JSP File
-------------
<form method="post" id="bulk-form" action="/pc/upload" enctype="multipart/form-data">
    <input type="hidden" name="product" value="${param.product}" />
    <input type="file" multiple name="fname">
    <input type="submit" class="btn red-btn" value="SUBMIT"/>
</form>
Servlet
-----------
String param = request.getParameter("product");
DiskFileItemFactory factory = new DiskFileItemFactory();
// Create a new file upload handler
ServletFileUpload upload = new ServletFileUpload(factory);
try {
    // Parse the request to get file items.
    List<FileItem> fileItems = upload.parseRequest(request);
    System.err.println("Got fileItems "+fileItems);
}
catch(Exception e){
}
In the above code the request.getParameter("product") returns the correct output but the fileItems is empty.
If hidden form is not used then request.getParameter("product") shows Connection terminated for multipart data.
