Hi, I know websocket 1.0 methods without providing the handler type are kind of deprecated (not recommended would be more correct) so not sure this bug would get a fix or not. Long story short, org.apache.tomcat.websocket.WsSession#addMessageHandler(jakarta.websocket.MessageHandler) will call Util.getMessageType which goes into the reflection code and the interesting part is org.apache.tomcat.websocket.Util#getGenericType and more precisely TypeResult superClassTypeResult = getGenericType(type, superClazz); which can return null (end of recursion) but next line being int dimension = superClassTypeResult.getDimension(); we can get a NPE.
The fix is trivial but I'mnot sure it is worth it or just redirecting to the right API would be better. Side note: for the context i'm using records instead of pojo, not very important since I guess interfaces would lead to the same issues but makes it more concrete. Romain Manni-Bucau @rmannibucau <https://twitter.com/rmannibucau> | Blog <https://rmannibucau.metawerx.net/> | Old Blog <http://rmannibucau.wordpress.com> | Github <https://github.com/rmannibucau> | LinkedIn <https://www.linkedin.com/in/rmannibucau> | Book <https://www.packtpub.com/application-development/java-ee-8-high-performance>
