JRuby, Rails, and OC4J on OAS... oh the pain

Basic Rails app in version 2.3.4.

I kept running into errors like:

Error loading listener 'org.jruby.rack.rails.RailsServletContextListener', class not found

Setting up JDBC Resources became painful too. OAS, it seems, doesn't really care what you do after you first create your connection details. I kept testing my connection with changes to the settings and it kept running the test with the original information. To fix this, I had to delete the connection and recreate it.

I saw bugs pop up like:

09/09/11 15:56:05.734 dms: Servlet error
    java.lang.OutOfMemoryError: PermGen space
    09/09/11 15:56:07.998 dms: Servlet error
    java.lang.OutOfMemoryError: PermGen space
    09/09/15 11:09:21.756 dms: 10.1.3.4.0 Stopped
    09/09/15 11:09:22.325 Error in bean MBeanServerEjb: Error
    deserializing EJB-session 'MBeanServerEjb': null
    java.io.EOFException
      at java.io.ObjectInputStream$BlockDataInputStream.peekByte(ObjectInputStream.java:2502)

It turns out that I'm not alone in this experience. The difference in my case was that we were already giving a gigabyte of memory to our instance and we still saw this problem. So my habit became bouncing the OAS after a few deployments.