Can anyone explain the background/history of this annotation? Other than marking a parameter or return value to indicate that something can be null, is there any code that does something special with it at compile time?
Not as far as I am aware. It's intended as a user and developer "hint": any parameter or field *not* annotated with @Nullable is assumed to always be non-null. So you should never need to check it for null etc. in your code.
ap
