    //2.私有化类的构造器,并给对象属性赋值
    private Season(String season,String describe){
        this.season = season;
        this.describe = describe;
    }

    //3.提供当前枚举类的多个对象：public static final的
    public static final Season SPRING = new Season("春天","春暖花开");
    public static final Season SUMMER = new Season("夏天","夏日炎炎");
    public static final Season AUTUMN = new Season("秋天","秋高气爽");
    public static final Season WINTER = new Season("冬天","白雪皑皑");



    //4. 获取对象的属性
    public String getSeason() {
        return season;
    }

    public String getDescribe() {
        return describe;
    }


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

}

2. 使用enum类

public class enumTest1 {

    public static void main(String[] args) {

        Season1 s = Season1.SPRING;
        //方法1     toString():返回枚举类对象的名称  SPRING
        System.out.println(s.toString());
        System.out.println("----------------------------------");


        //方法2     values():返回所有的枚举类对象构成的数组
        Season1[] allSeason = Season1.values();
        for (int i = 0; i < allSeason.length; i++) {
            System.out.println(allSeason[i]);
        }


        System.out.println("----------------------------------");
        //方法3     valueOf(String objName):返回枚举类中对象名是objName的对象。
        Season1 summer = Season1.valueOf("SUMMER");
        System.out.println(summer.getDescribe());
        summer.show();
    }

}


interface Info{
    void show();
}


// 使用enum类  定义的枚举类默认继承于java.lang.Enum类


enum Season1 implements Info{   //实现接口

    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("宁夏");
        }
    },
    AUTUMN("秋天","秋高气爽"){
        @Override
        public void show() {
            System.out.println("秋天不回来");
        }
    },
    WINTER("冬天","白雪皑皑"){
        @Override
        public void show() {
            System.out.println("大约在冬季");
        }
    };


    private final String season;
    private final String describe;

    private Season1(String season,String describe){
        this.season = season;
        this.describe = describe;
    }


    public String getSeason() {
        return season;
    }

    public String getDescribe() {
        return describe;
    }


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