### Question:
SingleMapping { protected synchronized List<Map<IAtom, IAtom>> getOverLaps( IAtomContainer source, IAtomContainer target) throws CDKException { List<Map<IAtom, IAtom>> mappings = new ArrayList<>(); this.source = source; this.target = target; if (source.getAtomCount() == 1 || (source.getAtomCount() > 0 && source.getBondCount() == 0)) { setSourceSingleAtomMap(mappings); } if (target.getAtomCount() == 1 || (target.getAtomCount() > 0 && target.getBondCount() == 0)) { setTargetSingleAtomMap(mappings); } return postFilter(mappings); } SingleMapping();   }### Answer:
@Test public void testGetOverLaps() throws CDKException { IAtom atomSource = new Atom("R"); IAtom atomTarget = new Atom("R"); IAtomContainer source = new AtomContainer(); source.addAtom(atomSource); IAtomContainer target = new AtomContainer(); target.addAtom(atomTarget); SingleMapping instance = new SingleMapping(); Assert.assertNotNull(instance.getOverLaps(source, target)); }