Close Filehandle for Workbook (apache poi)

If you need full control of when the resources get closed, you should create the OPCPackage yourself up front, and pass that into WorkbookFactory. OPCPackage provides the close method you're after. A Workbook will remain open until garbage collection.

Your code would look something like:

     File f = new File("/path/to/excel/file");
     Workbook wb = null;

     NPOIFSFileSystem npoifs = null;
     OPCPackage pkg = null;
     try {
       npoifs = new NPOIFSFileSystem(f);
       wb = WorkbookFactory.create(npoifs);
     } catch(OfficeXmlFileException ofe) {
       pkg = OPCPackage.open(f);
       wb = WorkbookFactory.create(pkg);
     }
  
     // Use it

     if (npoifs != null) { npoifs.close(); }
     if (pkg != null) { pkg.close(); }