引自：http://www.mkyong.com/spring3/spring-aop-aspectj-annotation-example/
AspectJ方法
- @Before – Run before the method execution
- @After – Run after the method returned a result
- @AfterReturning – Run after the method returned a result, intercept the returned result as well.
- @AfterThrowing – Run after the method throws an exception
- @Around – Run around the method execution, combine all three advices above.
