The final structure of each class is as follows:

1,Factory

package com.test.aspectj.expression;

/**
 * Factory interface
 */
public interface Factory {

    // Make products
    void make();

    // transport
    void delivery(String address);
}

2,PhoneFactory

package com.test.aspectj.expression;

import com.test.aspectj.expression.annotation.Log;
import org.springframework.stereotype.Component;

/**
 * Mobile phone factory
 */
@Component
public class PhoneFactory implements Factory {

    // Note @ Log annotation for the method of making products
    @Override
    @Log
    public void make() {
        System.out.println("From target class PhoneFactory Message: making mobile phones");
    }

    // How to transport mobile phones
    @Override
    public void delivery(String address) {
        System.out.println("From target class PhoneFactory Message for: Transport mobile phone to " + address);
    }

 }

3,FoodFactory

package com.test.aspectj.expression;

import com.test.aspectj.expression.args.FreshFoodFactory;
import com.test.aspectj.expression.args.FrozenFoodFactory;
import org.springframework.stereotype.Component;

/**
 * Food factory
 */
@Component
public class FoodFactory implements Factory {
    // How to make products
    @Override
    public void make() {
        System.out.println("From target class FoodFactory News of: food production");
    }

    // transport
    @Override
    public void delivery(String address) {
        System.out.println("From target class FoodFactory Sales of food to " + address);
    }

}

4. Custom annotation Log

package com.test.aspectj.expression.annotation;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Custom log annotation
 */
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface Log {
    boolean value() default true;
}

5. Annotation aspect, @annotation Code example

package com.test.aspectj.expression.annotation;

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

/**
 * Use @ annotation() to weave enhancements for all methods annotated with @ Log
 */
@Aspect
public class AnnotationAspect {
    @AfterReturning("@annotation(com.test.aspectj.expression.annotation.Log)")
    public void log() {
        System.out.println("Message from aspect: print log");
    }
}

6,xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans 
       http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/aop 
       http://www.springframework.org/schema/aop/spring-aop.xsd 
       http://www.springframework.org/schema/context 
       http://www.springframework.org/schema/context/spring-context.xsd">
    
    <context:component-scan base-package="com.test.aspectj.expression"/>
    <bean id="annotationAspect" class="com.test.aspectj.expression.annotation.AnnotationAspect"/>
    <aop:aspectj-autoproxy/>
</beans>

7. Test code

package com.test.aspectj.expression.annotation;

import com.test.aspectj.expression.Factory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

/**
 * Test execution aspect aspect
 */
public class AspectJExpressionDemo {
    public static void main(String[] args) {
        System.out.println("=============== test @annotation ===============");
        ApplicationContext context = new ClassPathXmlApplicationContext("classpath:spring-chapter3-aspectjannotationexpression.xml");
        Factory foodFactory = (Factory) context.getBean("foodFactory");
        // There is no @ Log annotation on the foodfactory ා make method, so it will not be enhanced
        System.out.println("FoodFactory#There is no @ Log annotation on the make method, so it will not be enhanced ');
        foodFactory.make();
        System.out.println("-----Dividing line-----");
        Factory phoneFactory = (Factory) context.getBean("phoneFactory");
        // The @ Log annotation on the phonefactory ා make method will be enhanced
        System.out.println("PhoneFactory#The @ Log annotation on the make method will be enhanced ');
        phoneFactory.make();
    }
}

8. Operation results

===============Test @ annotation===============
There is no @ Log annotation on the foodfactory ා make method, so it will not be enhanced
Message from the target class FoodFactory: produce food
-----Dividing line-----
The @ Log annotation on the phonefactory ා make method will be enhanced
Message from target class PhoneFactory: production phone
Message from aspect: print log

11. Conclusion

• There is no @ Log annotation on the foodfactory ා make method, so it will not be enhanced
• The @ Log annotation on the phonefactory ා make method will be enhanced