unable to run keytool after installing graalvm

[fs111]

I am learning asdf and asdf-java right now, so this may be obvious, but it is not to me.

I have installed graalvm like so:

asdf install java graalvm-21.1.0+java11

That worked fine. When I try to import a root certificate of my employer into the keystore via keytool I am getting this error message:

No version set for command keytool
Consider adding one of the following versions in your config file at
java graalvm-21.1.0+java11

It is unclear which config file it is talking about, at least to me.