0. 总结(JDK1.5之前自定义枚举类)
- 1.声明(Season)对象的属性:private final修饰
- 2.私有化类的构造器,并给对象属性赋值
- 3.提供当前枚举类的多个对象:public static final的
- 4.其他诉求1:获取枚举类对象的属性
- 4.其他诉求2:提供toString()
1. 定义
(1)类的对象只有有限个,确定的,称为枚举类。如星期:Monday(星期一)、…、Sunday(星期天) , 性别:Man(男)、Woman(女)。
(2)当需要定义一组常量时,强烈建议使用枚举类。
(3)若枚举只有一个对象, 则可以作为一种单例模式的实现方式。
2. 如何自定义枚举类(JDK1.5之前自定义枚举类)
如:
public class SeasonTest {
public static void main(String[] args) {
Season spring = Season.SPRING;
System.out.println(spring);
}
}
//自定义枚举类
class Season{
//1.声明Season对象的属性:private final修饰
private final String seasonName;
private final String seasonDesc;
//2.私有化类的构造器,并给对象属性赋值
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:public static final的
public static final Season SPRING = new Season("春天","春暖花开");
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","冰天雪地");
//4.其他诉求1:获取枚举类对象的属性
public String getSeasonName() {
return seasonName;
}
public String getSeasonDesc() {
return seasonDesc;
}
//4.其他诉求1:提供toString()
@Override
public String toString() {
return "Season{" +
"seasonName='" + seasonName + '\'' +
", seasonDesc='" + seasonDesc + '\'' +
'}';
}
}