forEach与迭代器

任何实现了Iterable接口的类，都可以用forEach语句，并且Java中大部分的Collection都可以用forEach,除了Map
 1 import java.util.*;
 2 public class AdapterMethodiom implements Iterable<String>
 3 {
 4     protected String[] words = ("hello world this is a good day").split(" ");
 5     public Iterator<String> iterator() {
 6         return new Iterator<String>(){
 7             private int index =0;
 8 
 9             @Override
10             public boolean hasNext() {
11                 return index < words.length;
12             }
13 
14             @Override
15             public String next() {
16             
17                 return words[index++];
18             }
19             
20         };
21         
22     }
23     public static void main(String[] args) {
24         for(String s:new AdapterMethodiom())
25         {
26             System.out.println(s+" ");
27         }
28         
29     }
30 }