Nullpointer Exception while copying archive to container (with Java 17)

[arnzel]

Nullpointer Exception while copying archive to container (with Java 17)

[arnzel]

Only occurs with Java 17. It works with Java 11

[dasniko]

Thanks for reporting.

I just tried to reproduce this behavior, but unfortunately I can't enforce the same exception.
When reading your posted stacktrace, this happens when actually trying to copy the extension into the container. This is done via default Testcontainers methods, no special or separate implementation from my side here.

The exception I get - and that's expected - is a UnsupportedClassVersionException during runtime/startup of the container. When the extension source is compiled with Java 17 and copied into the official default Keycloak container, which runs with Java 11, it won't work, of course.

[dasniko]

Closing this, as there was no further action in the last few months.