Is there any reason for not using `define-derived-mode' when defining
`jde-mode'? (I see code that uses it is commented out.)
It turns out that not using it can have undesirable side-effects and
lead to "non-deterministic" behavior.
What happened to me recently is that the first Java file I opened during
my Emacs session was with `C-x C-f' from a Gnus *Group* buffer.
Consequently, `jde-mode-map' inherited Gnus bindings, which, needless to
say, is quite inconvenient. ;-)