Lifecycle Events

Register handlers for Javalin server lifecycle events directly in your endpoint classes using @LifecycleEventHandler.

Basic Usage

@Endpoints("/api")
class AppEndpoints {

    @LifecycleEventHandler(lifecycleEvent = JavalinLifecycleEvent.SERVER_STARTED)
    void onServerStarted() {
        System.out.println("Server is ready!");
    }

    @LifecycleEventHandler(lifecycleEvent = JavalinLifecycleEvent.SERVER_STOPPING)
    void onServerStopping() {
        System.out.println("Server is shutting down...");
    }

}

Available Events

Event	Description
SERVER_STARTING	Server is starting up
SERVER_STARTED	Server has started successfully
SERVER_START_FAILED	Server failed to start
SERVER_STOPPING	Server is shutting down
SERVER_STOPPED	Server has stopped
SERVER_STOP_FAILED	Server failed to stop cleanly

Use Cases

Initialize Resources on Startup

@LifecycleEventHandler(lifecycleEvent = JavalinLifecycleEvent.SERVER_STARTED)
void initializeCache() {
    cacheService.warmUp();
}

Cleanup on Shutdown

@LifecycleEventHandler(lifecycleEvent = JavalinLifecycleEvent.SERVER_STOPPING)
void cleanup() {
    connectionPool.close();
    scheduledTasks.shutdown();
}

Error Reporting

@LifecycleEventHandler(lifecycleEvent = JavalinLifecycleEvent.SERVER_START_FAILED)
void reportStartupFailure() {
    alertService.notify("Server failed to start!");
}