@Async in Spring Boot
Spring makes it super easy to execute methods asynchronously in the background using the @Async
annotation. This is helpful when you want to perform time-consuming operations (like sending emails, making external API calls, or processing large data) without blocking the main thread.
Why Use @Async
?
- Non-blocking operations: You can run heavy tasks in the background without blocking the user request.
- Performance improvements: It allows you to parallelize tasks, reducing response time.
- Clean and simple: You don’t need to deal with low-level threading or
ExecutorService
directly.
Example Scenario
Imagine you have a service that sends notification emails after a user registers. You don’t want the user to wait for the email to be sent before getting a response, so you can use @Async
to send the email in the background.
Step-by-Step Example
1. Enable @Async
in Your Application
To use @Async
, you first need to enable it in your Spring Boot application by adding @EnableAsync
in your main application class or a configuration class.
import org.springframework.boot.SpringApplication;
import…