To be fair, the JVM predates GNU-style --long flags being "standard". Lots of older programs use "X11-style" -long flags (that many pre-X11 programs used, like `find`).

Long flags are a GNUism, not a "standard" by any means. The closest that comes to a standard in this space are POSIX utility conventions [1].

[1]: https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1...

I get it wrong every damn time. 16 years and counting.

Same! Somehow I also start confusing this with somewhat related tools like gcc. It's rare enough that I need to query these that it's all blurry in my memory again by next time. "huh I guess gcc was that goofy one with just one dash.." Nope.