* @throws Exception
*/
public Calendar getStartOfOrder(Order order) throws Exception{
String xml = order.xml();
StringBuffer xmlBuf = new StringBuffer(xml);
SOSXMLXPath xp = new SOSXMLXPath(xmlBuf);
String startTime = xp.selectSingleNodeValue("/order/@start_time");
if (startTime==null || startTime.length()==0) {
throw new Exception("No start_time attribute was found for the current order");
}
Date dat = schedulerDateFormat.parse(startTime);
Calendar cal = Calendar.getInstance();