【Map】MapTest

 package cn.itcast.p1.map.test;

 import java.util.HashMap;
 import java.util.Map;

 public class MapTest2 {

     public static void main(String[] args) {
         /*
          * Map在有映射关系时，可以优先考虑。
          *
          * 在查表法中的应用较为多见。
          */
         String week = getWeek(1);

         System.out.println(week);

         System.out.println(getWeekByMap(week));

     }

     public static String getWeekByMap(String week) {
         Map<String,String> map = new HashMap<String,String>();

         map.put("星期一", "Mon");
         map.put("星期二", "Tus");
         map.put("星期三", "Wes");
         map.put("星期日", "Sun");

         return map.get(week);
     }

     public static String getWeek(int i) {
         if (i<1 || i>7)
             throw new RuntimeException("没有对应的星期");

         String[] weeks = {"","星期一","星期二","星期三","星期四"};

         return weeks[i];
     }

 }