@Test
public void emptyAtomsListTest() {

    List<IAtom> atoms = new ArrayList<IAtom>();
    // switch on debugging, to see if NPE is thrown
    AtomPlacer placer = new AtomPlacer();
    boolean npeThrown = false;
    try {
        placer.populatePolygonCorners(atoms, new Point2d(0, 0), 0, 10, 10);
    } catch (NullPointerException npe) {
        npeThrown = true;
    }
    Assert.assertFalse("Null pointer for empty atoms list", npeThrown);
}