java for新循环_java新特性-新式for循环(For_Each)

package com.test.For_Each;

import java.util.ArrayList;

import java.util.Iterator;

import java.util.List;

public class ForTest

{

public static void main(String args[])

{

int arr[] = {1, 2, 3, 4, 5, 6, 7, 8};

/**

* 新式写法

*/

for (int a : arr)

System.out.println(a);

/**

* 旧式写法

*/

for (int i = 0; i < arr.length; i++)

System.out.println(arr[i]);

String arr2[] = {"好","流","哦","!!"};

for(String a2 : arr2)

System.out.println(a2);

int arr3[][] = {{1,2,3},{4,5,6,},{7,8,9}};

for(int a31[] : arr3)

{

for(int a32 : a31)

{

System.out.println(a32);

}

System.out.println();

}

List list = new ArrayList();

list.add("好");

list.add("流");

list.add("哦");

list.add("!!");

/**

* 根据集合类长度遍历

*/

for(int i=0;i

{

System.out.println(list.get(i));

}

/**

* 根据迭代器遍历

*/

for(Iterator i = list.iterator();i.hasNext();)

{

System.out.println(i.next());

}

/**

* 根据新式for-each遍历

*/

for(String element : list)

System.out.println(element);

}

}