Homebrew install fails

[BalRoger]

Attempting to install mash on my MacBook:

$ brew install mdr/mash/mash
==> Tapping mdr/mash
Cloning into '/opt/homebrew/Library/Taps/mdr/homebrew-mash'...
remote: Enumerating objects: 52, done.
remote: Total 52 (delta 0), reused 0 (delta 0), pack-reused 52
Receiving objects: 100% (52/52), 5.29 KiB | 2.64 MiB/s, done.
Resolving deltas: 100% (16/16), done.
Tapped 1 formula (13 files, 11.7KB).
Error: mdr/mash/mash: Unsupported special dependency :java
$ 

I most DEFINITELY have Java installed, several OpenJDK versions, in fact. I'm a developer who programs in Java nearly daily.

I attempted to find help with this failure, but my Google-fu was weak.