code: public boolean couldMatchAtomType(IAtomContainer atomContainer, IAtom atom, IAtomType atomType) {
          logger.debug("   ... matching atom ", atom.getSymbol(), " vs ", atomType);
          if (atomContainer.getBondOrderSum(atom) + atom.getImplicitHydrogenCount() < atomType.getBondOrderSum()) {
              logger.debug("    Match!");
              return true;
          }
          logger.debug("    No Match");
          return false;
      }
docs: Determines if the atom can be of type AtomType.