steps to reproduce

1. load the attached file
2. export it as an Excel file

Actual result

java.lang.ArrayIndexOutOfBoundsException: -11353
at java.util.ArrayList.elementData(ArrayList.java:418)
at java.util.ArrayList.get(ArrayList.java:431)
at org.zkoss.poi.xssf.model.StylesTable.getCellStyleXfAt(StylesTable.java:340)
at org.zkoss.poi.xssf.usermodel.XSSFCellStyle.<init>(XSSFCellStyle.java:83)
at org.zkoss.poi.xssf.usermodel.XSSFNamedStyle.<init>(XSSFNamedStyle.java:54)
at org.zkoss.poi.xssf.usermodel.XSSFWorkbook.createNamedStyle(XSSFWorkbook.java:1954)
at org.zkoss.zss.range.impl.imexp.AbstractExcelExporter.toPOINamedStyle(AbstractExcelExporter.java:497)
at org.zkoss.zss.range.impl.imexp.AbstractExcelExporter.export(AbstractExcelExporter.java:116)
at org.zkoss.zss.api.impl.ExporterImpl.export(ExporterImpl.java:49)
at com.azquo.spreadsheet.controller.ZKSpreadsheetCommandController$1.process(ZKSpreadsheetCommandController.java:92)
at org.zkoss.zssex.ui.UpdateBridge.process(UpdateBridge.java:60)

Debug information

related code:

public class XSSFNamedStyle implements NamedStyle {


    private int _cellStyleXfId;

    private
	@Override
	public short getIndex() {
		return (short) _cellStyleXfId;
	}

The index is converted to a short and becomes a negative number, but it should be a 0-based integer.

workaround

• Do not import named styles. Then exported file content is also correct.