map排序

public class SortComparator
{  
    @SuppressWarnings("unchecked")
public static  ArrayList<Map.Entry<?, ?>> sortMap(Map<?,?> map)
{
List<Map.Entry<?, ?>> arrayList = new ArrayList<Map.Entry<?, ?>>(map.entrySet());
Collections.sort(arrayList, new Comparator()
{
public int compare(Object o1, Object o2)
      {  
           Map.Entry<?, ?> obj1 = (Map.Entry<?, ?>)o1;  
           Map.Entry<?, ?> obj2 = (Map.Entry<?, ?>)o2;           
            return obj1.getValue().toString().compareTo(obj2.getValue().toString()); 
      }
});
return (ArrayList<Entry<?, ?>>) arrayList;
}
}