== Why is this an issue?

A method annotated with Spring's `@Async` or `@Transactional` annotations will not work as expected
if invoked directly from within its class.

This is because Spring generates a proxy class with wrapper code to manage the method's asynchronicity (`@Async`)
or to handle the transaction (`@Transactional`).
However, when called using `this`, the proxy instance is bypassed, and the method is invoked directly
without the required wrapper code.

== How to fix it

Replace calls to `@Async` or `@Transactional` methods via `this`
with calls on an instance that was injected by Spring (`@Autowired`, `@Resource` or `@Inject`).
The injected instance is a proxy on which the methods can be invoked safely.

=== Code examples

==== Noncompliant code example

[source,java,diff-id=1,diff-type=noncompliant]
----
@Service
public class AsyncNotificationProcessor implements NotificationProcessor {

  @Override
  public void process(Notification notification) {
    processAsync(notification); // Noncompliant, call bypasses proxy
  }

  @Async
  public processAsync(Notification notification) {
    // ...
  }
}
----

==== Compliant solution

[source,java,diff-id=1,diff-type=compliant]
----
@Service
public class AsyncNotificationProcessor implements NotificationProcessor {

  @Resource
  private AsyncNotificationProcessor

  @Override
  public void process(Notification notification) {
    asyncNotificationProcessor.processAsync(notification); // Compliant, call via injected proxy
  }

  @Async
  public processAsync(Notification notification) {
    // ...
  }
}
----

== Resources

=== Documentation

- https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/scheduling/annotation/Async.html[Spring Framework API - Annotation Interface Async]
- https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/transaction/annotation/Transactional.html[Spring Framework API - Annotation Interface Transactional]

=== Articles & blog posts

- https://www.baeldung.com/spring-async[Baeldung - How To Do @Async in Spring]
- https://stackoverflow.com/questions/22561775/spring-async-ignored[Stack Overflow - Spring @Async ignored]
- https://stackoverflow.com/questions/4396284/does-spring-transactional-attribute-work-on-a-private-method[Stack Overflow - Does Spring @Transactional attribute work on a private method?]