Having trouble with java.lang.NoClassDefFoundError: java.security.acl.Group

[Michail Panagoulias]

Hello,

I am new to Java Spring and Keycloak integration so i tried to run some examples i found on github.

I can't manage to make any one that i tried work, even the ones published by keycloak.

Some have repository errors and the most give me the error mentioned on the title.

I can get access tokens from keycloak just fine but when i try to use the token to access a url in

my Spring app maven reports error java.lang.NoClassDefFoundError: java.security.acl.Group

at keycloak-spring-security.

The one project that is pretty much easy to setup and try to replicate the issue is the following:

https://github.com/ineat/spring-keycloak-tutorials

Please inform me on what information you need for my setup if needed.

Thank you very much in advance!

[Dennis Griese]

The error comes with OpenJDK 14. The class in your error message was removed from the JDK
but is still referenced by the keycloak adapter.
https://issues.redhat.com/browse/KEYCLOAK-13690

Try to use Java 13 and it should work without any problems.

[Michail Panagoulias]

Thank you very much for the heads up! That was it!