java中的Iterator与增强for循环的效率比较

 1 　　public static void main(String[] args) {
 2         test();
 3     }
 4     
 5     public static void test() {
 6         
 7         List list = new ArrayList();
 8         int flag = 100000;
 9         int i=0;
10         while(i<flag) {
11             list.add(i);
12             i++;
13         }
14         
15         // iterator测试
16         long start = System.currentTimeMillis();
17             Iterator iterator = list.iterator();
18             while(iterator.hasNext()) {
19                 System.out.print(iterator.next());
20             }
21         long end = System.currentTimeMillis();
22         System.out.println("iterator本次执行耗费了"+(end-start)+"毫秒");
23         
24         // 增强for循环测试
25         long start2 = System.currentTimeMillis();
26             for(Integer inte : list) {
27                 System.out.print(inte);
28             }
29         long end2 = System.currentTimeMillis();
30         System.out.println("for本次执行耗费了"+(end2-start2)+"毫秒");
31     }