枚举--java24(02/17/2016)

如何自定义枚举类
如何使用enum定义枚举类、枚举类的主要方法
实现接口的枚举类

JDK1.5之前需要自定义枚举类
JDK1.5新增的enum关键字用于定义枚举类
若枚举只有一个成员，则可以作为一种单例模式的实现方式

枚举类对象的属性不应允许被改动，所以应该使用private final修饰。同时枚举类用private final修饰的属性应该在构造器中为其赋值。若枚举类显式的定义了带参数的构造器，则在列出枚举值时也必须对应的传入参数。

package com.atguigu.java1;
/*
 *  一、枚举类
 * 1.如何自定义枚举类
 */

public class TestSeason {

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

}
//枚举类
class Season{
    //1.提供类的属性，声明为private final
    private final String seasonName;
    private final String seasonDesc;
    //2.声明为final的属性，在构造器中初始化
    private Season(String seasonName, String seasonDesc){
        this.seasonName = seasonName;
        this.seasonDesc = seasonDesc;
    }
    //3.通过公共的方法来调用属性
    public String getSeasonName() {
        return seasonName;
    }
    public String getSeasonDesc() {
        return seasonDesc;
    }
    //4.创建枚举类的对象:将类的对象声明为public static final
    public static final Season SPRING = new Season("spring","春暖花开");
    public static final Season SUMMER = new Season("summer","夏日炎炎");
    public static final Season AUTOMN = new Season("automn","秋高气爽");
    public static final Season WINTER = new Season("winter","白雪皑皑");
    @Override
    public String toString() {
        return "Season [seasonName=" + seasonName + ", seasonDesc="
                + seasonDesc + "]";
    }
    
}