我在ShoppingCart.java中的public int quantity()方法的切入点不起作用。我试图创建一个切入点来捕获public int quantity()方法的返回值，但是@AfterReturning切入点的相关建议似乎没有被调用，即使在主方法调用了quantity方法之后（参见文件AuthenticationAspect.java，它试图定义一个afterReturning切入点）。
文件ShoppingCart.java

package org.example;

import org.springframework.stereotype.Component;

@Component
public class ShoppingCart {

    public int quantity()
    {
        System.out.println("\n Quantity method called");
        return 2;
    }
}

AuthenticationAspect.java

package org.example;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;

@Aspect
@Component
public class AuthenticationAspect {

    @Pointcut("execution(* org.example.ShoppingCart.quantity())")
    public void afterReturningPointCut()
    {
    }

    @AfterReturning(pointcut = "afterReturningPointCut()", returning = "retVal")
    public void afterReturning(String retVal)
    {
        System.out.println("The quantity used is " + retVal);
    }
}

Main.java

package org.example;

import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

public class Main {
    public static void main(String[] args) {
        ApplicationContext context = new AnnotationConfigApplicationContext(BeanConfig.class);

        ShoppingCart cart = context.getBean(ShoppingCart.class);

        cart.quantity();
    }
}