How to password protect a zipped Excel file in Java?

Question

I have a question about password protecting an Excel file.

The situation is that, I have a zip file, that has an Excel file in it. I need to write a Java program, to

Answer 1

• Use java.util.zip or zip4j to decompress file to some temp direcotry or to memory, if you know it's small.
• Then use HSSFWorkbook.writeProtectWorkbook from Apache POI library
• Compress Excel workbook again.