I am attempting to write an event listener using the documentation. I have successfully compiled a basic jar with Maven with no errors. When I load it into guacamole, I get "Extension guac-listener.jar could not be loaded: Listener class cannot be loaded (wrong version of API?)".
My files are simple: guac-manifest.json: { "guacamoleVersion" : "1.5.5", "name" : "Guacamole Login Listener", "namespace" : "guac-listener", "listeners" : [ "org.apache.guacamole.event.LoginListener" ] } LoginListener.java: package org.apache.guacamole.event; import org.apache.guacamole.GuacamoleException; import org.apache.guacamole.net.event.listener.Listener; import java.io.FileWriter; import java.io.IOException; public class LoginListener implements Listener { @Override public void handleEvent(Object event) throws GuacamoleException { String path = "/tmp/dummy.txt"; String msg = "handler called!"; try (FileWriter writer = new FileWriter(path, true)) { writer.write(msg); } catch (IOException e) { System.out.println("Err"); } } } pom.xml dependencies: <dependencies> <dependency> <groupId>org.apache.guacamole</groupId> <artifactId>guacamole-ext</artifactId> <version>1.5.5</version> </dependency> </dependencies> My first guess is I am somehow linking the wrong library. The guacamole webserver is docker latest tag. Thanks Sent with [Proton Mail](https://proton.me/mail/home) secure email.