f3yourmind

Did you notice the advertising banners on my blog? I’m experimenting to see if it’s possible to earn any money from geek blogging on the narrow subject of software architecture, agility and all the other things I churn out. I’m going to let it run for a while and see what happens.

Oh, I guess I’ve got to do something about the site layout again.

It was really good to be part of a very topical subject at the JCSE Architecture Forum last night.  While these discussion are so valuable, the things that surface can only be glossed over, largely because of time constraints.  I end up feeling a very satisfied and energised but a part of me feels a bit hollow.

So here are some of the things that surfaced at the Forum, and my narrow, unworldly opinion on each (i.e. I’m just trying to fill that hollow feeling).

When we talk about architecture, we need to define what we mean by architecture?

In my talk it was a very simple view of architecture which, thinking back, I should have disclosed very early.  I am now applying from Kent Beck who talks about mutually beneficial relationships.   So I think of architecture as the mutually beneficial relationship between two or more things.  So what is a thing?  It could be  lines code in a method, methods in a class, classes in namespace, namespaces in code base, binaries in an application server, application servers in a cluster, … see where I am going?  Architecture is about creating beneficial relationships, and the 5 things I discussed are based on this view.  If you don’t know anything about the things, then you cannot create beneficial relationships.  From an agile perspective, the beneficial relationship that you create should only be beneficial based on your knowledge right now.  Tomorrow your knowledge changes, so the relationship may not be as beneficial as yesterday.  Time to change.

Building infrastructural architecture independently of functional requirements…

I am not convinced of the benefit of this approach.  In my limited experience, every business need defines the constraints or needs of the infrastructural architecture.  I find it hard to find the point of departure, yet there is a school of thought that suggests that function is orthogonal to the architecture.  Perhaps I just don’t understand this.  However from an agile perspective, I want to release early and there are many constraints on infrastructure from the business (for example, administrative processes like procurement of hardware).  I like to understand what these are early on, reach agreement on what we can release at the earliest and design accordingly.  Perhaps the first release is on lightweight infrastructure and that means we “limit” scalability.  So, I don’t design for beyond what I know is real.

Model Driven Architecture …

My view is more philosophical and abstract.  What is a model?  For me, a model is something intangible.  It is a way we understand something.  But we represent our models in many ways.  Through words in written or spoken conversation, in unstructured pictures, in structured notation like UML, even code is a representation of a model.

What do we mean by driven? I view it as a something that takes an input that produces an output.  In this case, we take an input, the model, and produce an output, an architecture.  So, I take an understanding of problem and use that to derive an architecture.  So, that’s nothing new here.  However, I don’t like to confuse driving out an architecture from a representation of the model.  That’s different.  Now we are going beyond thought processes  into mechanical processes.  Then the challenge is about how to apply the feedback to the representation of the model – and that is what will make you agile.  Too much for my small brain.

Plumbing …

Yup, we do too much hand crafted plumbing!  It’s something that we have been working on for a long, long time.  I think convention over configuration, dependency inversion, meta-programming are all attempts at addressing this problem.  Some early success that I have experienced is on taking a polyglot approach. I am not talking about mixing general purpose languages on one runtime only.  I am also including domain specific languages. I’ve had some early success where using DSL to describe functional intentions and then generating a large portion of the plumbing.  Where I’ve suffered is when I mix concepts from different domains.  There is the domain of plumbing and the domain of the business.  Whenever I’ve mixed the two, it pains later rather than sooner.  Right now, the only way I’ve had some success is with aspect orientation and meta-programming.

@StatelessSessionBean …

Chris Naidoo is right.  That thing called J2EE and subsequent versions is just horribly broken.  It’s broken encapsulation and a whole lot more.  The fact that we now must use an annotation and not implement an interface is immaterial.  Both result in the same pain – mixed concepts (see plumbing above).  Annotations should be specific to the business such as @RecalculateCostsOnRerouteOfCargo can be used as an interception point for injecting a rule on a class or method.

I would go even further and say that the POJO JavaBean specification is also broken.  Why on earth must I have a no-argument constructor and accessors and mutators.

Last thoughts …

I may have missed some of the other discussions but these are the ones that I woke up with this morning. In general, my observation is that we need to be very concrete very early if we want to be agile, even in architecture.

Metaphors may be a good way of getting to grips with a new domain.  It allows you to imagine the behavior of something that you don’t quite understand (yet) in terms of something with which you are quite familiar.  That’s were it should stop. I hate metaphors that extend beyond their purpose.  Once I have a good enough understanding, I drop the metaphor.  My reason is simple.  Metaphors force me to do a lot of energy sapping context switching.

Technical debt is one of those metaphors that have been extended so far, that it is believed by many to be something tangible.  Let’s get real here:  Technical debt does not exist.  It is just a metaphor for us to realise that our code base may cost us more money than it should, and that is a future view.  Sometimes our metaphors become euphemisms, and then it is dangerous.  When it comes to technical debt, the less I think of code problems as debt the more I am able to face the problems head on.

Ironically, I did a talk recently on dealing with technical debt.  My fundamental position is simple.  Either your code base has things that exist as a result of broken principles or it does not.  The more principles you break, the more potential problems you have in your code. It is not a problem right now, but it may be a problem in the future.  This future can be a minute away when I run my next test or a year away.  If the future is infinitely far away, then it is not a problem at all.

My first prize is to not break principles, so I don’t create potential problems.  My second prize is to deal with real problems and just leave the potential problems for the future.

(Warning: I’m drifting into my enlightenment self-reflection, so feel free to stop reading now.)

If I am part of the exploration that is looking for a solution (living in the moment and not outside it as an observer), then I should be aware of principles that I am breaking and I should change course immediately.  If I am part of the exploration that is dealing with the potential problem that is now a real problem, than I need to understand the principle that was broken and fix the problem by restoring the principle.  Restoring the principle could mean going on a search for the right solution to the original problem, not just trying to fix the problem that is a result of breaking a principle.  This problem that broke the principle may just be the wrong solution that we thought was the right solution because we ignored our principles in the first place.

Hmmm, that’s an interesting thought.  Karen Greaves asked me if a re-write can be justified and I mumbled something about technology, etc.  What tripe!  Now I think I’ve just reflected on when a rewrite is justified.  When refactoring will not fix the broken principle, then the right solution was never discovered in the first instance.  That is also what I mean when I say that clean code is necessary by not sufficient.  At factor10, we call this a radical makeover.  Radical makeovers are a viable way of getting rid of real problems, and restoring principles.

Heck!  This blog post is less about technical debt metaphors than I thought.  Oh well, the ride on this journey never stops.

By the way, a huge thank you to Steve for helping me realise that all problems come from breaking principles, in code and in life.

Marius de Beer is crazy for even trying to do this, but it is such a horribly misunderstood space that it deserves an outrageous attempt to nail it.  I’m talking about the really adventurous deep dive session that will be hosted by Marius at the Scrum Gathering in Cape Town.  If you currently think that continuous integration is a tool, then my advice is simple.  Pay the full fee for the event, sign-up for Marius’ deep dive and sacrifice the second day of the event by going back to your desk and just start doing what  you learnt.

Jimmy Nilsson asked me in an email a few days ago “How’s life?”.  I’m sure it was just a regular, friendly question, but I gave him a “life” answer.  It was not spontaneous but something that has been brooding in me for a while.   It is about things that I have been trying to do for a long time.

Here’s a few splintered thoughts from my email exchange.

• Enlightened, for me, is about happiness that comes from being content; unenlightened is just trying to be happy.
• There are many solutions for every problem, whether I am aware of them or not; and the problem has already chosen the best solution, but I have not found it yet.
• Code from my heart because I should trust myself first.
• Be part of the exploration, not just an observer.
• This moment is more important than trying to figure out how it impacts the future, because I can deal with the future in that future moment.
• Passion is constant whether I succeed or fail.
• Let the project plan me, by bending to suit the situation not and not bending the situation to suit me.
• The code I write knows everything, because every line of code has an impact on someone else or some other piece of code.

Now I’ve decided to actively explore why I write code, or why I wish to continue doing what I am doing.  I am not sure what I will uncover in this exploration, but I know that it will be very personal.  I don’t even know if it will be worth sharing, that’s why I am sharing so early.  It just felt right.

I think it will be really tough, but I take solace from my 9 year old son who told his 6 year old sister “Getting hurt is part of playing”.

PS: I don’t think Jimmy will ever ask me a “How’s life?” question again