Even beyond the code, it is important to note that in a
J2EE application, the various ways of packaging an application, and the way in which classloaders work, even a class coded according to what you would find in a typical Design
Pattern Book, it is very possible that multiple instances of a singleton might be created.
I love profiling a WebSphere application, and showing the developers all of the various instances of their 'singleton' that is running. I never get tired of watching a well intentioned developer blush.
Cheers!
-Cameron McKenzie