JAVA : Exporting Data (from database) to excel and sending it to client side

Question

As the title suggest, I need to put some data (which I have got from database) into an excel sheet, and then send it to client side so that user can save , open or cancel th

Answer 1

You have two different copies of POI on your classpath, one old and one new. That's why you're getting the exception java.lang.IncompatibleClassChangeError: Class org.apache.poi.hssf.usermodel.HSSFWorkbook does not implement the requested interface org.apache.poi.ss.usermodel.Workbook - you've compiled against the new copy, but at runtime it's finding some new and some old jars.

This is covered in the POI FAQ. Ideally you should just be able to look at all the jars in your setup, and zap the old POI one. If not, the POI FAQ entry has some sample code you can use to get the JVM to print out where it has loaded POI classes from. That will show you the jar file name, and you can remove the old one.