Java-枚举类的两种实现方式

方法1：自定义实现枚举

package enum01;

/**
 * @author jee
 * @version 1.0
 */
public class Enum01 {
    public static void main(String[] args) {
        System.out.println(Season.SPRING);
        System.out.println(Season.SUMMER);
        System.out.println(Season.AUTUMN);
        System.out.println(Season.WINTER);

    }

}
//枚举
//枚举(enumeration/enum）
//枚举是一组常量集合
//可以这里理解：枚举属于一种特殊的类，里面只包含一组有限的特定的对象
//枚举的二种实现方式
//1.自定义类实现枚举
//2.使用enum关键字实现枚举

//演示自定义枚举实现
class Season{
    private String name;
    private String desc;
//    将构造器私有化
//    去掉setXXXX方法
//    在Season内部，直接创建固定对象
    public final static Season SPRING = new Season("春天","温暖");
    public final static Season SUMMER = new Season("夏天","炎热");
    public final static Season AUTUMN = new Season("秋天","凉爽");
    public final static Season WINTER = new Season("冬天","寒冷");
    private Season(String name,String desc)
    {
        this.name = name ;
        this.desc = desc ;

    }
    /**
    public void setName(String name)
    {
        this.name = name ;
    }

    public void setDesc(String desc)
    {
        this.desc = desc;
    }
      */
    public String getName()
    {
        return name;
    }
    public String getDesc()
    {
        return desc;
    }

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

方法2：使用enum关键字

package enum01;

/**
 * @author jee
 * @version 1.0
 */
public class Enum02 {
    public static void main(String[] args) {
        System.out.println(Season01.SPRING);
        System.out.println(Season01.SUMMER);
        System.out.println(Season01.AUTUMN);
        System.out.println(Season01.WINTER);
    }
}
//使用enum关键字来实现枚举类

/**
 * 总结：
 * 1.当我们使用enum关键字来开发一个枚举类时，默认会继承Enum类
 * 2.传统的public static final Season SPRING = new Season(“春天”，“温暖”),简化成了SPRING(“春天”，“温暖”)
 * 3.如果使用无参构造器创建枚举对象，则实参列表和小括号可以省略
 * 4.当有多个枚举对象时，使用逗号(,)分割，最后一个后面分号(;)结尾
 * 5.枚举对象必须放在枚举类的首行
 */
enum Season01{
    SPRING("春天","温暖"),SUMMER("夏天","炎热"),
    AUTUMN("秋天","凉爽"),WINTER("冬天","寒冷")
    ,MMM(),
    ;
    private String name;
    private String desc;
    private Season01()
    {

    }
    private Season01(String name,String desc)
    {
        this.desc = desc;
        this.name = name;
    }

    public String getDesc() {
        return desc;
    }

    public String getName() {
        return name;
    }

    @Override
    public String toString() {
        return "Season01{" +
                "name='" + name + '\'' +
                ", desc='" + desc + '\'' +
                '}';
    }
}