Create a password protected Excel file using Apache POI?

by

Updated: As of version 3.10 POI supports encryption as well as decryption for XLSX files. See the “Encryption Support” page on POI’s website. The below is still relevant for XLS binary workbooks.

According to the “Encryption Support” page on POI’s website POI supports reading encrypted XLS and XLSX files. Encrypting is not mentioned on that page, which implies that it’s not supported. This is backed up by searching the POI site for “encrypt” which returns only a handful of results all of which are about decryption. I’ve also taken a look at the sources for their crypto implementation, which appears to only handle decryption. This isn’t surprising; POI is designed for data extraction and search indexing, not for creating new spreadsheets.

As others have suggested, it’s often possible to work around missing features in POI by creating a template in Excel and then using POI to populate it with data. Unfortunately that won’t work for encryption because the file format of encrypted spreadsheets is radically different.

If you’re willing to pay for commercial software, the latest version of ExtenXLS has full read and write support for all the encryption formats supported by Excel. Just construct an EncryptedWorkBookHandle instead of the normal WorkBookHandle. That will use the strongest possible cipher supported by an unmodified JRE, RC4 for XLS and 128-bit AES for XLSX. If you want to use 256-bit AES with OOXML and you’ve installed the JCE unlimited policy you can do so with the MSOfficeEncrypter class.

JExcelAPI, a popular open-source Java spreadsheet API, does not appear to support encryption at all. Aspose.Cells, a commercial offering, supports stong encryption. The documentation for Actuate’s e.Spreadsheet seems to have disappeared from the ‘net, so I can’t tell whether it supports encryption or not.

Since none of the freely available Java spreadsheet APIs seems to support writing encrypted spreadsheets, if you’re not willing to use commercial software you’ll need to come up with a workaround. You could, for example, write the spreadsheet into an encrypted ZIP file. java.util.zip doesn’t support encryption, but it looks like Zip4j does.

Full disclosure: I work for Extentech, the company behind ExtenXLS.

More Related Contents:

  1. Converting JSON to XLS/CSV in Java [closed]
  2. How can I read numeric strings in Excel cells as string (not numbers)?
  3. Best language to parse extremely large Excel 2007 files [closed]
  4. How to read Excel cell having Date with Apache POI?
  5. Embed files into Excel using Apache POI
  6. Apache POI – FileInputStream works, File object fails (NullPointerException)
  7. Apache POI add a Series name into LineChart
  8. Apache poi Excel line chart points
  9. How to set axis’ labels in a Line Chart using Apache Poi
  10. Removing a row from an Excel sheet with Apache POI HSSF
  11. Apache POI autoSizeColumn Resizes Incorrectly
  12. What is the better API to Reading Excel sheets in java – JXL or Apache POI [closed]
  13. Merging cells in Excel using Apache POI
  14. Password Protected Excel File
  15. how to read exact cell content of excel file in apache POI
  16. Create Bar Chart in Excel with Apache POI
  17. Excel Cell Style issue
  18. How to insert a row between two rows in an existing excel with HSSF (Apache POI)
  19. Exception when writing to the xlsx document several times using apache poi 3.7
  20. Apache-POI sorting rows in excel
  21. Java POI : How to read Excel cell value and not the formula computing it?
  22. Apache POI evaluate formula
  23. Embed files into XSSF sheets in Excel, using Apache POI
  24. Apache POI Line Chart colors
  25. Java POI the supplied data appears to be in the Office 2007+ XML
  26. Determine MS Excel file type with Apache POI
  27. Make column read-only using apache poi
  28. Reading Specific rows of an excel [closed]
  29. How do I set cell value to Date and apply default Excel date format?
  30. Alternative to deprecated getCellType

Leave a Comment