logging - How to automatically log the entry/exit of methods in Java?

Question

Right now I am using java.util.logging to log the entry and exit points of each method in my Java project. This is very useful to me when debugging.

I have this piece of code at the beginning of each method and a similar one at the end:

if (logger.isLoggable(Level.FINER)) {
    logger.entering(this.getClass().getName(), "methodName");
}

Where "methodName" is the the name of the method (hardcoded).

So I was wondering if there is a way to do this automatically without having to include this code in every method.

Answer 1

I suggest the use of Aspect Oriented Programming.

For example, using the AspectJ compiler (which can be integrated to Eclipse, Emacs and others IDEs), you can create a piece of code like this one:

aspect AspectExample {
    before() : execution(* Point.*(..))
    {
         logger.entering(thisJoinPointStaticPart.getSignature().getName(), thisJoinPointStaticPart.getSignature().getDeclaringType()   );

    }

    after() : execution(* Point.*(..))
    {
         logger.exiting(thisJoinPointStaticPart.getSignature().getName() , thisJoinPointStaticPart.getSignature().getDeclaringType()  );

    }
}

This aspect adds a logging code after and before the execution of all methods in the class "Point".