Event Listener class.

EntityCreatedEventListener.java

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationListener;
import org.springframework.stereotype.Component;

@Component
public class EntityCreatedEventListener implements ApplicationListener<EntityCreatedEvent> {

  @Autowired
  private EmailService emailService;

  @Override
  public void onApplicationEvent(EntityCreatedEvent event) {
    if (event.getEntity() != null) {
      if (event.getEntity() instanceof Project) {
        emailService.sendProjectCreatedMail(project.getOwnerEmail());
      }
    }
  }
}