JAVA学习--枚举类的使用

* 一、枚举类
 * 1.如何自定义枚举类
 * 2.如何使用enum关键字定义枚举类
 *    
>常用的方法:values() valueOf(String name)
 *    
>如何让枚举类实现接口:可以让不同的枚举类的对象调用被重写的抽象方法，执行的效果不同。（相当于让每个对象重写抽象方法）

 1 //普通枚举类
 2 class Season{
 3     //1.提供类的属性，声明为private final
 4     private final String seasonName;
 5     private final String seasonDesc;
 6     //2.声明为final的属性，在构造器中初始化。
 7     private Season(String seasonName,String seasonDesc){
 8         this.seasonName = seasonName;
 9         this.seasonDesc = seasonDesc;
10     }
11     //3.通过公共的方法来调用属性
12     public String getSeasonName() {
13         return seasonName;
14     }
15     public String getSeasonDesc() {
16         return seasonDesc;
17     }
18     //4.创建枚举类的对象:将类的对象声明public static final
19     public static final Season SPRING = new Season("spring", "春暖花开");
20     public static final Season SUMMER = new Season("summer", "夏日炎炎");
21     public static final Season AUTUMN = new Season("autumn", "秋高气爽");
22     public static final Season WINTER = new Season("winter", "白雪皑皑");
23     @Override
24     public String toString() {
25         return "Season [seasonName=" + seasonName + ", seasonDesc="
26                 + seasonDesc + "]";
27     }
28     public void show(){
29         System.out.println("这是一个季节");
30     }
31 }

//自定义枚举类
interface Info{
    void show();
}
//枚举类
enum Season1 implements Info{
    SPRING("spring", "春暖花开"){
        public void show(){
            System.out.println("春天在哪里？");
        }
    },
    SUMMER("summer", "夏日炎炎"){
        public void show(){
            System.out.println("生如夏花");
        }
    },
    AUTUMN("autumn", "秋高气爽"){
        public void show(){
            System.out.println("秋天是用来分手的季节");
        }
    },
    WINTER("winter", "白雪皑皑"){
        public void show(){
            System.out.println("冬天里的一把火");
        }
    };

    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;
    }

    @Override
    public String toString() {
        return "Season [seasonName=" + seasonName + ", seasonDesc="
                + seasonDesc + "]";
    }
//    public void show(){
//        System.out.println("这是一个季节");
//    }
}

    public static void main(String[] args) {
        Season1 spring = Season1.SPRING;
        System.out.println(spring);
        spring.show();
        System.out.println(spring.getSeasonName());

        System.out.println();
        //1.values()
        Season1[] seasons = Season1.values();
        for(int i = 0;i < seasons.length;i++){
            System.out.println(seasons[i]);
        }
        //2.valueOf(String name):要求传入的形参name是枚举类对象的名字。
        //否则，报java.lang.IllegalArgumentException异常
        String str = "WINTER";
        Season1 sea = Season1.valueOf(str);
        System.out.println(sea);
        System.out.println();

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

    }