class ShardingResultSet extends AbstractResultSetAdapter {

    @Override
    public URL getURL(final int columnIndex) throws SQLException {
        Object result = mergeResultSet.getValue(columnIndex, URL.class);
        wasNull = null == result;
        return (URL) result;
    }

    public  ShardingResultSet(final List<ResultSet> resultSets, final ResultSetMerger mergeResultSet);

}