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/*
知识点：枚举
     枚举是从java5开始提供的一种新的数据类型，是一个特殊的类，就是多个常量对象的集合
定义格式：
     [修饰符] enum 枚举类名
     {
         常量A, 常量B, 常量C;
     }
 
*/
 
//定义枚举
enum Weekday
{
     Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday;
     //枚举类型中的Monday等价于原来的：public static final Weekday Monday = new Weekday();
}
 
class Employees
{
     private Weekday restday; //一周的哪一天休息（数据类型为Weekday）
 
     public Weekday getRestday()
     {
         return restday;
     }
 
     public void setRestday(Weekday restday) //数据类型为Weekday
     {
         this.restday = restday;
     }
}
 
public class EnumerateExample
{
     public static void main(String[] args) 
     {
         Employees e = new Employees(); //创建员工对象
         e.setRestday(Weekday.Wednesday); //通过类名.对象的方式来设置休息时间
         Weekday restday = e.getRestday(); //用Weekday类型的变量restday来接收得到的值
         
         if(restday == Weekday.Saturday || restday == Weekday.Sunday)
         {
             System.out.println("周末休息...");
         }
         else
         {
             System.out.println("周一至周五休息...");
         }
     }
}
 
/*
Weekday类的字节码文件内容（用java字节码反编译工具进行反编译后查看）：
 
final class Weekday extends Enum //自定义的Weekday枚举类在底层里都是继承java.lang中的Enum
{
 
     public static final Weekday Monday;
     public static final Weekday Tuesday;
     public static final Weekday Wednesday;
     public static final Weekday Thursday;
     public static final Weekday Friday;
     public static final Weekday Saturday;
     public static final Weekday Sunday;
     private static final Weekday $VALUES[];
 
     public static Weekday[] values()
     {
         return (Weekday[])$VALUES.clone();
     }
 
     public static Weekday valueOf(String s)
     {
         return (Weekday)Enum.valueOf(Weekday, s);
     }
 
     private Weekday(String s, int i)
     {
         super(s, i);
     }
 
     static 
     {
         Monday = new Weekday("Monday", 0);
         Tuesday = new Weekday("Tuesday", 1);
         Wednesday = new Weekday("Wednesday", 2);
         Thursday = new Weekday("Thursday", 3);
         Friday = new Weekday("Friday", 4);
         Saturday = new Weekday("Saturday", 5);
         Sunday = new Weekday("Sunday", 6);
         $VALUES = (new Weekday[] {
             Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday
         });
     }
}
*/