authenticatorConfig: Cannot configure an authenticator for method [KEYCLOAK]

I’m trying to secure a Vaadin 8 application with Keycloak by adding the following code to web.xml:




I also added a keycloak.json-file in the WEB-INF folder

    "realm": "my-realm",
    "auth-server-url": "http://localhost:8080/auth/",
    "resource": "my-resource",
     "public-client": true,
     "enable-basic-auth": true,
     "credentials" : {
       "secret" : "my-secret"

Context.xml in the META-INF

<?xml version="1.0" encoding="UTF-8"?>
 <Context path="/your-context-path">
    <Valve className="org.keycloak.adapters.tomcat.KeycloakAuthenticatorValve"/>

-> not sure what to fill in ‘path=’ though.

After that I put all the jars found in keycloak-tomcat-adapter-dist-10.0.1 in the apache-tomcat-8.5.55\lib directory. This should be enough to trigger a redirect to Keycloak, right? Problem is, when I deploy my application on Tomcat I get the error Cannot configure an authenticator for method [KEYCLOAK] which seems to indicate that I haven’t put the jars-files in the lib-directory of Tomcat, but I did. Am I missing something?