code: private void updateMonomerStore(MonomerStore monomerStore)
  			throws MonomerLoadingException, IOException, MonomerException, ChemistryException {
  		for (Monomer monomer : monomerStore.getAllMonomersList()) {
  			MonomerFactory.getInstance().getMonomerStore().addNewMonomer(monomer);
  			// save monomer db to local file after successful update //
  			MonomerFactory.getInstance().saveMonomerCache();
  		}
  	}
docs: method to combine the new MonomerStore to the existing one, in case of
  xHELM as input
  
  @param monomerStore
  MonomerStore
  @throws MonomerLoadingException
  if the monomer store can not be read
  @throws IOException
  if the monomer store can not be read
  @throws MonomerException
  if the monomer is not valid
  @throws ChemistryException
  if the chemistry can not be initialized