Map排序

Map<String,Integer> map = new HashMap<String, Integer>();
        map.put("语文", 90);
        map.put("数学", 91);
        map.put("地理", 88);
        map.put("物理", 99);
        map.put("化学", 78);
        map.put("生物", 60);
        map.put("外语", 80);
        
        for(Map.Entry<String,Integer> m : map.entrySet()){
            System.out.println(m.toString());
        }
        System.out.println("-----------排序后：---------");
        
        
        List<Map.Entry<String,Integer>> list = new ArrayList<Map.Entry<String,Integer>>(map.entrySet());
        Collections.sort(list,new Comparator<Map.Entry<String,Integer>>(){
            public int compare(Map.Entry<String,Integer> c1,Map.Entry<String,Integer> c2){
                return c2.getValue().compareTo(c1.getValue());
            }
        });
        
        for(int i=0;i<list.size();i++){
            String obj = list.get(i).toString();
            System.out.println(obj);
        }
        System.out.println("-----------平均分：---------");
        Integer count = 0;
        int n = 0;
        for(Map.Entry<String,Integer> m : map.entrySet()){
            Integer value = m.getValue();
            count = count+value;
            n++;
        }
        System.out.println(new DecimalFormat("#0").format(count/n));
        System.out.println("----------排名顺数第二的科目：----------");
        for(int i=0;i<list.size();i++){
            if(i == 1){
                Map.Entry<String,Integer> m = list.get(i);
                System.out.println(m.getKey());
            }
        }
        System.out.println("---------排名倒数第二的科目：-----------");
        for(int i=list.size()-1;i>=0;i--){
            if(i == list.size()-2){
                Map.Entry<String,Integer> m = list.get(i);
                System.out.println(m.getKey());
            }
        }