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Java save xls file as PDF

I have a simple java program that creates .xls file (open office excel file), and I want to save it as pdf. I saw some answers here but none of them worked for me. Is there a simple and free way to do so?
The file contains only 1 page of .xls
Thanks

Not sure, please provide more details , share code so that the answer can be more precise, but for code perspective it can be achieved via Apache POI.something like below ....
//Instantiate a new workbook with excel file path
Workbook workbook = new Workbook("F:\\FileTemp\\Book1.xls");
//Save the document in Pdf format
workbook.save("F:\\FileTemp\\MyPdfFile.pdf", FileFormatType.PDF);

I have published a library that saves files, and handles everything with one line of code only, you can find it here along with its documentation
Github repository
and the answer to your question is so easy
String path = FileSaver
.get()
.save(fileXls,"file.pdf");

Automatically update database when new excel sheet is added in a folder

I need to write one java program which monitors a folder containing excel sheets (.xls format) . Once a new excel sheet is added I have to update the database in db2 and move the excel sheet to other place.
Please suggest

It sounds like you need to get notified if files appear in a directory. Java 7 has good support for this, see this article about the Watch Service API. The db2 part, well it isn't clear what you mean by "update", but likely you want to parse the content of the xls file and make some database updates. Apache POI is a good starting place for reading the content of the file into a Java process.

Is it possible using apache poi to load data from an open excel file that is constantly updating?

I have this Java program that uses apache poi to load data from an excel file.
Problem I'm facing is I can't seem to load data from the excel file that is constantly updating. I only get the initial data when I run my java program.

You have to reread the data from the excel file. POI makes a copy into java objects when it reads it, so any further changes won't get reflected in your Java code without rereading the file.
If you mean that you do reread the file but don't see the updates, then it could be that someone is making changes in excel but not saving them, so POI can't see them yet.

This Answer is referred from Fetch Data From Excel have a look at this answer for more details. Maybe this question is a duplicate of the above link or vice versa.
The problem is because the excel data is not saved. I was also dealing with the same problem and got up with a different solution which worked for me. I just created a macro in excel to save the excel workbook whenever it's cell values got changed. Now I got the excel file with up-to-date saved data which can be read through java code and can be used for other purposes.

Biff exception in Java

When I tried to read an Excel file in Java it throws "biff exception".
What does this mean? I tried to Google it but wasn't able to find a proper explanation.
jxl.read.biff.BiffException: Unable to recognize OLE stream
at jxl.read.biff.CompoundFile.<init>(CompoundFile.java:116)
at jxl.read.biff.File.<init>(File.java:127)
at jxl.Workbook.getWorkbook(Workbook.java:221)
at jxl.Workbook.getWorkbook(Workbook.java:198)
at Com.Parsing.ExcelFile.excel(Extract.java:20)
at Com.Parsing.Extract.main(Extract.java:55)

I also faced similar problem and was able to fix it.
I was using a .xlsx file and when I changed it to .xls file, it worked just fine. Seems JXL doesn't support .xlsx format.
Please correct me if somebody knows that it supports.

The javadoc for BiffException.
Exception thrown when reading a biff file.
This exception has a number of messages that should provide some information about the cause:
excelFileNotFound
excelFileTooBig
expectedGlobals
passwordProtected
streamNotFound
unrecognizedBiffVersion
unrecognizedOLEFile
Edit:
unrecognizedOLEFile seems to mean that something is embedded in the file that cannot be read.

An Excel workbook with several sheets (from BIFF5 on) is stored using the compound document file format (also known as “OLE2 storage file format” or “Microsoft Office compatible storage file format”). It contains several streams for different types of data.
A complete documentation of the format of compound document files can be found at
http://sc.openoffice.org/compdocfileformat.pdf
I think the exception mean that your parsing library can not recognise it(For example:biff5 format can not be parsed in POI and Jexcelapi).
You can check your file version be open it in Office and click 'SAVE AS',the format list in the filedialog is it's current file version.

Saving different csv files as different sheets in a single excel workbook

Related to this question, how to save many different csv files into one excel workbook with one sheet per csv ? I would like to know how to do this programmatically in Java.

You'll need some form of library for accessing Excel from Java. A Google search turned this one up:
http://j-integra.intrinsyc.com/support/com/doc/excel_example.html
An alternative is to use the XML Excel format that came into being with Office 2003. You'll end up with a XML file, but you can open it in Excel and see the different sheets.
http://www.javaworld.com/javaworld/jw-07-2004/jw-0712-officeml.html

If you want open source, the POI library can be used to generated Excel files.
A nice CSV parser is Open CSV
That should set the stage for what you are trying to do (basically use the CSV parser to get data, then write the data to an XLS file.

Take a look at the Aspose products, I've used them before when working with Excel and they saved me a huge amount of headache and time. Excel has several quirks that can make importing and exporting spreadsheets painful.
Aspose.Cells