TreeMap排序

参考
TreeMap 升序|降序排列

Map<String, Long> energyMap= new TreeMap<String, Long>();

List<Map.Entry<String, Double>> energyMapList = new ArrayList<Map.Entry<String, Double>>(energyMap.entrySet());
        Collections.sort(energyMapList, new Comparator<Map.Entry<String, Double>>() {
            @Override
            public int compare(Map.Entry<String, Double> o1, Map.Entry<String, Double> o2) {
                return o2.getValue().compareTo(o1.getValue());
            }
        });