code: @Override
     protected int updateReference(String cid, int i, String refNodeIdentifier) throws SQLException,
        InvalidItemStateException, RepositoryException
     {
        if (updateReference == null)
        {
           updateReference = dbConnection.prepareStatement(UPDATE_REFERENCE);
        }
        else
        {
           updateReference.clearParameters();
        }
  
        updateReference.setString(1, refNodeIdentifier);
        updateReference.setString(2, cid);
        updateReference.setInt(3, i);
  
        return executeUpdate(updateReference, TYPE_UPDATE_REFERENCE);
     }
docs: {@inheritDoc}