map.clear list.clear

public static void main(String[] args){    List<String> aList = new ArrayList<String>();    aList.add("1");    aList.add("2");    aList.add("3");    Map<String,String> map = new HashMap<String, String>();    map.put("1", "1");    map.put("2", "2");    map.put("3", "3");    System.out.println("xxx"+aList.size());    System.out.println("xxx"+map.size());    aList.clear();    map.clear();    System.out.println("xxx"+aList.size());    System.out.println("xxx"+map.size());}