枚举类

enum常用方法

1. toString：Enum已经重写，返回当前对象名，子类可以重写该方法，用于返回对象的属性信息。
2. name：返回当前对象名（常量名），子类中不能重写。
3. ordinal：返回当前对象的下标。
4. values：返回当前枚举类中的所有常量。
5. valueOf：将字符串转换为枚举对象，要求字符串必须为已有的常量名，否则报错
6. compaperTo：比较两个枚举常量，比较的是下标。返回值为下标差。

sout(Season2.AUTUMN.compaperTo(Season2.SUMMER));

使用细节

1. enum已经默认继承Enum类，不能再继承其他类
2. 可以实现接口

为public static final类型的
class Season {
    private final String seasonName;
    private final String SeasonDesc;

    private Season(String seasonName, String seasonDesc) {
        this.seasonName = seasonName;
        this.SeasonDesc = seasonDesc;
    }
    // 提供当前枚举类的多个对象。必须声明为public static final
    public static final Season SPRING = new Season("春天", "春意盎然");
    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");

    public String getSeasonName() {
        return seasonName;
    }

    public String getSeasonDesc() {
        return SeasonDesc;
    }

    @Override
    public String toString() {
        return "Season{" +
                "seasonName='" + seasonName + '\'' +
                ", SeasonDesc='" + SeasonDesc + '\'' +
                '}';
    }
}
public class SeasonTest {
    public static void main(String[] args) {
        Season autumn = Season.AUTUMN;
        System.out.println(autumn);
    }
}