public class AsyncApp {
  public static void main(String[] args) {
    ConfigurableApplicationContext ctx = new AnnotationConfigApplicationContext(Config.class);
    HelloService hello = ctx.getBean("helloService", HelloService.class);
    hello.hello();
  }

  @Configuration
  @EnableAsync(mode = AdviceMode.ASPECTJ) // 使用 aspectj 增强
  static class Config {
    @Bean
    public HelloService helloService() {
      return new HelloService();
    }

    @Bean
    public ConcurrentTaskExecutor executor() {
      return new ConcurrentTaskExecutor();
    }
  }
}

public class HelloService {
  @Async
  public void hello() {
    System.out.println("hello");
  }
}

public class AspectjApp {
  public static void main(String[] args) {
    ConfigurableApplicationContext ctx = new AnnotationConfigApplicationContext(Config.class);
    HelloService hello = ctx.getBean("helloService", HelloService.class);
    hello.hello();
  }

  @Configuration
  @EnableAspectJAutoProxy
  @EnableLoadTimeWeaving // 打开 load-time weaving 功能
  static class Config {
    @Bean
    public HelloService helloService() {
      return new HelloService();
    }

    @Bean
    public Interceptor myInterceptor() {
      return new Interceptor();
    }
  }
}

public class HelloService {
  public void hello() {
    System.out.println("hello");
  }
}

@Aspect
public class Interceptor {
  @Pointcut("execution(* HelloService.hello(..))")
  public void PointCut() {}

  @Before("PointCut()")
  public void before() {
    System.out.println("before");
  }
}