Ubuntu 7.04

Ubuntu Linux 7.04 came out, I did upgrade and everything goes fine.
Many guys in Java community get excited that JDK 1.6 is already in it's repository. My OpenOffice got updated to 2.2 as well, and that's great.

I've also tried it in VMWare player and, of course, there's no correct driver for 7.04 at the moment. The problem I have is just about the mouse. But it's not a big deal, I tweaked XOrg.conf and set the driver back to the original one ("mouse" instead of "vmmouse").

My new Ubuntu experience has just started !

AOP for Groovy is here !! Code moved to be Grails-AOP

AOP for Groovy is here !

I've just refactored and uploaded my AOP subsystem into the Grails-Plugins repo. Anyway, it cannot say that this AOP implementation is Grails-Plugins. It's likely to be a drop-in module because it contains ObjectMetaClass that will hook into system-wide metaclass instantiation process.

This is an AspectJ-like, the pointcut-advice model implementation of AOP for Groovy. Both 2 important properties of AOP, Quantification and Obliviousness, has been implemented by design.

Browse the repo: http://svn.codehaus.org/grails-plugins/grails-aop/

The ways to express pointcuts, the choice is yours

From the non-AOP programmers' perspective, the pointcut mini-language in AspectJ seems to be a bit difficult to learn. Before they can start writing some aspects, they need to know background concepts about join points, the way how to quantify them with a combination of pointcut designators, and the way how to express advice codes.

I cannot argue this because making pointcut languages simple yet powerful is quite an active research in the AOP area.

Some workaround to solve this problem could be having different kind of way to express pointcuts in one framework. So this means we're going to have several mini-languages inside the host language for describing aspects. They are what I'm going to implement for my AOP subsystem for Groovy.

For example, call() PCD is a quite common one you often use, so having:

Test.around['test*'] = {} instead of around(): call(Test.test*(..)) { }

can reduce the learning curve.

But when, the power of the basic pointcut language is not enough, you can use the full version of pointcut language, like this:

static aspect = {
def p = pointcut{
pcall('public *':'set*') & pcall( ... ) &
within(MyClass:'some*')
}
around(p) { context ->
proceed(context.args)
}
}

The choice of expressing pointcuts is just yours.

Aspect Groovy: Per class and Per instance

From last post, I'm going to the next step by re-implementing my AOPSupportMetaClass again in Java to have some precise controls. Now the AOP metaclass got updated and support weaving both per class and per instance. However, the pointcut expression style is still based on John McClean's implementation.

This is for per instance weaving

def t = new TestObject()
t.around['save'] = { inv ->
inv.args[0] = inv.args[0] + '.'
inv.proceed(inv.args)
}
t.save('test')

And you can guess, this is per class weaving

TestObject.around['save'] = { inv ->
inv.args[0] = inv.args[0] + '.'
inv.proceed(inv.args)
}
def t = new TestObject()
t.save('test')

Last test code can be obtained from here.