自定义枚举类

方式一：

　　注：jdk5.0以后不建议使用方式一来自定义枚举类，记录只是为了更好的理解。

/**
 * 方式一：jdk5.0之前，使用class自定义
 * 1：用private,final声明类的属性
 * 2：私有化构造器，并给属性赋值
 * 3:提供当前类有限个确定的对象，用public static final修饰
 */
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","春暖花开");
    public static final Season SUMMER = new Season("夏","夏日炎炎");
    public static final Season AUTUMN = new Season("秋","秋高气爽");
    public static final Season WINTER = new Season("冬","冬雪皑皑");

    public String getSeasonName() {
        return seasonName;
    }

    public String getSeasonDesc() {
        return seasonDesc;
    }

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

方式二：

　　注：jdk5.0之后switch支持枚举类型，case之后直接写枚举类的对象名就行，而不用枚举类.对象名

/**
 * 方式二：jdk5.0以后，使用enum关键字定义枚举类
 * 1：提供当前类有限个确定的对象
 * 2：用private,final声明类的属性
 * 3：私有化构造器，并给属性赋值
 * 说明:
 * 定义的枚举类默认继承java.lang.Enum,重写过toString
 * 可以让枚举类的对象分别实现接口的抽象方法
 */
enum SeasonEnum implements SeasonShow {
    SPRING("春","春暖花开") {
        @Override
        public void show() {
            System.out.println("春笋");
        }
    },
    SUMMER("夏","夏日炎炎") {
        @Override
        public void show() {
            System.out.println("夏蝉");
        }
    },
    AUTUMN("秋","秋高气爽") {
        @Override
        public void show() {
            System.out.println("秋雨");
        }
    },
    WINTER("冬","冬雪皑皑") {
        @Override
        public void show() {
            System.out.println("冬雪");
        }
    };

    private final String seasonName;
    private final String seasonDesc;

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

    public String getSeasonName() {
        return seasonName;
    }

    public String getSeasonDesc() {
        return seasonDesc;
    }
}

interface SeasonShow {
    void show();
}

枚举类的使用：

public class CustomerEnum {
    public static void main(String[] args) {
        Season autumn = Season.AUTUMN;
        SeasonEnum spring = SeasonEnum.SPRING;
        System.out.println(SeasonEnum.class.getSuperclass());
        //java.lang.Enum的常用方法
        System.out.println(spring.toString());
        System.out.println("**********************************");
        SeasonEnum[] values = SeasonEnum.values();
        for (SeasonEnum value : values) {
            System.out.println(value);
            value.show();
        }
        System.out.println("**********************************");
        SeasonEnum summer = SeasonEnum.valueOf("SUMMER");
        System.out.println(summer);
    }
}