This project illustrates how to use the Java client AMQP library to access CloudAMQP from Heroku.
It consists of one worker which listens to a queue and prints the messages to the console (and thus to the Heroku log), and a "oneoff" process which enqeues messages to that queue.
For more information on AMQP and how to use it from Java, see RabbitMQ's tutorial.
Click this button to deploy the sample code to a new app on Heroku for free:
Make sure you have the Heroku Toolbelt installed. Scale the worker process, start the one-off process that enqueues messages and then inspect the log:
$ heroku ps:scale worker=1 -a your-app-name
$ heroku run "sh target/bin/oneoff" -a your-app-name
Running sh target/bin/oneoff attached to terminal... up, run.1
[x] Sent 'Hello CloudAMQP!'
$ heroku logs -a your-app-name
2012-03-28T16:59:59+00:00 app[worker.1]: [*] Waiting for messages
2012-03-28T17:02:34+00:00 heroku[api]: Scale to worker=1 by carl.hoerberg@gmail.com
2012-03-28T17:03:05+00:00 heroku[run.1]: State changed from created to starting
2012-03-28T17:03:06+00:00 app[run.1]: Awaiting client
2012-03-28T17:03:06+00:00 app[run.1]: Starting process with command `sh target/bin/oneoff`
2012-03-28T17:03:06+00:00 heroku[run.1]: State changed from starting to up
2012-03-28T17:03:07+00:00 app[worker.1]: [x] Received 'Hello CloudAMQP!'
2012-03-28T17:03:08+00:00 heroku[run.1]: Process exited with status 0
2012-03-28T17:03:08+00:00 heroku[run.1]: State changed from up to complete