code: @Override
      public Mappings matchAll(IAtomContainer mol) {
          if (mol.getAtomCount() < query.getAtomCount())
              return new Mappings(query, mol, Collections.<int[]>emptySet());
          if (mol.getAtomCount() > 0)
              checkCompatibleAPI(mol.getAtom(0));
          DfState local = new DfState(state);
          local.setMol(mol);
          return filter(new Mappings(query, mol, local), query, mol);
      }
docs: {@inheritDoc}