Steps to Reproduce

1. import https://docs.google.com/spreadsheets/d/19bfzk8c4co1_l6EYuFcCxJyVTUoNw3HL/edit?usp=drive_link&ouid=114351817352708928223&rtpof=true&sd=true

Current Result

io.keikai.importer.ImportException: Fail to import cell A1 in sheet Account Summary from book 17025.xlsx
at io.keikai.importer.XlsxImporter.imports(XlsxImporter.java:331)
at io.keikai.range.impl.imexp.ExcelImportAdapter.imports(ExcelImportAdapter.java:50)
at io.keikai.range.impl.imexp.AbstractImporter.imports(AbstractImporter.java:57)
at io.keikai.ui.Spreadsheet.getSBook(Spreadsheet.java:737)
at io.keikai.ui.Spreadsheet.getSelectedSSheet(Spreadsheet.java:912)
at io.keikai.ui.Spreadsheet.doInvalidate(Spreadsheet.java:2884)
at io.keikai.ui.Spreadsheet.invalidate(Spreadsheet.java:2706)
at io.keikai.ui.Spreadsheet.setSrc(Spreadsheet.java:984)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at org.zkoss.zk.ui.metainfo.Property.assign0(Property.java:353)
at org.zkoss.zk.ui.metainfo.Property.assign(Property.java:186)
at org.zkoss.zk.ui.metainfo.ComponentInfo.applyProperties(ComponentInfo.java:743)
at org.zkoss.zk.ui.impl.AbstractUiFactory.newComponent(AbstractUiFactory.java:150)
at org.zkoss.zk.ui.impl.UiEngineImpl.execCreateChild0(UiEngineImpl.java:930)
at org.zkoss.zk.ui.impl.UiEngineImpl.execCreateChild(UiEngineImpl.java:900)
at org.zkoss.zk.ui.impl.UiEngineImpl.execCreate0(UiEngineImpl.java:787)
at org.zkoss.zk.ui.impl.UiEngineImpl.execCreate(UiEngineImpl.java:751)
at org.zkoss.zk.ui.impl.UiEngineImpl.execCreateChild0(UiEngineImpl.java:945)
at org.zkoss.zk.ui.impl.UiEngineImpl.execCreateChild(UiEngineImpl.java:900)
at org.zkoss.zk.ui.impl.UiEngineImpl.execCreate0(UiEngineImpl.java:787)
at org.zkoss.zk.ui.impl.UiEngineImpl.execCreateChild(UiEngineImpl.java:847)
at org.zkoss.zk.ui.impl.UiEngineImpl.execCreate0(UiEngineImpl.java:805)
at org.zkoss.zk.ui.impl.UiEngineImpl.execCreate(UiEngineImpl.java:751)
at org.zkoss.zk.ui.impl.UiEngineImpl.execNewPage0(UiEngineImpl.java:469)
at org.zkoss.zk.ui.impl.UiEngineImpl.execNewPage(UiEngineImpl.java:377)
at org.zkoss.zk.ui.http.DHtmlLayoutServlet.process(DHtmlLayoutServlet.java:253)
at org.zkoss.zk.ui.http.DHtmlLayoutServlet.doGet(DHtmlLayoutServlet.java:170)
...
Caused by: java.lang.NullPointerException: Cannot invoke "String.trim()" because "in" is null
at java.base/jdk.internal.math.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:1838)
at java.base/jdk.internal.math.FloatingDecimal.parseDouble(FloatingDecimal.java:110)
at java.base/java.lang.Double.parseDouble(Double.java:651)
at io.keikai.importer.XlsxImporter.importCell(XlsxImporter.java:1849)
at io.keikai.importer.XlsxImporter.importRow(XlsxImporter.java:1823)
at io.keikai.importer.XlsxImporter.imports(XlsxImporter.java:292)
... 69 more

Expected Result

no error, just treat A1 as empty cell

Debug Information

• the file to import is not produced by Excel.
• if you open the file in Excel and save it, the error doesn't happen anymore.