Spring @Async Not Working

Question

An @Async method in a @Service-annotated class is not being called asynchronously - it\'s blocking the thread.

I\'ve got

Answer 1

Jiří Vypědřík's answer solved my problem. Specifically,

2. Check if your method annotated with @Async is public.

Another useful information from Spring tutorials https://spring.io/guides/gs/async-method/:

Creating a local instance of the FacebookLookupService class does NOT allow the findPage method to run asynchronously. It must be created inside a @Configuration class or picked up by @ComponentScan.

What this means is that if you had a static method Foo.bar(), calling it in that manner wouldn't execute it in async, even if it was annotated with @Async. You'll have to annotate Foo with @Component, and in the calling class get an @Autowired instance of Foo.

Ie, if you have a annotated method bar in class Foo:

@Component
class Foo { 
   @Async
   public static void bar(){ /* ... */ }

   @Async
   public void bar2(){ /* ... */ }
}

An in your caller class:

class Test {

  @Autowired Foo foo;

  public test(){
     Foo.bar(); // Not async
     foo.bar(); // Not async
     foo.bar2(); // Async
  }

}

Edit: Seems like calling it statically also doesn't execute it in async.

Hope this helps.