转载：

Map
     
       map = new HashMap
      
       ();map.put("d", 2);map.put("c", 1);map.put("b", 1);map.put("a", 3);List
       
        
         > infoIds =    new ArrayList
         
          
           >(map.entrySet());//排序前for (int i = 0; i < infoIds.size(); i++) { String id = infoIds.get(i).toString(); System.out.println(id);}//d 2//c 1//b 1//a 3//排序Collections.sort(infoIds, new Comparator
           
            
             >() { public int compare(Map.Entry
             
               o1, Map.Entry
              
                o2) { //return (o2.getValue() - o1.getValue()); return (o1.getKey()).toString().compareTo(o2.getKey()); }}); //排序后for (int i = 0; i < infoIds.size(); i++) { String id = infoIds.get(i).toString(); System.out.println(id);}//根据key排序//a 3//b 1//c 1//d 2//根据value排序//a 3//d 2//b 1//c 1