class ClientMultiAxisGroupBy implements ClientGroupBy<ClientLevelAxis> {

    public Set<String> keySet() {
        Set<String> keys = new HashSet<String>();
        if (this.rows != null) {
            keys.add(ClientGroupAxisEnum.ROWS.toString());
        }
        if (this.columns != null) {
            keys.add(ClientGroupAxisEnum.COLUMNS.toString());
        }
        return keys;
    }

    public  ClientMultiAxisGroupBy();
    public  ClientMultiAxisGroupBy(ClientMultiAxisGroupBy source);

}