LonePair extends ElectronContainer implements Serializable, ILonePair, Cloneable { public LonePair() { this.atom = null; } LonePair();  LonePair(IAtom atom); @Override Integer getElectronCount(); @Override IAtom getAtom(); @Override void setAtom(IAtom atom); @Override boolean contains(IAtom atom); @Override Object clone(); @Override String toString();  }
@Test public void testLonePair() { ILonePair lp = new LonePair(); Assert.assertNull(lp.getAtom()); Assert.assertEquals(2, lp.getElectronCount().intValue()); }