@Test
public void testAxialEncoder_Empty() throws Exception {

    IAtomContainer container = mock(IAtomContainer.class);
    IAtom start = mock(IAtom.class);
    IAtom end = mock(IAtom.class);
    when(container.getConnectedBondsList(start)).thenReturn(Collections.<IBond> emptyList());
    when(container.getConnectedBondsList(end)).thenReturn(Collections.<IBond> emptyList());
    assertNull(GeometricCumulativeDoubleBondFactory.axialEncoder(container, start, end));
}