Reinventing Smalltalk

What a cool idea! —

But ah-hah! We do, we can use a different implementation of FunctionTable which stores the method body as a String in Derby and uses BeanShell (or Janino!) to invoke it. So a method invocation is completely configurable at runtime! Not deploy time, runtime. If you find a bug, you can fix it without a redeploy.

Yes, Virginia, there is runtime update of objects in memory. What these two have come up with is the redefinition of object methods in a running system, no restart required. There's infrastructure to build to make it happen, but the principle is demonstrated. Java is catching up with Smalltalk bit by bit.