Java Map嵌套

import java.util.HashMap;

import java.util.Iterator;

import java.util.Map.Entry;

import java.util.Set;

public class MapMap {

public static void main(String[] args) {

// TODO Auto-generated method stub

HashMap<String, String> java=new HashMap<String,String>();

HashMap<String, String> web=new HashMap<String,String>();

java.put("j11111", "qqqqqq");

java.put("j22222", "wwwwww");

java.put("j33333", "eeeeee");

web.put("w111111", "aaaaaa");

web.put("w222222", "sssssss");

web.put("w333333", "ddddddd");

HashMap<String,HashMap<String, String>> ban=new HashMap<String,HashMap<String, String>>();

ban.put("java班", java);

ban.put("web班", web);

fun(ban);

}

//增强行 for 循环输出

public static void fun(HashMap<String,HashMap<String, String>> ban){

//输出班级

Set<Entry<String,HashMap<String, String>>> classnameSet=ban.entrySet();

for(Entry<String,HashMap<String, String>> i:classnameSet){

String classkey = i.getKey();

HashMap<String, String> classvalue = i.getValue();

System.out.println(classkey);

//输出学生

Set<Entry<String, String>> studentset=classvalue.entrySet();

for(Entry<String, String> a:studentset){

String key = a.getKey();

String value = a.getValue();

System.out.println(key+" "+value);

}

}

}

//迭代器

public static void fun(HashMap<String,HashMap<String, String>> ban){

Set<Entry<String,HashMap<String, String>>> classnameSet=ban.entrySet();

//班级

Iterator<Entry<String,HashMap<String, String>>> it=classnameSet.iterator();

while(it.hasNext()){

Entry<String, HashMap<String, String>> next=it.next();

String claString=next.getKey();

HashMap<String, String> classMap=next.getValue();

//输出班级

System.out.println(claString);

Set<Entry<String, String>> studentset=classMap.entrySet();

Iterator<Entry<String, String>> studentIt=studentset.iterator();

while (studentIt.hasNext()) {

Entry<String, String> studentEntry=studentIt.next();

String numkey=studentEntry.getValue();

String namevalue=studentEntry.getValue();

System.out.println(numkey+" "+namevalue);

}

}

}

}

}

}