@SuppressWarnings({"CyclomaticComplexity"})
    @Override
    public void process(ApplicationEvent event) {
        switch (event.type()) {
            case COMMIT_ASYNC:
                process((AsyncCommitEvent) event);
                return;

            case COMMIT_SYNC:
                process((SyncCommitEvent) event);
                return;

            case POLL:
                process((PollEvent) event);
                return;

            case FETCH_COMMITTED_OFFSETS:
                process((FetchCommittedOffsetsEvent) event);
                return;

            case NEW_TOPICS_METADATA_UPDATE:
                process((NewTopicsMetadataUpdateRequestEvent) event);
                return;

            case ASSIGNMENT_CHANGE:
                process((AssignmentChangeEvent) event);
                return;

            case TOPIC_METADATA:
                process((TopicMetadataEvent) event);
                return;

            case ALL_TOPICS_METADATA:
                process((AllTopicsMetadataEvent) event);
                return;

            case LIST_OFFSETS:
                process((ListOffsetsEvent) event);
                return;

            case RESET_POSITIONS:
                process((ResetPositionsEvent) event);
                return;

            case VALIDATE_POSITIONS:
                process((ValidatePositionsEvent) event);
                return;

            case SUBSCRIPTION_CHANGE:
                process((SubscriptionChangeEvent) event);
                return;

            case UNSUBSCRIBE:
                process((UnsubscribeEvent) event);
                return;

            case CONSUMER_REBALANCE_LISTENER_CALLBACK_COMPLETED:
                process((ConsumerRebalanceListenerCallbackCompletedEvent) event);
                return;

            case COMMIT_ON_CLOSE:
                process((CommitOnCloseEvent) event);
                return;

            case SHARE_FETCH:
                process((ShareFetchEvent) event);
                return;

            case SHARE_ACKNOWLEDGE_SYNC:
                process((ShareAcknowledgeSyncEvent) event);
                return;

            case SHARE_ACKNOWLEDGE_ASYNC:
                process((ShareAcknowledgeAsyncEvent) event);
                return;

            case SHARE_SUBSCRIPTION_CHANGE:
                process((ShareSubscriptionChangeEvent) event);
                return;

            case SHARE_UNSUBSCRIBE:
                process((ShareUnsubscribeEvent) event);
                return;

            case SHARE_ACKNOWLEDGE_ON_CLOSE:
                process((ShareAcknowledgeOnCloseEvent) event);
                return;

            default:
                log.warn("Application event type {} was not expected", event.type());
        }
    }
An {@link EventProcessor} that is created and executes in the {@link ConsumerNetworkThread network thread}
which processes {@link ApplicationEvent application events} generated by the application thread.
clients/src/main/java/org/apache/kafka/clients/consumer/internals/events/ApplicationEventProcessor.java