The title says it all. I have moved Model Architecture to WordPress and a custom domain to better support my growing needs. There are many sites on how to port from blogger to WordPress, but the long and short of it is that there is a build in importer in the admin site for your wordpress blog so it take about 3 minutes as long as you have a “newer/modern” blogger account. I did so, 3 minutes later it was done.
(Just a screenshot of where it is located)
This post builds on previous posts and is serves as additional commentary and context to a post by Franco Civello - UML for MDD – Oxymoron or match made in heaven? Not sure what Model-Driven Development (MDD) is exactly, then check out IBM’s MDD Redbook which is one perspective.
UML is a modeling language with thousands of features and facets. Most people discount UML, even experienced modelers and language developers, without understanding what the language is capable off. The primary UML feature missed of importance here is the UML Profiles capability. People miss that UML Profiles allow for extension and constraints of the language itself, read section 18 of the UML Superstructure or take a look at the UML profile catalog. The two linked posts (1,2) speak to what UML profiles are etc, so you might consider reading them before proceeding. This extension and constraint mechanism is exactly what is needed to create domain specific models i.e. support MDD.
Now MDD is just a process, so what are the actual implementations or tooling used? The following are just examples and it is not complete as I am sure there are a hundred ways to do it. Firstly, there are DSL (Domain Specific Language) tool kits. A classic example would be YACC and LEX, but a modern example is Eclipse XText Model/Language Definition. Another significant way is with DSM (Domain Specific Modeling) tool kits, such as Eclipse EMF or MetaEdit+ (a leader in the DSM space). The DSM space is not free from it’s challenges too, but they are further along on average. Think of DSMs as graphically represented DSLs if you are newer to this area. Finally UML Profiles are another way to implement the domain specific tooling required. Tools such as Rational Software Modeler (RSA/RSM), Eclipse MDT, and other tools.
What adds to the confusion between DSL/DSM and UML Profiles when it comes to the creation of domain models for MDD processes is approach and familiarity. The good DSL/DSM tools typically are tabla rasa (blank slate) model creation, much like a empty file when you start programming. There is less baggage by starting with a blank slate, you also do not have to worry about removing or limiting existing model elements. Now strictly speaking for UML Profiles you can start with a basically blank slate, but most tools don’t support this. A modeler in the UML Profile space must not only construct/extend the model, but constrain the other model elements that are not needed or conflict with the DSM. You also have to research and pick the right UML element type to extend to minimize the constraining work you have to do. Interestingly, in my experience creating small DSMs/logical constructs for a group of architects having a rich language actually reduces the work, but this need not always be the case.
You could really do MDD with any of the tools above, the question often becomes what is the cost, time, and skill level needed by the resources? What actually seperates the tools are the features and ease of rolling out model tooling to all of the involved parties, such as business, vendors, developers, etc. So the seven hundred pound gorilla in the room is actually the lack of wide spread usable tooling to build UML Profiles. Few tools if any implement all of the UML Profile features and creating tooling for use in the MDD process can be very difficult. I suspect most people use free or drawing oriented UML tools and thus never get exposure to UML Profiles. Even if they did they would have to buy a specific software suite to support it fulling. I use Rational Software Modeler (RSM/RSA) which is thousands of dollars and even it does not correctly implement UML Profiles, but it is close. The DSM tools are not all free, but at least there is Eclipse MDT with EMF/GMF and the generative tools needed. In a year or two Eclipse may have an offering that is usable enough for novices and support UML Profiles for the tooling efforts more fully.
So UML and MDD go together just fine when you understand the extension, constraining, and profiling capabilities of the language, but all is not well with the union. UML requires lots of time and energy to learn and understand it before it will begin yielding results. Better cheap tooling and tutorials are still needed to support the modeling and programming communities at large lest UML/MDD/MDA remain for ‘experts only’ which I would quantify as a failure by it’s advocates. Much of these challenges are not just limited to a UML Profiles based approach to MDD.
It is worth noting that at some point the industry should look back to Case Tools and YACC/Lex to evaluate why Domain Specific movements have failed in the past, or we may just repeat it.
Tonight I tried to find quick reference sheets for both UML and BPMN, free of course. There are quite a fewer different terms for them be it poster, reference cards, cheat sheets, quick guides etc. However, once I got into several sites by searching for “Reference Cards” I found the other names for these small printable guides to various technologies. Oh yes, and much more managable or likely to be used than “pocket references” which don’t fit in your pocket.
List of quality sites quick guides:
I did not find a suitable quality UML guide (Stackoverflow has a list), but the BPMN poster at itPoster.net though outdated at time of this post was still really well done. There are several red herring links which get referenced a lot, but are not that good, ex: (How are you to carry this around?) Any other good sites that have a listing of printable reference guides?
Connecting UML Components with the Ball and Socket notation in Rational Software Modeler (RSM/RSA) and Eclipse UML2 Tools is not fully implemented or flawed. Too fully understand my point you have to keep in mind that these tools are for modeling, not just drawing a picture/diagram. Thus the internal model representation of what you diagram must be correct and complete.
“As a result, components and subsystems can be flexibly reused and replaced byconnecting (“wiring”) them together via their provided and required interfaces….In addition, the BasicComponents package defines specialized connectors for ‘wiring’ components together based on interface compatibility.”
“The connector concept is extended in the Com ponents package to include interface based constraints and notation.A delegation connector is a connector that links the external contract of a component (as specified by its ports) to the internal realization of that behavior by the component’s parts. It represents the forwarding of signals (operation requests and events): a signal that arrives at a port that has a delegation connector to a part or to another port will be passed on to that target for handling.An assembly connector is a connector between two components that defines that one component provides the services that another component requires. An assembly connector is a connector that is defined from a required interface or port to a provided interface or port.”
“[5] An assembly connector must only be defined from a required Interface or Ports to a provided Interface or Port.”
I have to admit that I am lured into the pocket size form factor used by O’Reilly and others. The cute baby animals on the cover, like the gorilla on the front of the “UML 2.0 – Pocket Reference“ is just fun. I also have “The Elements of UML Style“ in the same easy to consume and not really pocket sized size. Parts of this review also apply to both pocket books, but the majority is about the UML 2.0 – Pocket Reference.
If you do actually end up bringing this “pocket” reference around with you then great, but consider when will you actually use it. While you are walking around the park thinking about UML and all of its confusing details? This book only covers syntax and usage, not really semantics which is where most people struggle anyhow, as the semantics and detailed syntax consume over 1000 pages. You could bring it to meetings and wow people with perfect diagrams. Again, this book might help with that, but how often are you drawing a diagram on the white board and everyone is confused because you lines are not specific enough, or the shape is just not right. This does not happen because the people in the meeting have the context of the conversation and thus do not need perfection, the drawing is just a tool to move the conversation forward not get hung up on syntax, semantic maybe, but this book won’t help with that beyond the bare surface.
The short lesson: When looking at eclipse features dig deep and work off the website and examples. Books are outdated quickly and are often written to just the major usage of a package or feature. Never be to proud to use the eclipse project specific mailing list.
The story: Whenever I take time off work, I invariably take on creating some new thing or read a technical book, basically just go down a rabbit hole of some kind as much of my day to day work requires abstraction from the details and hands on coding.
The Christmas 2009 break is no different. This time I dug a little deeper than I normally do with eclipse and plug-ins. I have been creating an eclipse plug-in to import UML objects from an outside server which houses use cases, requirements, and test cases. I figure why copy and paste or manually sync them which you can have a wizard done. Great so after a COM Bridge, EMF Transactions, UML Profile, and a shovel I have an import working. I did not do this in a vacuum, but instead have been going off, eclipse books, the eclipse.org dev websites etc. I had checked into Eclipse Team about 8 months back and found it was decidedly IResource (File/Folder/Project/WorkspaceRoot) limited as all of the methods seem to require IResource to operate. This lead me to just drop the “Syncronization” and Team approach to integrating UML models with outside data sources. Heck I figure even IBMs Rational suite has to do all the sub-file (UML object) comparisons with a comparitor, that must be it.
As I completed a workable Alpha of the importing plug-in and began to lust after the export, update, and delta features one expects when collaborating, I decided to double check that the Eclipse Team (CVS,SVN, etc) really would not work. Into the rabbit hole I went. This time as I went to the website and played with examples. They all showed promise as features had been added in recent releases. The org.eclipse.team.examples code is helpful for understanding this seriously complex package/feature. But more importantly there had been additions since 3.2 and how there seemed to be support for Logical Models. Great models are what I am doing.
So I really dig in. The trouble was that I cannot find a good example to how this would be done in a non trivial way. The example Logical Model code was trivial as each “Model Element” was still a IResource, so it did not show that this could be done. Even though they had in the API/Eclipse documentation mentioned Ecore models it all seemed to be still focused on IResources. Finally, however, I am convinced that the Logical Model Team feature set will meet the need of Syncing non-IResource model components, ie sub-file detail level representation. The wiki page about the team logical model objective said it most clearly.
The following paragraph, taken from the Eclipse 3.2 plan, describes the motivation for the logical model integration support that was added in Eclipse 3.2.
The Eclipse Platform supports a strong physical view of projects, files, and folders in the workspace. However, there are many situations where a physical view is not the most salient or useful for many purposes. In some cases, multiple distinct objects happen to be stored in a single file, like an archive. Conversely, in other cases, something that is logically a single object is stored across multiple files. This discrepancy between logical and physical creates problems for common operations such as searching, comparing, and versioning, which need to work in the physical realm. Eclipse should support some way of mapping between a logical view and the physical organization of files on disk.
At the beginning of the 3.2 development cycle, we captured the requirements from several clients in a requirements document.
And while I was writing this post I found THE emf example that has not been merged in with the other org.eclipse.team.examples, seriously, I can’t even find an email dev list to post about this issue. Also, the link on that page is dead, I found the code in the CVS archive however.
So, hours of playing with the examples, running them in the debugger trying to figure out the slight of hand and object types being used, and reading pages of seemingly contradictory documentation, nearly giving up assuming that it must not work, only to search or dig just a little bit more and find out it is supported. I know way more about the Team feature set now then I actually need to know for writing the plug-in. Hopefully next time I will navigate the eclipse web a little more efficiently, or I am find a mailing list and enlist the help of others rather than just digging deeper into my rabbit hole alone, and even Google Search failed me.
I like most people, I suspect, especially software architects and programmers, dream of white boards on every wall floor to ceiling. I have wanted this for some time for my office so I could doodle hours away in my office getting dizzy on the dry erase fumes. In the past I had looked for a quality product and failed, until now. Visiting my undergraduate college (St. Olaf) the computer science for it’s brand new shared building has for entire rooms painted a white board surface onto the walls. STUNNING! Want to convey an idea, design a group project, doodle, noodle, or whatever, just walk up to a wall. I hope it holds up and I hope to get around to painting my office soon. I think they are using one of the more expensive products, IdeaBoard, but I am emailing the school to double check.
Finally a canvas large enough to hold all of the crazy UML diagrams and brainstorms.
Martin Fowler and Markus Völter on DSLs – JAOO Conference Somewhat interesting discussion by some DSL leaders. There is a small bias around a specific vendor’s software, but interesting to listen too.
What they talked about, my notes:
DSLs:
Eclipse GMF/EMF/Textual Languages
CASE Tools, COBOL, Fantasy that programmers are not needed.
Levels of DSL/DSM tooling – Documentation/Testing/Execution
Custom Syntax (External DSL) vs Internal Syntax (Internal DSL , Lisp/Ruby)
Method Chaining, Cool!
1 notation or many notations
(Excel, Boxes and Lines, etc) Power in how to combine the notations.
Divergence, Experimentation, and then Convergence.
UML is not a factor, so they think.
Here is the book in progress that Martin Fowler references, it was in draft form at time of my writing this post. Fowler’s DSL book draft
I have followed the DSM (Domain specific modeling) happenings online for sometime now and at best the community is scattered and most discussions/happenings limited to conferences. However, the DSMForum.org pulls this information together for easy consumption. Don’t be fooled by the dated last century website design, all nerdy modeling website look that way. The DSM Publications page provides the best set of links for DSMs on the web, including podcast, conferences, and papers. Dispite one of the co-founders working for MetaCase a tool I am not currently focusing I found their coverage not too biased.
The tools page they provide is nearly accurate, playing down eclipse and rational contributions a little bit, but the list represents the major players to my knowledge. RSM/RSA now has a UML Profile Tooling capability and eclipse GMF has beta WYSISYG editor the list could use rework, but a minor complaint.
They also have a Linked-in group, although it is not that active.
I am voting earth, this blog post is my digital post for balance. You don’t have to eat grass and walk to work to be green. Tonight I will go for a walk at 8:30 once the lights are turned off and then play cards, heck I won’t have to code/program. I enjoy life, and I do it smart, they are not XOR or mutually exclusive.
The phrase reduce, reuse, recycle is in order for a reason.
1. Reduce your consumption: If a person were to buy an H2 Hummer maintain it and drive it for a life time it would be better for the environment than a person who buys a new hybrid every time it comes out. The most expensive part of a car environmentally is typically its construction, assuming it is maintained (ya know keeps a muffler). I buy quality items that will last a long time so I am buying fewer things. I also make an effort to buy fewer things in general, less to clutter my house and the landfills. Like tonight at 8:30 I am turning the lights/heater out. Don’t accept the free printers that come with computers unless you need it. I have 3 in my office right now that people gave me when they got new free ones. They still worked and have ink. Don’t always fall into the trap of buying a new energy efficient thing and
The interesting thing about the economic down turn is that I suspect in general it is good for the environment as more people figure out how not to buy things they don’t really need. Think about cars the most complex common commodity off late years production/sales by 40-50%. That means fewer new cars built hurting the environment and more local repairs to maintain existing cars.
2. Reuse: I buy used cars and maintain them, they are quality cars that will last a long time. Stretch a computer out another year by replacing the one slow component like a graphics card or the memory. Turn down the heat in your house and turn up the heat near you with blankets etc. In the summer get used to warmer temps and use a low power fan to maximize cool air. Give away what is still good shape or EBay.
3. Recycle: Finally when you can keep something no longer and no one else wants it then do the right thing and recycle what you can. Be reasonable at least. If dell offers free or near free recycling for computers do it. Save your electronics for free events that are offered once a year, at least in the us.
