Process uploaded file content in Servlet and print the content in jsp

Question

First i must state that i'm jsp/servlet rookie trying to learn it's mechanisms.
INTRO:
Since i read this tutorial on using Apache-Commons-FileUpload 3.0, Servlet uploads .txt file successfully, and the file gets stored in Tomcat's wtpwebapps/MyProject/upload folder.
Here is the important part of UploadServlet's doPost method, it's just the same as in referenced tutorial:

try {
        // parses the request's content to extract file data
        List formItems = upload.parseRequest(request);
        Iterator iter = formItems.iterator();

        // iterates over form's fields
        while (iter.hasNext()) {
            FileItem item = (FileItem) iter.next();
            // processes only fields that are not form fields
            if (!item.isFormField()) {
                String fileName = new File(item.getName()).getName();
                String filePath = uploadPath + File.separator + fileName;
                File storeFile = new File(filePath);                     
                // saves the file on disk
                item.write(storeFile);
            }
        }
        request.setAttribute("message", "Upload has been done successfully!");
    } catch (Exception ex) {
        request.setAttribute("message", "There was an error: " + ex.getMessage());
    }
    getServletContext().getRequestDispatcher("/message.jsp").forward(request, response);
}

}

At the end of code segment, programmer specifies message text that will be printed in /messages.jsp file.

QUESTION:
Before setting the request attribute, how can i obtain an uploaded file as stream, do something with it line by line (using BufferedReader or similar), close the stream and send it as... String[] for example, to /message.jsp via container's request object?

Answer 1

FileItem has a getInputStream() method. Call it, read the file using the returned input stream, fill a List<String> with its contents, and add the list as an attribute to the request.