如何在Spring AOP中定义通知？

@Aspect
@Component
public class TimeRecordingAspect {

    @Pointcut("execution(* com.tianmaying.aopdemo..*.bookFlight(..))")
    private void timeRecordingPointCut() {
    }

    @Around("timeRecordingPointCut()") //1
    public Object recordTime(ProceedingJoinPoint pjp) throws Throwable {  //2

        long start = System.currentTimeMillis();
        Object retVal = pjp.proceed(); // 3

        long duration = System.currentTimeMillis() - start;
        System.out.println(String.format(
                "time for booking flight is %d seconds", duration));

        return retVal;
    }
}