ValueComparator

public class Test {

    public static void main(String[] args) {

        Map<Long,Double> map = new LinkedHashMap<Long, Double>();
        map.put(1L, 3.0);
        map.put(2L, 1.0);
        map.put(3L, 4.0);
        map.put(4L, 2.0);

        List<Map.Entry<Long, Double>> entriesOld = new ArrayList<Map.Entry<Long, Double>>(map.entrySet());
        Collections.sort(entriesOld, new Old.ValueComparator());
        // entriesOld = [3=4.0, 1=3.0, 4=2.0, 2=1.0]
        System.out.println("entriesOld = " + entriesOld);

        List<Map.Entry<Long, Double>> entriesNew = new ArrayList<Map.Entry<Long, Double>>(map.entrySet());
        Collections.sort(entriesNew, new New.ValueComparator());
        // entriesNew = [3=4.0, 1=3.0, 4=2.0, 2=1.0]
        System.out.println("entriesNew = " + entriesNew);

        Assert.assertEquals(entriesNew, entriesOld); // ok
    }

    // Implementation before
    public static class Old {
        public static class ValueComparator implements Comparator{

            public ValueComparator() {
            }

            public int compare(Object a, Object b) {
                if( (Double)(((Map.Entry)(a)).getValue()) < ((Double)((Map.Entry) (b)).getValue()) ) {
                    return 1;
                } else if((Double)(((Map.Entry)(a)).getValue()) == (Double)(((Map.Entry)(b)).getValue())) {
                    return 0;
                } else {
                    return -1;
                }
            }
        }
    }

    // Implementation after
    public static class New {
        public static class ValueComparator implements Comparator<Map.Entry<Long, Double>> {
            public int compare(Map.Entry<Long, Double> a, Map.Entry<Long, Double> b) {
                return Double.compare(b.getValue(), a.getValue());
            }
        }
    }
}