sortHashMapAscendingByValue.java

private HashMap<Integer, Integer> sortByValueAscending(HashMap<Integer, Integer> numCounts) {
        List<Map.Entry<Integer, Integer> > list = 
            new LinkedList<Map.Entry<Integer, Integer> >(numCounts.entrySet());
        
        Collections.sort(list, new Comparator<Map.Entry<Integer, Integer> >() {
            public int compare(Map.Entry<Integer, Integer> o1,
                               Map.Entry<Integer, Integer> o2)
            {
                return (o1.getValue()).compareTo(o2.getValue());
            }
        });
        
        HashMap<Integer, Integer> temp = new LinkedHashMap<Integer, Integer>();
        for (Map.Entry<Integer, Integer> aa : list) {
            temp.put(aa.getKey(), aa.getValue());
        }
        
        return temp;
    }