Question

我是Spring AOP的新手，我想知道是否可以将@Before的值返回给方法并在其中使用此变量，例如：

@Before("@annotation(CheckUserReservationPermission) && args(username,idReservation)")
public Reservation userCreationAdvice(ProceedingJoinPoint pjp, String username, Integer idReservation) throws Throwable {
    Reservation reservation = reservationServices.findById(idReservation);
    if (!reservation.getUser().getUsername().equals(username))
        throw new PermissionException("You can't delete the reservation with id: " + idReservation);
    return reservation;
}

和我的方法：

@Override
@CheckUserReservationPermission
public void deleteReservationById(String username, Integer idReservation) throws QueryException {
    synchronized(ReservationsSchedulerServicesImpl.class){
        databaseReservationServices.deleteReservationById(username, reservation);  
    }
}

有没有办法做到这一点？否则我必须重复查询。感谢

更新：使用@Around我可能有此代码，但如何将变量检索到deleteReservationById方法？

@Around("@annotation(CheckUserReservationPermission) && args(username,idReservation)")
public Object userCreationAdvice(ProceedingJoinPoint pjp, String username, Integer idReservation) throws Throwable {
    Reservation reservation = reservationServices.findById(idReservation);
    if (!reservation.getUser().getUsername().equals(username))
        throw new PermissionException("You can't delete the reservation with id: " + idReservation);
    return pjp.proceed(new Object[] {reservation});
}

Answer 1

编辑2：

建议

@Around("@annotation(CheckUserReservationPermission) && args(username,idReservation)")
public Object userCreationAdvice(ProceedingJoinPoint pjp, DeleteByIdRequest req) throws Throwable {
    Reservation reservation = reservationServices.findById(idReservation);
    if (!reservation.getUser().getUsername().equals(username)) {
        throw new PermissionException("You can't delete the reservation with id: " + idReservation);}

     req.setReservation(reservation);  
    return pjp.proceed(new Object[] {req});

}

2。新请求POJO

 class DeleteByIdRequest {
      Reservation reservation;
      String username;
      Integer idReservation;
    }

3.目标方法

@Override
@CheckUserReservationPermission
public void deleteReservationById(DeleteByIdRequest request) throws QueryException {
    synchronized(ReservationsSchedulerServicesImpl.class){
        databaseReservationServices.deleteReservationById(username, reservation);  
    }
}

查看此建议的界面，

检查他们返回的内容。

1.ThrowsAdvice

public void afterThrowing(IllegalArgumentException e) throws Throwable {
}

2.AfterReturningAdvice

public void afterReturning(Object returnValue, Method method,
        Object[] args, Object target) throws Throwable {
}

3.MethodBeforeAdvice

public void before(Method method, Object[] args, Object target)
        throws Throwable {

}

4.MethodInterceptor（围绕建议）

public Object invoke(MethodInvocation methodInvocation) throws Throwable {

}

如果您在第4点注意仅周围建议返回对象。

你必须定义joinPoint.proceed（）来控制拦截器何时将控件返回到原始方法。

检查简单示例here

修改我认为这可以在proceeding with arguments的帮助下实现
基本上你可以用新参数调用proceed（）。

Spring AOP @Before建议返回值

1 个答案: