较复杂的枚举类型

package dataStyle;
 2  /**
 3  * 较复杂的枚举类型
 4  * @author ZolRa
 5  *
 6  */
 7  public class ComEnum {
 8     
 9     public static void main(String[] args) {
10         WeekDay weekDay = WeekDay.FRI;
11         System.out.println(weekDay.nextDay());
12     }
13     
14     public enum WeekDay{
15         //调用带参构造方法，匿名子类重写nextDay()方法
16         SUN(1){
17             public WeekDay nextDay() {
18                 return MON;
19             }
20         },
21         MON(2){
22             public WeekDay nextDay() {
23                 return TUE;
24             }
25         },
26         TUE(3){
27             public WeekDay nextDay() {
28                 return WED;
29             }
30         },
31         WED(4){
32             public WeekDay nextDay() {
33                 return THU;
34             }
35         },
36         THU(5){
37             public WeekDay nextDay() {
38                 return FRI;
39             }
40         },
41         FRI(6){
42             public WeekDay nextDay() {
43                 return SAT;
44             }
45         },
46         SAT(7){
47             public WeekDay nextDay() {
48                 return SUN;
49             }
50         };
51         
52         //星期索引，星期日为第一天
53         private int index;
54         //Constructor，必须为private
55         private WeekDay(){}         
57         private WeekDay(int index){
58             this.index = index;
59         }
60         
61         //获取下一天
62         public abstract WeekDay nextDay();
63         
64         public String toString() {
65             StringBuffer week = new StringBuffer();
66             switch (index) {
67             case 1:    week.append("星期日");break;
68             case 2:    week.append("星期一");break;
69             case 3:    week.append("星期二");break;
70             case 4:    week.append("星期三");break;
71             case 5:    week.append("星期四");break;
72             case 6:    week.append("星期五");break;
73             case 7:    week.append("星期六");break;
74             }
75             return week.toString();
76         }      
77     }     
78 }

打印：星期六