Technology Grudges and the Cult of Building Your Own Software
It has come to pass that in my travels, I have been introduced to or worked with people with certain grudges in the technology realm. Myself included, it is pretty simple to run into a problem in an experience that sours you on a particular tool. Hell, my father-in-law held a pretty decent grudge against Honda automobiles until the early 90's. The reason's for his slight towards the maker of the Accord was a bit different from the people I come across who hold technologies in low regard - the people who roll their eyes at Java, the religious fanatics who loathe all things Microsoft, the experienced programmers who will never touch Perl. We tend to be shaped more by our poor experiences than our positive ones. The technologist "grudge" is the burden some people carry with them for a lifetime after a poor experience, and while it's understandable and to an extend prudent to adopt a once bitten, twice shy perspective, it is more valuable to take that experience and either improve the subject technology (particularly in the instances of community software) or evaluate alternatives that exist.
But some of the weary techies I've worked with (particularly middle-management types, for some reason) go off the deep end. I like to say that when you encounter a technical challenge - there's likely someone else who has also needed to solve a similar problem. In the instances where that isn't the case - you're in a pretty good position to gain something from solving it yourself. But truth be told, there are very few large problems out there that people aren't solving. And yet IT organizations continue to re-invent the wheel - even when economics and time tell them that they should look for an off-the-shelf solution. This only leaves one real driver for making the build decision when the buy decision is so apparent: politics. And often it's the politics of the grudge.
I firmly believe that every shop I've walked into that has rolled their own MVC framework, or RIA framework, or rules framework contains an individual who truly believes that the cost of supporting, maintaining, and continuously developing that software is still less than the cost of taking a turnkey solution - either one that is commercial or open source. I recently had a manager tell me that there was an increasing drive through the IT management structure that the enterprise should own the source and rights to all of the systems that it supports. This was a crazy notion - are their boundaries to this doctrine? Will we be writing our own application servers? RDBMS? Messaging systems? Where does this cult draw the line? And with a little more digging, and without much surprise - I found that this manager had spearheaded a campaign to adopt a particular Javascript framework for client development that ultimately failed and cost the company several millions of dollars. His dogma seemed crazy, and it was. But it was completely motivated out of fear that technology selection, no matter where the accountability lay - was an avoidable cost of enterprise IT, even if it meant adopting the more extensive cost of building all solutions from the ground up whenever the need arose.
I guess the moral of the story is really that as an IT manager, it's important to recognize the power of the crowd (the community if you will) and the value it can add at virtually no cost to your organization. That it's important to understand why a 3rd party tool has been selected. That it's general limitations are known early on. That your organization is prepared to adopt the tool as if it were it's very own. This means hiring experts who have used those technologies. And above and beyond anything else, that when you fail - the goal must be to marginalize the cost of that failure. You can hedge your bets, you can reduce risk. But when the dust settles and a selected technology has failed the organization - be sure to take a good hard look in the mirror and be open about where the selection process has failed.
Sometimes it is the captain, and not the ship.
RPC Objects in GWT Now MUST be Serializable
Okay, so maybe it's always been this way and I've just not been paying attention - but it appears that GWT 2.0 now requires one to make RPC objects that will go across the wire explicitly implement java.io.Serializable.
A bland RPC implementation that was based on past work I've done was barfing all over me at GWT compile-time today:
Rebinding com.ryannorris.staffing.client.project.ProjectCreatorService
Invoking com.google.gwt.dev.javac.StandardGeneratorContext@9b32fe
Generating client proxy for remote service interface 'com.ryannorris.staffing.client.project.ProjectCreatorService'
[ERROR] com.ryannorris.staffing.client.Action<T> has no available instantiable subtypes. (reached via com.ryannorris.staffing.client.Action<T>)
[ERROR] subtype com.ryannorris.staffing.client.Action<T> is not instantiable
[ERROR] subtype com.ryannorris.staffing.client.project.ProjectCreatorAction is not assignable to 'com.google.gwt.user.client.rpc.IsSerializable' or 'java.io.Serializable' nor does it have a custom field serializer (reached via com.ryannorris.staffing.client.Action<T>)
[ERROR] com.ryannorris.staffing.client.project.ProjectCreatorAction is not assignable to 'com.google.gwt.user.client.rpc.IsSerializable' or 'java.io.Serializable' nor does it have a custom field serializer (reached via com.ryannorris.staffing.client.Action<T>)
I can't say I ever had the pleasure of dealing with this bit of attention to detail from the GWT Compiler in the past. And while I will readily admit I haven't read every change to the underlying architecture that comes with 2.0, this would seem to be a piece that might be worthy of some special mention.
It is, of course, nearly common sense to make sure that your RPC objects can go across the wire in the proper way, and thus simply respecting the semantics of java.io.Serializable the same way we would in EJB per se, is pretty reasonable. Just a little more heads up would have been nice.
Update 1: There seems to be some mention of fixing compiler feedback around RPC serialization here. But this defect doesn't suggest changes that might have actually altered behavior or requirements of the compiler since 1.7.
A Simple GWT Validation Framework Using Great Design Patterns and MVP
I've been writing a bit about Google Web Toolkit lately. It undeniably is disrupting traditional browser-based RIA development. But it does lack some features out of the box that most developers have grown accustomed to from frameworks like Flex and Ext. Field validation is one such feature. While the gwt-validation project exists to solve this very problem, an approach leveraging a good chunk of the existing GWT infrastructure can give you a robust, test-driven, and MVP-friendly approach for validation.
Does GWT Harkon the End of Javascript?
Javascript isn't going away. But neither are 1's and 0's. But one has to wonder what type of project or team that was looking to grow and build web-based, rich-client applications would actively choose to use Javascript on it's own now.
For my part, there's only so much patience I have taking on the burden of supporting multiple browsers and dealing with performance issues. Particularly if I'm Agile, and I'm focusing on delivering so much value so quickly, it's very hard to explain to a client that the underlying technology creates significant overhead that adds drag to the project. This is an even tougher sell - particularly when you're open with your client, when alternatives that meet the non-functional needs exist.
For your standard web applications that aren't as client-centric as today's RIA applications, it's certainly true that you are barking up the wrong tree with GWT. Rails, Grails, and Zend can all give you the non-enterprise delivery tools that accelerate development from the server-side and leave the Javascript problem to be solved in a less holistic, more tactical way.
But it's hard to argue now that anything short of the compilation semantics of GWT is useful in the RIA realm (without the need for a intermediate runtime, of course.) Javascript is too costly and too brittle in large-scale applications to be subject to human hands. If you've hired a contractor to build you a web-based RIA and they're not using GWT - it's well worth your wallet to ask them why.
Revenge of the Compiler – The Era of GWT and the Birth of Flash on the iPhone
For a while now, interpreted languages have reigned. They were fast to develop in, cheap to build teams around, and were less strict about the rules of the road than many of their more strongly-typed brethren. But as the modes of web application delivery have changed - indeed, as the modes of any sort of software delivery has changed - the era of the interpreter is likely in decline. As platforms are stretched to their limits and developers look for new ways to deploy high-performing, scalable web and mobile applications - an old friend emerges from the fog of battle to demonstrate why it was such a valuable innovation 50 years ago. Compiled software is back - this time to once again relegate a past generation of development platforms to the same museum as assembly.
Integrating Your QA Staff with Engineering in SCRUM
As much as I love automated testing, I have come to live with the fact that teams migrating from waterfall approaches to development to SCRUM often try to maintain the team structures they are familiar with. At times, this typically means an engineering staff that sucks at writing tests, and a QA staff that is still very much attuned to the finer grained edge and corner cases. Each of these parts of your team adds value to a SCRUM project. Integrating them to avoid bottlenecks, stay lean, and deliver with quality is a clever trick.
An Omniscient Learning Approach to Mock-based TDD
I recently posted about why I think mocks are simply the easiest way to get the most bang for your buck in automated software testing. But integrating it as part of a process is hard, and teaching it is even harder. Young developers seem to have a hard time grasping the idea of testing isolated units of code. I'll confess - for a long time, much of my unit testing involved setting up the appropriate test environments - Spring containers for persistence units, test databases, you name it. It's expensive to test this way, and there are only so many situations when integration tests are valuable. On lean, agile teams - code coverage isn't held in as high regard as having working software. On lean, agile teams - tests are a driver towards design, but they do need to be rooted in some level of initial thought on how a problem needs to be solved.
Piling on Praise for Apache Wicket
I think someone finally got a web framework for Java right.
While I'm still yet to try on some of the AJAX support - something that makes or breaks a web framework these days - Wicket's clear separation of concerns and robust architecture for MVP (right, 'P', as in Model-View-Presenter) has really impressed me. Generally speaking, I have not been one to embrace convention over configuration in frameworks like RoR, simply because it seems non-scalable. But given it's pure focus on UI and it's total flexibility to do whatever the hell I want with my middle tier, I'm feeling that when restricted to the presentation layer - the paradigm works. Wicket is pretty programmer-centric, so unlike RoR, you're not going to get off the ground without some skills or a scaffolding framework like Wicketopia, but I'm not at all convinced this isn't a bad thing.
There are a couple of things that I could get enthusiastic with around Wicket, were someone - including myself - to improve them.
- Documentation. Look, I hate documenting things as much as the next guy - but in as much as I've enjoyed the fruits of my labor in Wicket, I have not enjoyed chasing down information to all ends of the globe. I love the fact that this is working software, and the curve isn't too steep - but try finding stuff on form validation, or the entire concept of mounting URL paths.
- Callbacks, anyone? So, forms in Wicket generally appear to be processed by the onSubmit() method of the Form class. You override this in your child class of form. This is the very object-oriented way of doing things, but it seems a touch limiting out of the box to not be able to register callbacks on this method. My Form class exists so that I can have more than one of these per page, no doubt (take THAT ASP.NET), but I still think that I'd like to be able to actually register callback handlers as I wish in each Page, thus allowing Forms to have different behaviors dependent on where they are used. I'm pretty sure this isn't the 80% use case, but I still am left with only one alternative out of the box, and that's to keep extending the class hierarchy. It's nice to embrace strategy pattern and all, but to me this is where we really need an observer.
So I was able to fudge this myself by creating a FormSubmitListener interface, subclass Form and implement it's onSubmit() to call the formSubmitted() method from my new interface, it's own implementation registered through the constructor on my Form subclass - but I think in an MVP or MVC framework, I still would like the ability to use OOP to handle the quirks of the page lifecycle (yeah, yeah - Wicket is unmanaged), but allow observers to actually handle pseudo-user events.
These two things aside, I feel pretty at peace with Wicket as my web framework for Java projects going forward (sorry Seam).
Another note - I'm really interested in the possibilities of packaging all of the resources for the web project in the JAR file. While WAR's are fine for deployment, JAR's make the application open for truly modular design.
Now to refresh my memory on getting JTA running in a pure servlet container...
Mocks – the only thing separating complex TDD from value-added TDD
About two years back when I started getting completely fascist about test-driven development, the complexity was always "gee, i have an application container and I need to involve it in my unit tests so that I can get full test coverage !!111oneeleventy."
This typically meant providing a real collaborator, like a PersistenceUnit in Java, so that I could test trivial operations like persisting an entity. At the time, I challenged a manager on this:
What are we really testing? Are we testing OUR requirement, or are we testing something we should reasonably expect Hibernate to do on the basis of our initial technology selection?
Code coverage I believe is pretty overrated. No one cares whether or not you can prove your method to persist an entity works because the developers of Hibernate/TopLink/LINQ to SQL have already proved this through their unit tests. What you are building when you write a test that actually checks the database to see if your middleware used a pre-packaged object-relational manpping framework correctly is an integration test. There's certainly value to integration testing with data access layers, particularly when difficult to test components of your middleware (like stored procedures and triggers) are involved. Saving that however, the focus of test-driven development - namely unit tests, should be on the business logic that is proprietary to your applicatiom, be it the front-end or the middle tier.
Now, suffice to say that to a good number of developers and architects this isn't news, but if you really want to isolate the code which you wrote that is specific to your business rules and requirements - mocking frameworks are the way to go. Particularly in an Agile project where we can readily identify certain injected dependencies (like an EntityManager, for example) as a collaborator of the class under test, your unit test is really interested in asking the question based on this interaction with this external component, how should I expect my logic to react?
In these scenarios of course, I mock or stub the EntityManager. In the past, a fool like me would have tried to load a container within my unit test environment. This is actually an integration test, in addition to the fact that it is costly and doesn't add the value a truly isolated unit test which focuses on the code you wrote does.
In .Net, RhinoMocks is scalding hot with it's supprt for mocking through lambda's. In JEE, I've fallen in love with Mockito.
So, stop worrying about how you can get JBoss running so that your CI environment can execute inside of it. Instead, use mocks to give your code the resources it needs to vet out the conditions in your own code that you want to test.
Diving back into Java, and liking it (mostly)
So for various reasons, I've pulled Eclipse Ganymede down and decided to check in on where Java has gone during my year-long mental hiatus in Redmond. I have certain biases now from the land of .Net, and god help the Java world if it angers me after seeing the things I've seen in the last year.
All in all, I'm very pleased.
The m2eclipse plugin is marvelous, finally.
The day has finally come where I'm no longer fighting Eclipse to build projects using Maven, as it should be. Maven ties far too many niceties of the world together, and to not have it as the underlying, portable build tool within the IDE has always frustrated me. The ability to quickly start a new Maven project, apply an archetype and go is fantastic. The fact that it doesn't require special jazz to get a WTP project up and running is even better.
Hey look, working with my database and some JPA implementation is really easy!
...well, almost easy. I created a project for my middleware just using the quickstart archetype. I was just going to throw Spring on top of it and avoid spoiling the good experience so far with EJB insanity. The next thing I wanted to do was load up my database tables as ORM classes via Hibernate.
For whatever reason, this was cool on my Mac. Project Properties...JPA Tools...Generate entities. This is somehow not the way to do it over in windows. So instead I tried to add JPA as a project facet.
My first problem was that I didn't have Hibernate set up as my default JPA provider. Unfortunately, you can only do this through the Maven-managed dependencies. It has to be an Eclipse user library. So I download the Entity Manager and wire it up into Eclipse. Add the Java Facet (somehow not a default, probably Maven's fault), added the JPA Facet (and am told I need to add the Utility Facet, so I do that).
Further configuration required.
Ok. So I click into this further configuration and it reasonably wants to know how I connect to the database. Fair enough. I do all this, and it still won't let me apply the change.
Eventually, it appears you need to add the Java project facet first, and then and only then can I reopen the properties page and apply the JPA facet. A frustration point, but I figured it out.
Hey, nothing special to get a project with the Wicket archetype running in WTP.
I start a separate web project and use the Wicket archetype, interested in tackling what looks to be a nice, lightweight UI package for Java (though it looks like Spring integration isn't trivial - which is basically unacceptable these days). I start the project, I add a server configuration, and deploy...
Holy crap, it works out of the box!
I have a ways to go, but things feel more turnkey with Eclipse than I've ever experienced. I did up some JUnits with Mockito, and that was easy, indicating that if I were to set up Cruise or some other CI tool, I could quickly get going with a full Agile project. Exciting stuff.