Android: Is there a component that can sync files with those on a web server?

Of course I could write it myself, but I'm wondering if anyone knows of an open-source android compo开发者_JS百科nent / example source code that will:

• Take a remote URL (http://www.example.com/foo.txt) and a local filename (/sdcard/ben/foo.txt)
• If the local file exists, check date/filesize etc, against the remote version by doing a HEAD request
• Download the file if missing or out of date

Cheers!

The android dropbox app does that, but afaik there is no component that does it. Maybe you can integrate dropbox via an intent. Otherwise you will have to roll your own.