差点忘记List传的是引用

List<String> data = new ArrayList<String>();
		HashMap<String, List<String>> hashMap = new HashMap<String, List<String>>();
		hashMap.put("1", data);
		Log.i("test", "Hashmap size now is 1: " + hashMap.size());

		List<String> list = hashMap.get("1");
		Log.i("test", "List size must be 0:  " + list.size());

		data.add("8");
		data.add("9");
		Log.i("test", "List size :  " + list.size());

 

可以先把List放进Map中，再操作List,反正是传引用不是传值！