package cn.qyh.Collection; import java.util.ArrayList; import java.util.HashMap; import java.util.Iterator; import java.util.LinkedList; import java.util.List; import java.util.Map; public class TestIterator { public static void main(String[] args) { List<String> list = new ArrayList<String>(); list.add("张三1"); list.add("张三2"); list.add("张三3"); list.add("张三4"); List<String> list2 = new LinkedList<String>(); list2.add("李四1"); list2.add("李四2"); list2.add("李四3"); list2.add("李四4"); Map<Integer,String> map = new HashMap<Integer,String>(); map.put(001, "张三"); map.put(002, "李四"); map.put(003, "王五"); map.put(004, "赵六"); //list中用while遍历 Iterator<String> listIt = list.iterator(); while(listIt.hasNext()){ System.out.println(listIt.next()); } System.out.println("#############"); //用for遍历 for(Iterator<String> link = list2.iterator();link.hasNext();) { System.out.println(link.next()); } System.out.println("#############"); //Map分别获得key和value for(Integer key:map.keySet()) { //keyset获取key的值 System.out.println(key); } for(String value :map.values()) { //values获取value的值 System.out.println(value); } System.out.println("#############"); //Map中key和value一起获得 for(Map.Entry<Integer,String> entry:map.entrySet()) { //entry获取key和value System.out.println(entry.getKey()+":"+entry.getValue()); } System.out.println("#############"); //Iterator 和 entryset获取key和value Iterator <Map.Entry<Integer,String>> it = map.entrySet().iterator(); while(it.hasNext()) { Map.Entry<Integer, String> entry = it.next(); System.out.println(entry.getKey()+"---"+entry.getValue()); } } }