自定义枚举类与使用enum关键字定义枚举类

自定义枚举类

package com.joy.bean;

/*
* 如何手动创建枚举类
*
* ①声明Season对象的属性（用private final修饰）
* ②私有化类的构造器，并且给对象的属性赋值
* ③提供当前枚举类的多个对象（用public static final修饰）
* ------以下是可选步骤--------
* ④获取枚举类对象的属性
* ⑤重写Object类中的toString方法
* */
public class EnumOne {
    public static void main(String[] args) {
        Season spring = Season.SPRING;
        Season summer = Season.SUMMER;
        Season autumn = Season.AUTUMN;
        Season winter = Season.WINTER;
        //若未重写toString方法，又因为其继承的时Object类，则打印出的是地址值
        System.out.println(spring);
        System.out.println(summer);
        System.out.println(autumn);
        System.out.println(winter);
    }
}
class Season{
//  ①声明Season对象的属性（用private final修饰）
    private final String seasonName;
    private final String seasonDesc;
//  ②私有化类的构造器，并且给对象的属性赋值
    private Season(String seasonName,String seasonDesc){
        this.seasonName = seasonName;
        this.seasonDesc = seasonDesc;
    }
//  ③提供当前枚举类的多个对象（用public static final修饰）
    public static final Season SPRING = new Season("春","鸟语花香");
    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","白雪皑皑");
//  ④获取枚举类对象的属性
    public String getSeasonName(){
        return seasonName;
    }
    public String getSeasonDesc(){
        return seasonDesc;
    }
//  重写Object类中的toString方法，否则打印出的是地址值
    @Override
    public String toString() {
        return "季节："+seasonName+"  "+"描述："+seasonDesc;
    }
}
           

使用enum关键字定义枚举类

package com.joy.bean;

/*
 * 使用enum关键字定义枚举类
 *
 * ①提供当前枚举类的对象，多个对象之间用 ”,“ 隔开，最后用 ”;“ 结束
 * ②声明Season对象的属性（用private final修饰）
 * ③私有化类的构造器，并且给对象的属性赋值
 * ④获取枚举类对象的属性
 * ⑤重写Object类中的toString方法，否则打印出的是对象名
 *
 * 注意：第一步必须在最前面
 * */
public class EnumTwo {
    public static void main(String[] args) {
        Season2 spring = Season2.SPRING;
        Season2 summer = Season2.SUMMER;
        Season2 autumn = Season2.AUTUMN;
        Season2 winter = Season2.WINTER;
//      若未重写toString方法，又因为其继承的是Enum类，则打印出的是对象名
//      可由 System.out.println(Season2.class.getSuperclass());获取
        System.out.println(spring);
        System.out.println(summer);
        System.out.println(autumn);
        System.out.println(winter);
    }
}

enum Season2 {
//  ①提供当前枚举类的对象，多个对象之间用 ”,“ 隔开，最后用 ”;“ 结束

    SPRING("春", "鸟语花香"),
    SUMMER("夏", "夏日炎炎"),
    AUTUMN("秋", "秋高气爽"),
    WINTER("冬", "白雪皑皑");

//  ②声明Season对象的属性（用private final修饰）
    private final String seasonName;
    private final String seasonDesc;

//  ③私有化类的构造器，并且给对象的属性赋值
    private Season2(String seasonName, String seasonDesc) {
        this.seasonName = seasonName;
        this.seasonDesc = seasonDesc;
    }

//  ④获取枚举类对象的属性
    public String getSeasonName() {
        return seasonName;
    }

    public String getSeasonDesc() {
        return seasonDesc;
    }

//  ⑤重写Object类中的toString方法，否则打印出的是对象名
    @Override
    public String toString() {
        return "季节：" + seasonName + "  " + "描述：" + seasonDesc;
    }
}