1，定义一个注解，
2，定义一个切面扫拦截描这个注解即可---切面的定义可以用注解@Aspect，也可以用配置，切面可以扫描注解，包路劲
4，point.proceed();就是切点--注解所在的方法，在切面中执行（这样把目标方法放在切面通知中执行）
3，其他的地方用（写到需要监控的业务方法上(每个方法都需要写)（@ExceptionHandler不需要写在目标方法上，而是写在通知处理方法上--不需要写在监控方法上））
如果自定义注解来处理方法的异常，这回这个方法每次执行都会放在切面中的通知一起执行，然后用通知中处理异常的方式，没有异常不执行，
有异常就catch到按照通知中的逻辑处理
/** * ErrorCode: * * @author yangzhenlong * @since 2016/7/21 */ @Target({ElementType.METHOD}) @Retention(RetentionPolicy.RUNTIME) @Documented @Inherited public @interface ErrorException { int code() default 0;//参数 } /** * ErrorExceptionAspect: * * @author yangzhenlong * @since 2016/7/21 */ @Component @Aspect public class ErrorExceptionAspect { //@Before("execution(* com.sarkuya.service..*.*(..))") @Pointcut(value = "@annotation(com.mlxs.mvc.anno.ErrorException)") private void pointcut() { } @Around(value = "pointcut() && @annotation(errorExecption)") public Object around(ProceedingJoinPoint point, ErrorException errorExecption){ System.out.println("---->around"); //注解参数 System.out.println("注解参数："+ errorExecption.code()); //当前拦截的类和方法： Class clazz = point.getTarget().getClass(); Method method = ((MethodSignature) point.getSignature()).getMethod(); String codeName = clazz.getSimpleName()+"_"+method.getName(); System.out.println("query param---->"+codeName); //方法返回结果 Object result = null; Object args = Arrays.asList(point.getArgs()); try { //执行方法（可以在方法前后添加前置和后置通知） result = point.proceed(); //校验结果 result = validateResult(result); } catch (Throwable e) { //记录日志 System.out.println(codeName + "()方法异常：" + e); //打印堆栈信息 e.printStackTrace(); //设置返回信息 result = "结果：抛了异常了。。-----------------------"+e.getMessage()+"，原因："+e.getCause(); } //返回通知 return result; } /** * 方法执行后 * @param joinPoint * @param result */ @AfterReturning(value = "pointcut() && @annotation(errorExecption)", returning = "result") public Object afterReturning(JoinPoint joinPoint, ErrorException errorExecption, Object result){ System.out.println("---->afterReturning"); String methodName = joinPoint.getSignature().getName(); System.out.println("The method " + methodName + " return with " + result); if(result instanceof Boolean){ if(!((Boolean) result)){ result = "error----result is false"; } }else{ if(result == null){ result = "error----result is null"; } } return result; } /** * 方法执行后 * @param joinPoint * @param ex */ @AfterThrowing(value = "pointcut() && @annotation(errorExecption)", throwing = "ex") public void afterThrowing(JoinPoint joinPoint, ErrorException errorExecption, Exception ex){ System.out.println("eeeee--->afterThrowing"); String methodName = joinPoint.getSignature().getName(); System.out.println("The method " + methodName + "occurs exception: " + ex); } private Object validateResult(Object result){ if(result instanceof Boolean){ if(!((Boolean) result)){ System.out.println("error----result is false"); result = "error:false"; } }else{ if(result == null){ System.out.println("error----result is null"); result = "error:null"; } } return result; } } /** * _Test: * * @author yangzhenlong * @since 2016/7/21 */ @Component("test") public class _Test { public static void main(String[] args) { ApplicationContext context = new ClassPathXmlApplicationContext("classpath*:spring/applicationContext.xml"); _Test obj = (_Test) context.getBean("test"); System.out.println("==========>"+obj.test()); //System.out.println("==========>"+obj.test2()); } @ErrorException(code = 100) public Object test(){ System.out.println("---test---"); int a = 10/0; return 20; } @ErrorException(code = 22) public Object test2(){ System.out.println("---test2---"); //int a = 10/0; return false; } } ---->around 注解参数：100 query param---->_Test_test ---test--- _Test_test()方法异常：java.lang.ArithmeticException: / by zero ---->afterReturning The method test return with 结果：抛了异常了。。-----------------------/ by zero，原因：null ==========>结果：抛了异常了。。-----------------------/ by zero，原因：null java.lang.ArithmeticException: / by zero at com.mlxs.mvc.anno._Test.test(_Test.java:28) at com.mlxs.mvc.anno._Test$$FastClassBySpringCGLIB$$cc5ae48c.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:717) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:85) at com.mlxs.mvc.anno.ErrorExceptionAspect.around(ErrorExceptionAspect.java:44) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:497) at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:621) at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:610) at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:68) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:168) at org.springframework.aop.framework.adapter.AfterReturningAdviceInterceptor.invoke(AfterReturningAdviceInterceptor.java:52) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:168) at org.springframework.aop.aspectj.AspectJAfterThrowingAdvice.invoke(AspectJAfterThrowingAdvice.java:58) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:168) at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:653) at com.mlxs.mvc.anno._Test$$EnhancerBySpringCGLIB$$cbf2effd.test(<generated>) at com.mlxs.mvc.anno._Test.main(_Test.java:21) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:497) at com.intellij.rt.execution.application.AppMain.main(AppMain.java:144)