AOP执行顺序验证

  项目引入了依赖。自动开启了aop的配置。

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

切面上配置@Order注解

  切面类AopTest1，order定义为2

@Component
@Aspect
@Order(2)
public class AopTest1 {@Pointcut("execution( * com.example.service.AopService.*(..))")public void pointCutMethod() {}@After("pointCutMethod()")public void myAfter(JoinPoint point) {System.out.println("我是AopTest1#myAfter");}@Before("pointCutMethod()")public void myBefore(JoinPoint point) {System.out.println("我是AopTest1#myBefore");}@Before("pointCutMethod()")public void myBefore2(JoinPoint point) {System.out.println("我是AopTest1#myBefore2");}@Around("pointCutMethod()")public Object around(ProceedingJoinPoint joinPoint) throws Throwable {System.out.println("我是AopTest1#around before");Object res = joinPoint.proceed();System.out.println("我是AopTest1#around after");return res;}@AfterThrowing(value = "pointCutMethod()", throwing = "e")public void afterThrowing(Exception e) {System.out.println("我是AopTest1#afterThrowing");}@AfterReturning(value = "pointCutMethod()")public void afterReturning() {System.out.println("我是AopTest1#afterReturning");}
}

  切面类AopTest2，order定义为1

@Component
@Aspect
@Order(1)
public class AopTest2 {@Pointcut("execution( * com.example.service.AopService.*(..))")public void pointCutMethod() {}@After("pointCutMethod()")public void myAfter(JoinPoint point) {System.out.println("我是AopTest2#myAfter");}@Before("pointCutMethod()")public void myBefore(JoinPoint point) {System.out.println("我是AopTest2#myBefore");}@Before("pointCutMethod()")public void myBefore2(JoinPoint point) {System.out.println("我是AopTest2#myBefore2");}@Around("pointCutMethod()")public Object around(ProceedingJoinPoint joinPoint) throws Throwable {System.out.println("我是AopTest2#around before");Object res = joinPoint.proceed();System.out.println("我是AopTest2#around after");return res;}@AfterThrowing(value = "pointCutMethod()", throwing = "e")public void afterThrowing(Exception e) {System.out.println("我是AopTest2#afterThrowing");}@AfterReturning(value = "pointCutMethod()")public void afterReturning() {System.out.println("我是AopTest2#afterReturning");}
}

  测试业务类AopService，里面会抛出异常1/0

@Service
public class AopService {public void testMethod(){System.out.println("我是AopService#testMethod");int b = 1/0;};
}

  启动类。获取AopService，调用testMethod方法。

@SpringBootApplication
public class SongDm2Application {public static void main(String[] args) {ConfigurableApplicationContext run = SpringApplication.run(SongDm2Application.class, args);AopService aopService = run.getBeanFactory().getBean(AopService.class);aopService.testMethod();}}

  执行结果如下。

  目标对象方法去掉抛出异常，执行结果如下


  总结。AOP的执行顺序如下：
  1.目标方法抛异常：Around before–>Before–>目标方法–>AfterThrowing–>After
  2.目标方法不抛异常：Around before–>Before–>目标方法–>AfterReturning–>After–>Around After
  3.同一个切面内的多个同一类型的拦截方法。按字符排序。
  4.多个切面拦截同一个方法，受@Order排序影响。目标方法执行之前，和执行之后的拦截顺序看上面的实验结果。