* @return the URL for the report download
* @throws RemoteException if there was an error performing any Axis call
* @throws IllegalStateException if the report is not ready to be downloaded
*/
private String getDownloadUrl(ExportFormat exportFormat) throws RemoteException {
ReportJobStatus status = reportService.getReportJob(reportJobId).getReportJobStatus();
if (status != ReportJobStatus.COMPLETED) {
throw new IllegalStateException("Report " + reportJobId
+ " must be completed before downloading. It is currently: " + status);
}