Java Map中按Value排序

1.方法

    // Map的value值降序排序
    public static <K, V extends Comparable<? super V>> Map<K, V> sortDescend(Map<K, V> map) {
        List<Map.Entry<K, V>> list = new ArrayList<>(map.entrySet());
        Collections.sort(list, new Comparator<Map.Entry<K, V>>() {
            @Override
            public int compare(Map.Entry<K, V> o1, Map.Entry<K, V> o2) {
                int compare = (o1.getValue()).compareTo(o2.getValue());
                return -compare;
            }
        });
 
        Map<K, V> returnMap = new LinkedHashMap<K, V>();
        for (Map.Entry<K, V> entry : list) {
            returnMap.put(entry.getKey(), entry.getValue());
        }
        return returnMap;
    }
 
    // Map的value值升序排序
    public static <K, V extends Comparable<? super V>> Map<K, V> sortAscend(Map<K, V> map) {
        List<Map.Entry<K, V>> list = new ArrayList<Map.Entry<K, V>>(map.entrySet());
        Collections.sort(list, new Comparator<Map.Entry<K, V>>() {
            @Override
            public int compare(Map.Entry<K, V> o1, Map.Entry<K, V> o2) {
                int compare = (o1.getValue()).compareTo(o2.getValue());
                return compare;
            }
        });
 
        Map<K, V> returnMap = new LinkedHashMap<K, V>();
        for (Map.Entry<K, V> entry : list) {
            returnMap.put(entry.getKey(), entry.getValue());
        }
        return returnMap;
    }

2.使用，Value支持全String或全數字

    map = sortDescend(map);// 降序排序
    System.out.println("降序后------------->" + map);

    map = sortAscend(map);// 升序排序
    System.out.println("升序后------------->" + map);