Please Help, POI and Excel

[Dan]

Hello,

I am trying to read and write to an Excel file via my Java applet. I
have done so successfully on several simple Excel files that simply
had data cells without many complicated equations or any other Excel
extras. However, now is the time to get the complicated ones to work.
I didn't think that there would be a difference, but there is. At
first, I was beginning to think that it was a file size problem, but
now I am unsure. Does anyone know if there are any restrictions on
POI? How about some good reference info, asside from the java doc?

Here is some more info. Currently, the excel file is 6 sheets with
many complicated formulas as well as a few add ins including a fairly
complex solver. There will be more added to it later, which worries
me even more. It will also interact with some VB in the future.

However, I can not load the file at all. When I run the following
lines:

POIFSFileSystem fs = new POIFSFileSystem(new FileInputStream(file));
HSSFWorkbook wb = new HSSFWorkbook(fs, false);

I get the following exception on the second line:

[WARNING] Unknown Ptg 3c (60)
[WARNING] Unknown Ptg 3c (60)
[WARNING] Unknown Ptg 3c (60)
[WARNING] Unknown Ptg 3c (60)

java.lang.reflect.InvocationTargetException:
java.lang.ArrayIndexOutOfBoundsException
at org.apache.poi.util.LittleEndian.getNumber(LittleE ndian.java:557)
at org.apache.poi.util.LittleEndian.getShort(LittleEn dian.java:90)
at org.apache.poi.hssf.record.formula.NamePtg.<init>( NamePtg.java:100)
at org.apache.poi.hssf.record.formula.Ptg.createPtg(P tg.java:259)
at org.apache.poi.hssf.record.FormulaRecord.getParsed ExpressionTokens(FormulaRecord.java:171)
at org.apache.poi.hssf.record.FormulaRecord.fillField s(FormulaRecord.java:147)
at org.apache.poi.hssf.record.Record.fillFields(Recor d.java:143)
at org.apache.poi.hssf.record.Record.<init>(Record.ja va:105)
at org.apache.poi.hssf.record.FormulaRecord.<init>(Fo rmulaRecord.java:118)
at java.lang.reflect.Constructor.newInstance(Native Method)
at org.apache.poi.hssf.record.RecordFactory.createRec ord(RecordFactory.java:254)
at org.apache.poi.hssf.record.RecordFactory.createRec ords(RecordFactory.java:192)
at org.apache.poi.hssf.usermodel.HSSFWorkbook.<init>( HSSFWorkbook.java:191)
at scheduling.util.ExcelSheet.loadExcel(ExcelSheet.ja va:174)

I found the sheet that causes the problem, however I have no idea why.
When I delete all the cells in the sheet, it passes through this
part, but crashes further down the line. I tried deleting cells in
groups, trying to determine which cell or cells are causing the
problem, but it doesn't work because, in my opinion, the equations
rely on cells that I deleted.

Is there a way to run a debugger to determine where it is having a
problem? What about in the future, how will I be able to figure out
the next hurdle? There must be some good resources on this subject, I
just can't find any ... anyone know of any?

If you wish, please feel free to contact me via email at
zg***@planitusa.com. I have figured out how to use POI in a
relatively simple manner, but now I am at a loss. Please Help.

Dan

[Mark Voorberg]

Hi Dan,

I tried using the POI for a similar thing but ran into some serious
roadblocks regarding complex formulas.
The POI as it currently exists can only evaluate formulas that return
numeric values. There are other limitations on the POI site that are
clearly documented on their website.

If you really need to open a Micro$oft file, there's no better way than to
use a Micro$oft development environment.
Also consider that an applet cannot (without some security hassles) open
files on a file system other than where the applet was loaded from. So
unless your Excel file is on the webserver where a user will load the web
page containing the applet, you're out of luck. I have seen examples on the
microsoft site (and written some of my own) using JScript to manipulate
Excel file on the user's local workstation. I don't know your particular
requirements, but it may be an option.

Cheers,

Mark Voorberg
www.objectclarity.com

"Dan" <zh******@yahoo.com> wrote in message
news:75**************************@posting.google.c om...

Hello,

I am trying to read and write to an Excel file via my Java applet. I
have done so successfully on several simple Excel files that simply
had data cells without many complicated equations or any other Excel
extras. However, now is the time to get the complicated ones to work.
I didn't think that there would be a difference, but there is. At
first, I was beginning to think that it was a file size problem, but
now I am unsure. Does anyone know if there are any restrictions on
POI? How about some good reference info, asside from the java doc?

Here is some more info. Currently, the excel file is 6 sheets with
many complicated formulas as well as a few add ins including a fairly
complex solver. There will be more added to it later, which worries
me even more. It will also interact with some VB in the future.

However, I can not load the file at all. When I run the following
lines:

POIFSFileSystem fs = new POIFSFileSystem(new FileInputStream(file));
HSSFWorkbook wb = new HSSFWorkbook(fs, false);

I get the following exception on the second line:

[WARNING] Unknown Ptg 3c (60)
[WARNING] Unknown Ptg 3c (60)
[WARNING] Unknown Ptg 3c (60)
[WARNING] Unknown Ptg 3c (60)

java.lang.reflect.InvocationTargetException:
java.lang.ArrayIndexOutOfBoundsException
at org.apache.poi.util.LittleEndian.getNumber(LittleE ndian.java:557)
at org.apache.poi.util.LittleEndian.getShort(LittleEn dian.java:90)
at org.apache.poi.hssf.record.formula.NamePtg.<init>( NamePtg.java:100)
at org.apache.poi.hssf.record.formula.Ptg.createPtg(P tg.java:259)
at org.apache.poi.hssf.record.FormulaRecord.getParsed ExpressionTokens(FormulaRe
cord.java:171) at org.apache.poi.hssf.record.FormulaRecord.fillField s(FormulaRecord.java:147) at org.apache.poi.hssf.record.Record.fillFields(Recor d.java:143)
at org.apache.poi.hssf.record.Record.<init>(Record.ja va:105)
at org.apache.poi.hssf.record.FormulaRecord.<init>(Fo rmulaRecord.java:118)
at java.lang.reflect.Constructor.newInstance(Native Method)
at org.apache.poi.hssf.record.RecordFactory.createRec ord(RecordFactory.java:254
) at org.apache.poi.hssf.record.RecordFactory.createRec ords(RecordFactory.java:19
2) at org.apache.poi.hssf.usermodel.HSSFWorkbook.<init>( HSSFWorkbook.java:191) at scheduling.util.ExcelSheet.loadExcel(ExcelSheet.ja va:174)

I found the sheet that causes the problem, however I have no idea why.
When I delete all the cells in the sheet, it passes through this
part, but crashes further down the line. I tried deleting cells in
groups, trying to determine which cell or cells are causing the
problem, but it doesn't work because, in my opinion, the equations
rely on cells that I deleted.

Is there a way to run a debugger to determine where it is having a
problem? What about in the future, how will I be able to figure out
the next hurdle? There must be some good resources on this subject, I
just can't find any ... anyone know of any?

If you wish, please feel free to contact me via email at
zg***@planitusa.com. I have figured out how to use POI in a
relatively simple manner, but now I am at a loss. Please Help.

Dan