Java Applet to manage file uploads to server

Question

Looking for a descent looking Java File Upload Applet (or even Flash) that fits the following requirements:

1. Free/cheap (yes looking to use in a commercial web application)
2. Preferably allow multiple file selection
3. Ability to create/edit folders on destination server? (within a secure root folder)
4. Ability to overwrite files in the destination directory?
5. IE + Firefox support required... Safari, Chrome, etc. a bonus
6. Ability to "hook" into the flow to apply additional logic

Notes:

• In particular I'm looking for the ability to upload to a directory on another server (e.g. not where my web server or app server is running)
• The destination server has a shared drive where all users of the app have permission to store files.
• By "decent looking" I'd really, really like to avoid a UI that is "skinned" like this:
  _{(source: swtguibuilder.com)}

Before I'm shut down for "not programming related" I would need to be able to hook into such an applet to apply some additional permission logic etc. I don't want to re-invent the wheel if someone else has made a component that already does what I need.

Answer 1

There at least two requirements:

1. Applet file uploader These are available, e.g.: http://sourceforge.net/projects/jupload/
2. Widget to configure destination This is unusual in my experience, but I wrote one once for a Swing app which would be similar for an applet. It was necessary to provide the user a view of the remote file system, enable manipulation of the view, and then upload the changes. Note that there are transactions issues here, so it's not trivial.

Answer 2

The simple answer to your question used to be Flash. Since the release of Flash Player 10 it isn't anymore. Adobe has added a restriction on File upload which only allows a file to be uploaded in the scope of UIA - User Initiated Action. This means that a file upload must be started with a mouse click.

There are some of free file uploaders built in flash available. The only problem is that the queuing is broken by FP10. Adding the files to the pending uploads list is no problem. Starting the upload is no problem either. But when one file upload is done and the next should begin, Flash Player will not allow it if you don't click again which is pretty much useless.

Answer 3

This is relatively easy with Java. Look into Apache Commons Fileupload for the server-side code. For the front-end, there are many examples of flash-based file uploads.