我试图通过执行以下循环来获取TreeMap的前10个元素：

        TreeMap<Integer, Integer> sortedMap = sortMap(m);
        String outString = "";
        int count = 10;
        while (count > 0) {
            count--;
            Integer k = sortedMap.firstKey();
            outString += String.valueOf(k);
            sortedMap.remove(k);
            if (count != 0) {
                outString += ",";
            }
        }

        System.out.println("outVal is " + outVal);

该打印outVal is 11377,11377,11377,11377,11377,11377,11377,11377,11377,11377
Integer工具Comparable，为什么可能remove不起作用？

更新 这是我的sortMap实现：

        public static TreeMap<Integer, Integer> sortMap(HashMap<Integer, Integer> map) {
           ValueComparator bvc =  new ValueComparator(map);
           TreeMap<Integer,Integer> sorted_map = new TreeMap<Integer,Integer>(bvc);
           sorted_map.putAll(map);
           return sorted_map;
        }

class ValueComparator implements Comparator<Integer> {
    java.util.Map<Integer, Integer> base;
    public ValueComparator(java.util.Map<Integer, Integer> base) {
        this.base = base;
    }

    // Note: this comparator imposes orderings that are inconsistent with equals.    
    public int compare(Integer a, Integer b) {
        if (base.get(a) >= base.get(b)) {
            return -1;
        } else {
            return 1;
        } // returning 0 would merge keys
    }
}

更新 这很有用：Java Map按值排序。