@Override
    public void registerAuthenticationHandlerResolver(final AuthenticationHandlerResolver handlerResolver) {
        if (BeanSupplier.isNotProxy(handlerResolver)) {
            this.authenticationHandlerResolvers.add(handlerResolver);
        }
    }
This is {@link DefaultAuthenticationEventExecutionPlan}.

@author Misagh Moayyed
@since 5.1.0
core/cas-server-core-authentication-api/src/main/java/org/apereo/cas/authentication/DefaultAuthenticationEventExecutionPlan.java