Top 10 questions related to Async processing in Spring

How do you enable asynchronous processing in Spring?
Use @EnableAsync on a configuration class to enable async support.

How do you define an asynchronous method in Spring?
Annotate the method with @Async and ensure it returns void, Future, CompletableFuture, or ListenableFuture.

How do you configure a thread pool for async tasks in Spring?
Define a ThreadPoolTaskExecutor bean and customize its properties like pool size.

What happens if an async method throws an exception?
Exceptions are caught by the async executor; use AsyncUncaughtExceptionHandler to handle them.

How do you schedule a recurring task in Spring?
Use @Scheduled with attributes like fixedRate, fixedDelay, or cron for scheduling.

What is the difference between @Async and @Scheduled?
@Async runs methods asynchronously on demand, while @Scheduled runs tasks on a fixed schedule.

How do you ensure a scheduled task runs only once across a cluster?
Use a distributed lock or a task scheduler like Quartz with database persistence.

Can you call an @Async method from the same class?
No, it requires a proxy; call it from another bean or use ApplicationContext to get the bean.

How do you monitor the status of async tasks in Spring?
Use CompletableFuture or ListenableFuture to track task completion or add custom logging.

What is the default executor for @Async in Spring?
Spring uses a SimpleAsyncTaskExecutor, creating a new thread per task unless customized.