Map 按值排序

最新推荐文章于 2024-09-01 11:33:01 发布

原创最新推荐文章于 2024-09-01 11:33:01 发布 · 95 阅读

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public static Map sortByValue(Map map) {
        List list = new LinkedList (map.entrySet());
        Collections .sort(list, new Comparator () {

            public int compare(Object o1, Object o2) {
                return ((Comparable ) ((Map .Entry) (o1)).getValue())
                        .compareTo(((Map .Entry) (o2)).getValue());
            }
        });
        Map result = new LinkedHashMap ();

        for (Iterator it = list.iterator(); it.hasNext();) {
            Map .Entry entry = (Map .Entry) it.next();
            result.put(entry.getKey(), entry.getValue());
        }
        return result;
    }

    public static Map sortByValue(Map map, final boolean reverse) {
        List list = new LinkedList (map.entrySet());
        Collections .sort(list, new Comparator () {

            public int compare(Object o1, Object o2) {
                if (reverse) {
                    return -((Comparable ) ((Map .Entry) (o1)).getValue())
                            .compareTo(((Map .Entry) (o2)).getValue());
                }
                return ((Comparable ) ((Map .Entry) (o1)).getValue())
                        .compareTo(((Map .Entry) (o2)).getValue());
            }
        });

        Map result = new LinkedHashMap ();
        for (Iterator it = list.iterator(); it.hasNext();) {
            Map .Entry entry = (Map .Entry) it.next();
            result.put(entry.getKey(), entry.getValue());
        }
        return result;
    }