Method used to order a Map<K, V extends Comparable>. Asked by @MxJesusDiaz at Twitter

MapOrderer.java

    /**
     * Orders a {@code Map<K, V>}
     * @param map The {@link Map} that will be ordered (The value types must extend {@link Comparable})
     * @param <K> The {@code K} value. Any type is supported
     * @param <V> The {@code V} value. Must extend {@link Comparable}
     * @return The sorted {@link Map} ordered by values with {@link Comparable#compareTo(Object)}
     * @author Hugmanrique <contact@hugmanrique.me>
     * @see {@link Collections#sort(List)} to order the values
     */
    public static <K, V extends Sort.Comparable> Map<K, V> orderMapByValues(Map<K, V> map){
        //Firstly, create a LinkedList to know with values go with each key
        List<Map.Entry<K, V>> list = new LinkedList<>(map.entrySet());

        //Sort the values in the List with a comparator
        Collections.sort(list, new Comparator<Map.Entry<K, V>>() {
            @Override
            public int compare(Map.Entry<K, V> o1, Map.Entry<K, V> o2) {
                //Let Java compare this automatically. Could do it manually returning -1, 0 or 1
                return (o1.getValue()).compareTo(o2.getValue());
            }
        });

        //The result Map (LinkedHashMap to conserve the order rather that by Object.hashCode())
        Map<K, V> result = new LinkedHashMap<>();

        //Fill the Map with the ordered values
        for (Map.Entry<K, V> entry : list){
            result.put(entry.getKey(), entry.getValue());
        }

        //Return the new map
        return result;
    }