public DrilldownTaskXmlDriver(String xmlStr) throws DocumentException,
            XmlTypeErrorException {
        super();
        if (!isDrilldownTaskXml(xmlStr)) {
            throw new XmlTypeErrorException("not a valid drilldownTask Xml");
        }
        document = DocumentHelper.parseText(xmlStr);
        timestamp = document.selectSingleNode("//properties/timestamp")
                .getText();
        fromCubeIdentifier = document.selectSingleNode(
                "//properties/operation/from").getText();

        Element root = this.document.getRootElement();
        List<?> list = root
                .selectNodes("//properties/operation/conditions/condition");
        String dimensionName;
        String levelName;
        final String start = "";
        final String end = "";
        ConditionBean conditionBean;
        for (Iterator<?> iter = list.iterator(); iter.hasNext(); ) {
            Node node = (Node) iter.next();
            dimensionName = node.selectSingleNode("dimensionName").getText();
            levelName = node.selectSingleNode("levelName").getText();
            conditionBean = new ConditionBean(dimensionName, levelName, start,
                    end);
            conditionBeans.add(conditionBean);
        }
    }