java Map 转 List

public static void testMapVoid () {         Map map = new HashMap();         map.put("a", "a1");         map.put("b", "b1");         map.put("c", "c1");           List listKey = new ArrayList();         List listValue = new ArrayList();         Iterator it = map.keySet().iterator();         while (it.hasNext()) {             String key = it.next().toString();             listKey.add(key);             listValue.add(map.get(key));         }         System.out.println("Convert Finished !");                  for(int i =0 ;i<listKey.size();i++){             System.out.print("Key :"+listKey.get(i));             System.out.println("     Value :"+listValue.get(i));         }     }