How to Implement Asynchronous Calls in Spring Boot with @Async

This article is about how asynchronous behaviour can be achieved in spring boot.

• Synchronous Programming: In synchronous programming, tasks are performed one at a time and only when one is completed the next is unblocked.
• Asynchronous Programming: In asynchronous programming, multiple tasks can be executed simultaneously. You can move to another task before the previous one finishes.

In spring boot, we can achieve asynchronous behaviour using @Async annotation. But just @Async annotation will not work. For that, you need to understand how @Async internally works.

Spring comes with @EnableAsync annotation and can be applied to a @Configuration class for asynchronous behavior. The @EnableAsync annotation will look for methods marked with @Async annotation and run them in background thread pools.

The @Async annotated methods are executed in a separate thread and return CompletableFuture to hold the result of an asynchronous computation.

To enable async configuration in spring, follow these steps:

• Create a thread pool to run…