利用注解在Spring框架中实现面向切面编程（AOP）

1、定义注解

&＃64;Retention(RetentionPolicy.RUNTIME)
&＃64;Target({ElementType.METHOD})
public &＃64;interface RetryMethod {int retryCnt() default 1;int retryUnit() default 1000;}


2、切面

&＃64;Aspect
&＃64;Component
&＃64;Log4j
public class AopIntercepter {private Logger logger &＃61; LoggerFactory.getLogger(this.getClass());&＃64;Around("&＃64;annotation(com.youzan.test.util.aop.RetryMethod)")public void around(ProceedingJoinPoint joinPoint) throws Throwable{Method currentMethod &＃61; this.getCurrentMethod(joinPoint);String mName &＃61; currentMethod.getName();Object result &＃61; null;RetryMethod retry &＃61; currentMethod.getAnnotation(RetryMethod.class);boolean flag &＃61; false;int retryCount &＃61; retry.retryCnt();while (!flag&&retryCount>0){flag &＃61; true;try {logger.info("方法名&＃xff1a; "&＃43;mName&＃43;"开始执行");System.out.println("方法名&＃xff1a; "&＃43;mName&＃43;"开始执行");result &＃61; joinPoint.proceed();}catch (Throwable e){flag &＃61; false;retryCount -- ;Thread.sleep(retry.retryUnit());logger.info("方法名&＃xff1a; "&＃43;mName&＃43;"重试第"&＃43;(retry.retryCnt()-retryCount)&＃43;"次");if(retryCount &＃61;&＃61; 0){throw e;}}}}private Method getCurrentMethod(ProceedingJoinPoint joinPoint) {MethodSignature msig &＃61; (MethodSignature)joinPoint.getSignature();try {return joinPoint.getTarget().getClass().getMethod(msig.getName(), msig.getParameterTypes());} catch (NoSuchMethodException var4) {throw new RuntimeException("这就不该有问题");}}}


3、使用

&＃64;Component
public class AopTestCase {private int i &＃61; 0;&＃64;RetryMethod(retryCnt&＃61;2,retryUnit &＃61; 1050)public void test(){Long sum &＃61; 5l;System.out.println("hello,i&＃61;"&＃43;i);i&＃43;&＃43;;Assert.assertTrue(sum<0,"大于0");System.out.println("after test");}public void testMethod(){System.out.println("test test");}
}