對map 排序處理

public class Test {
   public static void main(String[] args) throws Exception{
  Map<String, Integer> map=new HashMap<String, Integer>();
  map.put("1", 1);
  map.put("9", 9);
  map.put("4", 4);
  map.put("2", 2);
  map.put("8", 8);
  map=mapSortByKey(map);
  System.out.println(map.toString());
     }

  private static SortedMap<String, Integer> mapSortByKey(Map<String, Integer> unsort_map) {
   TreeMap<String, Integer> result = new TreeMap<String, Integer>();

    Object[] unsort_key = unsort_map.keySet().toArray();
    //對key進行排序
    Arrays.sort(unsort_key);

    for (int i = 0; i < unsort_key.length; i++) {
     result.put(unsort_key[i].toString(), unsort_map.get(unsort_key[i]));
    }

    return result.tailMap(result.firstKey());
   }
}