Java面向对象程序设计--泛型编程

 1 public class PairTest1 
 2 {
 3     public static void main(String[] args) 
 4     {
 5         String[] arr = {"This","is","the","end","of","the","world"};
 6         Pair<String> mm = ArrayAlg.minmax(arr);
 7         System.out.println("min = " + mm.getFirst());
 8         System.out.println("max = " + mm.getSecond());
 9     }
10 }
11 
12 class Pair<T>
13 {
14     public Pair() {first = null; second = null;}
15     public Pair(T first,T second) {this.first = first; this.second = second;}
16     
17     public T getFirst() {return first;}
18     public T getSecond() {return second;}
19 
20     public void setFirst(T newValue) {this.first = newValue;}
21     public void setSecond(T newValue) {this.second = newValue;}
22     
23     private T first;
24     private T second;
25 }
26 
27 class ArrayAlg
28 {
29     public static Pair<String> minmax(String[] a)
30     {
31         if(a == null || a.length == 0) return null;
32         String min = a[0];
33         String max = a[0];
34         for(int i = 1; i < a.length; i++)
35         {
36             if(min.compareTo(a[i]) > 0) min = a[i];
37             if(max.compareTo(a[i]) < 0) max = a[i];
38         }
39         return new Pair<String>(min,max);
40     }
41 }