SpringAOP常用功能实现

1. 导入依赖

<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-aop</artifactId>
</dependency>

2. 核心通知

package com.example.aspect;import lombok.SneakyThrows;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.After;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.AfterThrowing;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;@Aspect
@Order(1)
@Component
public class RequestAspect {@Pointcut("execution(* com.example.controller..*(..))")public void pc() {}/*** around通知必须有返回值*/@SneakyThrows@Around("com.example.aspect.RequestAspect.pc()")public Object around(ProceedingJoinPoint joinPoint) {System.out.println("around start");Object result = joinPoint.proceed();System.out.println("around end");return result;}@Before("pc()")public void before() {System.out.println("before");}@After("pc()")public void after() {System.out.println("after");}@AfterReturning("pc()")public void afterReturning() {System.out.println("afterReturning");}@AfterThrowing("pc()")public void afterThrowing() {System.out.println("afterThrowing");}
}

around start
before
@RequestMapping
afterReturning
after
around end

3. 执行顺序

@Around joinPoint.proceed()

@Before @RequestMapping @AfterReturning/@AfterThrowing @After

@Around

4. 切点表达式

4.1 execution方法签名匹配

返回类型和异常可以省略。

execution(<访问修饰符> <返回类型> <包名.类名.⽅法(⽅法参数)> <异常>)

@Pointcut("execution(* com.example.controller..*(..))")

4.2 @annotation注解匹配

@annotation(注解路径)

@Pointcut("@annotation(org.springframework.web.bind.annotation.RequestMapping)")

4.3 @Pointcut切点表达式

@Pointcut可以定义公共切点表达式，也可以在其他切面类中使用。

@Around("com.example.aspect.RequestAspect.pc()")