一文拆解Spring AOP 核心概念与通知类型

import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.*;
import org.springframework.stereotype.Component;
@Slf4j
@Aspect
@Component
public class AspectDemo {
    // 公共切点：抽取表达式，所有通知复用
    @Pointcut("execution(* com.example.demo.controller.*.*(..))")
    private void pt(){}
    @Before("pt()")
    public void doBefore(JoinPoint joinPoint){
        log.info("@Before 前置通知执行");
    }
    @AfterReturning("pt()")
    public void doAfterReturning(JoinPoint joinPoint){
        log.info("@AfterReturning 返回通知执行");
    }
    @AfterThrowing("pt()")
    public void doAfterThrowing(JoinPoint joinPoint){
        log.info("@AfterThrowing 异常通知执行");
    }
    @After("pt()")
    public void doAfter(JoinPoint joinPoint){
        log.info("@After 后置通知执行");
    }
    @Around("pt()")
    public Object doAround(ProceedingJoinPoint pjp) throws Throwable {
        log.info("@Around 环绕【前置】逻辑");
        Object result = null;
        try {
            // 执行目标方法
            result = pjp.proceed();
        } catch (Throwable throwable) {
            throw throwable;
        }
        log.info("@Around 环绕【后置】逻辑");
        return result;
    }
}

import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@Slf4j
@RestController
@RequestMapping("/test")
public class TestController {
    // 正常执行接口
    @GetMapping("/t1")
    public String t1(){
        log.info("===== 目标方法 t1 正在执行 =====");
        return "success";
    }
    // 会抛出异常的接口
    @GetMapping("/t2")
    public String t2(){
        log.info("===== 目标方法 t2 正在执行 =====");
        int a = 10 / 0;
        return "success";
    }
}

@Pointcut("execution(* com.example.demo.controller.*.*(..))")
private void pt(){} // 定义切点
@Before("pt()") // 引用切点
public void doBefore() { ... }