@Test
public void testSortMapByValueInDecendingOrder() {

    Map<Integer, Double> map = new TreeMap<Integer, Double>();
    map.put(1, 3.0);
    map.put(2, 2.0);
    map.put(3, 1.0);
    map.put(4, 4.0);
    Map<Integer, Double> expResult = new TreeMap<Integer, Double>();
    expResult.put(4, 4.0);
    expResult.put(1, 3.0);
    expResult.put(2, 2.0);
    expResult.put(3, 1.0);
    Map<Integer, Double> result = ChemicalFilters.sortMapByValueInDecendingOrder(map);
    assertEquals(expResult, result);
}