I'm a Java programmer who is working on an iPhone application. I'd like it to use Push Notification services.
I originally thought I could use Google App Engine to provide the payloads to Apple, but I see now that it won't be possible because App Engine doesn't support the low-level socket programming that is needed to communicate with Apple.
Are there any alternatives to Google App Engine that let me use Java?
In brief, I'm wondering if there is a free hosting platform that supports Java and Socket Programming
UPDATE - since writing this question I've written an app that uses Urban Airship to act as a middleman between GAE and APNS. It works just swell. There is an app engine issue on this - http://code.google.com/p/googleappengine/issues/detail?id=1164 if you'd like to follow, but personally I've decided that this isn't really something that GAE should be doing. Just use Urban Airship.
You can also check and follow these guys. It seems they are working on different stuff onto APNS integration. check out ns4app
Edit : They are changed their names and products ? forget my previous link. Check out MonoPush Project
You can do it yourself with an Amazon EC2 cluster. They have a nice Eclipse plugin for easily spawning Tomcat instances and remote debugging Java applications.
Though as yet it's vaporware, keep an eye on App Notify as well. Urban Airship looks pretty cool, but doing the math in my head, I'd end up paying them hundreds of dollars a month for an app that I'd have a hard time selling for more than $0.99.
Like Justin said (thanks random evangelist), AppNotify is launching nearer to the end of this month. We're just finishing up a few admin screens and doing some final tests. The pricing will be better structured than Urban Airship, and with a much better interface.
If you want something in particular or more info, send me an email personally at adam.m@selectstartstudios.com
We're using it to develop our own products, but if we've missed a corner case I'd like to know about it.
Good luck
Urban Airship provide RESTful web services for sending iPhone push notifications. This cookbook example shows how to use it from GAE using Python; I assume this can be done in Java also.