援引
Enhanced for
Loop - This new language construct eliminates the drudgery and error-proneness of iterators and index variables when iterating over collections and arrays.
用法
增强for循环代替了一些原来的for循环的使用,使语句含义上更合理
被遍历的表达式必须是数组类型或者实现了Iterable接口,循环变量前面除了可以加类型之外还可以加修饰符,例如final之类的
例子
1: public static void main(String[] args) {
2: // TODO Auto-generated method stub
3: ArrayList<String> al = new ArrayList<String>();
4: al.add("1");
5: al.add("2");
6: al.add("3");
7: for(String str : al){
8: System.out.println(str);
9: }
10:
11: int[] arr = new int[]{1,2,3};
12: for(int i : arr){
13: System.out.println(i);
14: }
15: }