code: public static <K> List<Map.Entry<K, Integer>> sortByIntegerValue(Map<K, Integer> map) {
          List<Map.Entry<K, Integer>> orderList = new ArrayList<>(map.entrySet());
          Collections.sort(orderList, new Comparator<Map.Entry<K, Integer>>() {
              @Override
              public int compare(Map.Entry<K, Integer> o1, Map.Entry<K, Integer> o2) {
                  return (o1.getValue() - o2.getValue());
              }
          });
          return orderList;
      }
docs: 根据MAP的VALUE进行排序，升序
  
  @param map
  @return