Writing the Aspect class

Consider our logging class. Which requires to log depending on what method we entered, left etc. whatever user requires. So we have to follow following steps:

1. Write a class which will contain the common logging code. This is called Aspect.
2. Either by xml or annotations we will have to configure a pointcut, to specify when(before, after, before return) and where(for all beans or only for a few bean or for a particular method pattern) will this aspect apply.

import org.aspectj.lang.JoinPoint;

//This is an Aspect class
public class LoggingAspect {

//This is an advice.
//Pointcut means where will this advice be applied.
public void log(JoinPoint joinPoint) {
System.out.println("common logging code executed for : "+joinPoint);
}

}
Methods of the Aspect class can be logically be called as advices.
We can use annotations or xml to configure the pointcut.
XML configuration for pointcuts
Annotation configuration for pointcuts