Using an {@link InputStream} requires more memory than using a File, so if a {@link File} is available then you should instead do something like

       OPCPackage pkg = OPCPackage.open(path);
       XSSFWorkbook wb = new XSSFWorkbook(pkg);
       // work with the wb object
       ......
       pkg.close(); // gracefully closes the underlying zip file
   

Once you have finished working with the Workbook, you should close the package by calling {@link #close()}, to avoid leaving file handles open.

Opening a XSSFWorkbook from a file has a lower memory footprint than opening from an InputStream

Once you have finished working with the Workbook, you should close the package by calling either {@link #close()} or {@link OPCPackage#close()}, to avoid leaving file handles open.

Creating a XSSFWorkbook from a file-backed OPC Package has a lower memory footprint than an InputStream backed one.