前面几节我们使用三种方式完成了代理，接下来，我们将看一下在spring中如何完成aop。

1、前提约束

• 完成基于注解的springmvc的demo https://www.jianshu.com/p/d1a84f07c98f

2、操作步骤

• 在src/main/resources文件夹下创建一个application-aop-anno.xml，内容如下：

<?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:context="http://www.springframework.org/schema/context"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">
<!--    用于扫描约定路径下所有的类，把包含@Component的类进行实例化 -->
    <context:component-scan base-package="net.wanho.aspect"></context:component-scan>
<!--    在上述扫描的基础上，如果有一个@Aspect的类，则会产生代理类 -->
    <aop:aspectj-autoproxy proxy-target-class="true"></aop:aspectj-autoproxy>
</beans>

• 在src/main/java文件夹下创建net.wanho.aspect.MyAspect.java，内容如下：

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.*;
import org.springframework.stereotype.Component;

import java.util.Arrays;

@Aspect
@Component
public class MyAspect {

    @Pointcut("execution(* net.wanho.aspect.StudentService.*())")
    public void pointCut(){}

    @After("pointCut()")
    public void testPointcut()
    {
        System.out.println("testPointcut");
    }

    @Before("execution(* net.wanho.aspect.StudentService.*(..))")
    public void security(JoinPoint joinPoint)
    {
        System.out.println(joinPoint.getKind()+"."+joinPoint.getSignature().getName()+":("+Arrays.toString(joinPoint.getArgs())+")");
        System.out.println("权限");
    }

    @Around("execution(* net.wanho.aspect.StudentService.*(int)))")
    public Object around(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
        System.out.println("around in");

        Object object = proceedingJoinPoint.proceed();

        System.out.println("around out");
        return object;
    }

    @AfterThrowing("execution(* net.wanho.aspect.StudentService.*(int)))")
    public void afterThrowing()
    {
        System.out.println("exception");
    }

    @AfterReturning("execution(* net.wanho.aspect.StudentService.*(int)))")
    public void afterReturning()
    {
        System.out.println("return");
    }
}

• 在src/main/java文件夹下创建net.wanho.aspect.StudentService.java

public interface StudentService {
    void query();
}

• 在src/main/java文件夹下创建net.wanho.aspect.StudentServiceImpl.java

import net.wanho.class134.entity.Student;
import org.springframework.stereotype.Component;

import java.util.HashMap;
import java.util.Map;

@Component(value = "studentService")
public class StudentServiceImpl implements StudentService {
    @Override
    public void query() {
        System.out.println("查询");
    }
}

• 在src/main/java文件夹下创建net.wanho.aspect.Test.java

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Test {

    public static void main(String[] args) throws Exception {
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("application-aop-anno.xml");
        StudentService studentService = applicationContext.getBean("studentService", StudentService.class);

        studentService.query();
    }
}

以上就是采用注解方式完成aop的过程。

04 注解方式完成aop

原文：https://www.cnblogs.com/alichengxuyuan/p/12554684.html