Setting factories throw null pointer exceptions during high load

1.) HookHotDeployListener uses the pattern XyzFactory.setInstance(null) to tell it to reset to the original implementation. But if another thread is calling XyzFactory.getInstance before the instance is reset to the original implementation, you get a null pointer excepton.

2.) Setting log level to DEBUG will do the same thing because it will try to call getClass().getName() on a null object.