}
void onReadCell(XSSFCell cell){
//collect cells holding shared formulas
CTCell ct = cell.getCTCell();
CTCellFormula f = ct.getF();
if (f != null && f.getT() == STCellFormulaType.SHARED && f.isSetRef() && f.getStringValue() != null) {
// save a detached copy to avoid XmlValueDisconnectedException,
// this may happen when the master cell of a shared formula is changed
sharedFormulas.put((int)f.getSi(), (CTCellFormula)f.copy());
}
if (f != null && f.getT() == STCellFormulaType.ARRAY && f.getRef() != null) {
arrayFormulas.add(CellRangeAddress.valueOf(f.getRef()));
}
}