if (table instanceof DataTable) {
DataTable dataTable = (DataTable) table;
RowGrouping rowGrouping = dataTable.getRowGrouping();
if (rowGrouping != null) {
customRows.add(new GroupHeaderRow(dataTable));
customRows.add(new InGroupHeaderRow(dataTable));
customRows.add(new InGroupFooterRow(dataTable));
customRows.add(new GroupFooterRow(dataTable));
}
}