//Set source for the pivot table
CTPivotCacheDefinition cacheDef = getPivotCacheDefinition().getCTPivotCacheDefinition();
CTCacheSource cacheSource = cacheDef.addNewCacheSource();
cacheSource.setType(STSourceType.WORKSHEET);
CTWorksheetSource worksheetSource = cacheSource.addNewWorksheetSource();
worksheetSource.setSheet(sourceSheet.getSheetName());
setDataSheet(sourceSheet);
String[] firstCell = source.getFirstCell().getCellRefParts();
String[] lastCell = source.getLastCell().getCellRefParts();
worksheetSource.setRef(firstCell[2]+firstCell[1]+':'+lastCell[2]+lastCell[1]);
}