【Map】MapTest

 1 package cn.itcast.p1.map.test;
 2 
 3 import java.util.HashMap;
 4 import java.util.Map;
 5 
 6 public class MapTest2 {
 7 
 8     public static void main(String[] args) {
 9         /*
10          * Map在有映射关系时，可以优先考虑。
11          * 
12          * 在查表法中的应用较为多见。
13          */
14         String week = getWeek(1);
15         
16         System.out.println(week);
17         
18         System.out.println(getWeekByMap(week));
19 
20     }
21 
22     public static String getWeekByMap(String week) {
23         Map<String,String> map = new HashMap<String,String>();
24         
25         map.put("星期一", "Mon");
26         map.put("星期二", "Tus");
27         map.put("星期三", "Wes");
28         map.put("星期日", "Sun");
29         
30         
31         return map.get(week);
32     }
33 
34     public static String getWeek(int i) {
35         if (i<1 || i>7)
36             throw new RuntimeException("没有对应的星期");
37         
38         String[] weeks = {"","星期一","星期二","星期三","星期四"};
39         
40         return weeks[i];
41     }
42 
43 }