集合套集合
import java.util.*; public class Practice_1 { public static <K, V> void main(String[] args) { HashMap<Integer,String> hm = new HashMap<Integer,String>(); hm.put(101,"java001"); hm.put(102,"java002"); hm.put(103,"java003"); hm.put(104,"java004"); HashMap<Integer,String> hh = new HashMap<Integer,String>(); hh.put(101,"python001"); hh.put(102,"python002"); hh.put(103,"python003"); hh.put(104,"python004"); HashMap<String,HashMap<Integer,String>> qq = new HashMap<String,HashMap<Integer,String>>(); qq.put("gaoxiaoban",hm); qq.put("shaonianban",hh); Set<String> keySet = qq.keySet(); Iterator<String> it = keySet.iterator(); while(it.hasNext()) { String s = it.next(); sop(s); sop(qq.get(s)); } } public static void sop(Object obj) { System.out.println(obj); } } /* 需求: 现在有一个大学校, 大学校里面有两个班, 每个班级对应班级里面的学号和行营 班级1 : gaoxiaoban 班级2 :shaonianban 特殊的: 班级的人员 */
作者:张小龙 一个不安定的程序猿