SpringAOP学习之5种通知

一、Spring的AOP分为以下5种类型通知

①前置通知（Before）：在连接点执行前执行该通知

②正常返回通知（AfterReturning）：在连接点正常执行完后执行该通知，若目标方法执行异常则不会执行该通知

③异常返回通知（AfterThrowing）：在连接点执行抛出异常时执行该通知

④后置通知（after/finally）：在连接点执行完成后（不管成功、失败、异常）都会执行该通知

⑤环绕通知（Around）：围绕在连接点前后

二、执行顺序

1、正常执行

①环绕通知：@Around

②前置通知：@Before

③连接点方法执行

④环绕通知：@Around

⑤后置通知：@After

⑥正常返回通知：@AfterReturning

　　其他结论说出来也没意思，还是自己通过简单demo测试一下就出来了

三、测试

1、自定义注解

2、切面

@Aspect

@Component

@Slf4j

public class LogAspect {

    //切点范围

    @Pointcut("@annotation(com.test.annotation.OperateLog)")

    public void operateMethod(){}

    //前置通知

    @Before("operateMethod()")

    public void before(){

        log.info("前置通知：Before");

    }

    //正常返回通知

    @AfterReturning("operateMethod()")

    public void afterReturning(){

        log.info("后置通知：AfterReturning");

    }

    //后置通知

    @After("operateMethod()")

    public void after(){

        log.info("后置通知：After");

    }

    //异常返回通知

    @AfterThrowing("operateMethod()")

    public void afterThrowing(){

        log.info("异常返回通知：AfterThrowing");

    }

    //环绕通知

    @Around("operateMethod()")

    public Object methodAround(ProceedingJoinPoint joinPoint) throws Throwable{

        log.info("环绕通知：around------前");

        Object result=null;

        OperateLog annotation = getAnnotation(joinPoint);

        try {

            result=joinPoint.proceed();

        } catch (Throwable throwable) {

            log.info("环绕通知：around------异常");

        }

        try {

            String system = annotation.system();

            int flag = annotation.flag();

            String operatorName = annotation.operatorName();

            log.info("切面校验信息，系统：【{}】,标识:【{}】,操作员名称：【{}】", system,flag,operatorName);

            //日志入库业务

        } catch (Exception e) {

            log.info("切面异常",e);

        }

        log.info("环绕通知：around------后");

        return result;

    }

    private OperateLog getAnnotation(JoinPoint joinPoint){

        MethodSignature signature = (MethodSignature)joinPoint.getSignature();

        Method method = signature.getMethod();

        return method.getAnnotation(OperateLog.class);

    }

}

切面代码

3、定义service接口并实现

service接口

实现类

4、测试controller

@RestController

@Slf4j

public class LogController {

    @Autowired

    private IHelloService helloService;

    @RequestMapping("/test")

    @OperateLog(system = "系统1",flag = 1,operatorName = "操作员1")

    public void test() throws Exception {

        OperateLog test = (OperateLog)AnnotationUtil.getAnnotation(LogController.class, OperateLog.class, "test", 1);

        log.info("更改前的注解属性:【{}】,【{}】,【{}】",test.flag(),test.operatorName(),test.system() );

        //更改注解OperateLog的system属性值为“系统2”

        AnnotationUtil.ModifyAnnotation(LogController.class, OperateLog.class, "test", "system", "系统2");

        //更改flag的属性值为2

        AnnotationUtil.ModifyAnnotation(LogController.class, OperateLog.class, "test", "flag", 2);

        //更改注解的operatorName属性值为：张三

        AnnotationUtil.ModifyAnnotation(LogController.class, OperateLog.class, "test", "operatorName", "张三");

        log.info("更改后的注解属性:【{}】,【{}】,【{}】",test.flag(),test.operatorName(),test.system() );

    }

    @RequestMapping("/test1")

    @OperateLog(system = "系统1",flag = 1,operatorName = "操作员1")

    public void test1() throws Exception {

        helloService.IsayHello();

    }

    @RequestMapping("/test2")

    @OperateLog(system = "系统1",flag = 1,operatorName = "操作员1")

    public void test2() throws Exception {

        helloService.say("我是controller");

    }

    @RequestMapping("/test3")

    @OperateLog(system = "系统1",flag = 1,operatorName = "操作员1")

    public void test3() throws Exception {

        helloService.error(true);

    }

    @RequestMapping("/test4")

    @OperateLog(system = "系统1",flag = 1,operatorName = "操作员1")

    public void test4() throws Exception {

        helloService.error(false);

    }

}

controller

5、测试

三、总结

1、Aop可以理解为一个同心圆，要执行的目标方法（底层还是jdk或cglib动态代理）为圆心，最外层的order最小，环绕、前置通知先执行，后置、正常返回通知后执行

2、多个aop执行的执行顺序可以使用@Order注解来实现

本项目地址：https://github.com/Simple-Coder/aop-demo

巴特西