package com.lideng.work322; import java.util.HashMap; import java.util.HashSet; import java.util.Iterator; import java.util.Map; import java.util.Map.Entry; import java.util.Set; public class MapDome1 { /** * 利用增强for循环遍历集合 * @param args */ public static void main(String[] args) { HashMap<String, Integer> map=new HashMap<String, Integer>(); map.put("张三", 22); map.put("李四", 21); HashMap<String, Integer> map1=new HashMap<String, Integer>(); map1.put("王二", 20); map1.put("麻子", 26); Map<String, HashMap<String, Integer>> className=new HashMap<String, HashMap<String,Integer>>(); className.put("女", map); className.put("男", map1); //集合放到set里面 Set<Entry<String, HashMap<String, Integer>>> set=className.entrySet(); //遍历set里面的键 for (String entry : className.keySet()) { //遍历map里面的键 for ( String entry1 :className.get(entry).keySet()) { // key:entry1 value:className.get(entry).get(entry1) System.out.println("key :"+entry1+" value:"+className.get(entry).get(entry1)); } } } }