RE: java.lang.AbstractMethodError: Receiver class org.apache.tomcat.websocket.server.WsSessionListener does not define or inherit an implementation

I think that I understand. I need to change Servlet API from 3.1 to 4.0. I was thinking that we can still use 3.1, and 4.0 would be compatible. https://tomcat.apache.org/whichversion.html Servlet SpecJSP SpecEL Spec WebSocket Spec Authentication (JASPIC) SpecApache Tomcat

Re: java.lang.AbstractMethodError: Receiver class org.apache.tomcat.websocket.server.WsSessionListener does not define or inherit an implementation

On Mon, Mar 20, 2023 at 1:59 PM Harri Pesonen wrote: > > Hello, > > I changed: > > * source code target from Java 8 to Java 11 > * Tomcat from 8.5 to 9.0.73 > * Java runtime from Java 11 to Java 17 > and now I see extra error in Tomcat log, which did not happen before: The Servlet