@Test
public void testHydrogens() throws CDKException {

    IAtomContainer container = new AtomContainer();
    container.addAtom(new Atom("H"));
    container.addAtom(new Atom("C"));
    container.addBond(0, 1, IBond.Order.SINGLE);
    container.addAtom(new Atom("H"));
    container.addBond(1, 2, IBond.Order.SINGLE);
    container.addAtom(new Atom("H"));
    container.addBond(1, 3, IBond.Order.SINGLE);
    container.addAtom(new Atom("H"));
    container.addBond(1, 4, IBond.Order.SINGLE);
    long[] numbers = InChINumbersTools.getNumbers(container);
    Assert.assertEquals(5, numbers.length);
    Assert.assertEquals(0, numbers[0]);
    Assert.assertEquals(1, numbers[1]);
    Assert.assertEquals(0, numbers[2]);
    Assert.assertEquals(0, numbers[3]);
    Assert.assertEquals(0, numbers[4]);
}