Objects by Design Forums Here you can view your subscribed threads, work with private messages and edit your profile and preferences Registration is free! Calendar Find other members Frequently Asked Questions Search Home  
Objects by Design Forums : Powered by vBulletin version 2.3.5 Objects by Design Forums > Main Forums > UML Questions > Agile modeling
  Last Thread   Next Thread
Author
Thread Post New Thread    Post A Reply
rao_battula
Junior Member

Registered: Nov 2002
Location: Hyderabad
Posts: 10

Agile modeling

Hi guys,
Agile modeling is also talking about iterative and incremental development. They specify "AM deals with the changing requirements by embracing change, but taking an incremental approach to development, by seeking rapid feedback and insisting on active participation of stake holders, so that requirements may be quickly explored." I am little bit confused about the above statement. How RUP and EUP are doing in that case.

According to me RUP also follows iterative and incremental approach. And use case analysis emphasizes on active stake holder participation. Then how is AM different from RUP.

Report this post to a moderator | IP: Logged

Old Post 12-10-2002 03:42 AM
rao_battula is offline Click Here to See the Profile for rao_battula Click here to Send rao_battula a Private Message Find more posts by rao_battula Add rao_battula to your buddy list Edit/Delete Message Reply w/Quote
SZ
Administrator

Registered: Apr 2001
Location: New York
Posts: 492

Good question.

The best way to answer this is to point you to Scott Ambler's essay on AM and RUP at the Agile Modeling web site.

In essence, from what I have read so far, AM is similar to XP in that you can apply some minimum subset of modeling to an iteration based on what works best. This is somewhat different from RUP which emphasizes more comprehensive workflows for each iteration.

Be aware that the Agile Modeling web site appears to be largely the work of Scott Ambler. There will be other innovators who adapt the use of UML to XP processes. Craig Larman, for one, should be expected to respond since he has shown interest in XP. The response of UML authors has been a little slow in coming on the topic of XP, however, so Scott has taken a lead. He has published a book called Agile Modeling which has received very positive reviews on amazon.com.

Report this post to a moderator | IP: Logged

Old Post 12-11-2002 02:02 AM
SZ is offline Click Here to See the Profile for SZ Click here to Send SZ a Private Message Visit SZ's homepage! Find more posts by SZ Add SZ to your buddy list Edit/Delete Message Reply w/Quote
rao_battula
Junior Member

Registered: Nov 2002
Location: Hyderabad
Posts: 10

Hi SZ,

Thank you for the response.

In his book "Object Oriented Analysis and Design with applications", Booch insists on highly iterative and incremental approach and also talks about design driven approach not document driven approach. And also suggests some responsible role to the developer. I found same concepts in AM... I think AM is reteaching the same concepts, may be with better explanation.

AM and XP supporters assume that RUP has only one tool, "usecases" to grab requirements. I do not think its true. I once read in Rationaledge magazine( I will let you know the edition in my next post), where the author suggested different methods to different types of systems. Even Booch suggesting us to use one of use-case analysis, behaviourial analysis, classic approaches, domain analysis and CRC card techniques. Chosing a technique to grab requirements is highly depending on type of the system and intellectuality of the team. No process can set a rule in this concern.

Let me know your views regarding the above.

BSR

Report this post to a moderator | IP: Logged

Old Post 12-11-2002 03:11 AM
rao_battula is offline Click Here to See the Profile for rao_battula Click here to Send rao_battula a Private Message Find more posts by rao_battula Add rao_battula to your buddy list Edit/Delete Message Reply w/Quote
Scott Ambler
Senior Member

Registered: Dec 2002
Location: Just North of Toronto, Canada
Posts: 31

Agile Modeling and RUP

The principles and practices of AM can be used to improve the effectiveness of your modeling and documentation efforts on a RUP project.

Differences:
1. The RUP is a full-fledged methodology whereas AM focuses only on modeling and documentation.
2. RUP isn't necessarily instantiated in an agile manner, in fact it rarely is. AM on the other hand is always instantiated in an agile manner (otherwise you're not doing AM).
3. RUP is prescriptive. AM is chaordic.

The best way to gain an understanding of AM is to:
1. Visit www.agilemodeling.com
2. Read the AM book (www.ambysoft.com/agileModeling.html)
3. Join the AM discussion list (www.agilemodeling.com/feedback.htm) and simply ask questions

- Scott

__________________
Scott W. Ambler

Report this post to a moderator | IP: Logged

Old Post 12-17-2002 07:39 PM
Scott Ambler is offline Click Here to See the Profile for Scott Ambler Click here to Send Scott Ambler a Private Message Visit Scott Ambler's homepage! Find more posts by Scott Ambler Add Scott Ambler to your buddy list Edit/Delete Message Reply w/Quote
SZ
Administrator

Registered: Apr 2001
Location: New York
Posts: 492

Craig Larman on Agile Modeling

We asked Craig Larman about his involvement with agile modeling and he wrote back with some interesting history and insights on the subject:


I'll share a bit of my history with agile modeling, in response to a late '2002 question about my current public inactivity on this subject:


Scott deserves credit for pulling this information together, but I know he will acknowledge that these are older practices. For a brief history on the name: he emailed me some years back with the idea of calling this "extreme modeling" as a presentation of how modeling is done in XP. However (having earlier discussed with Kent in some detail his vision of modeling in XP), I suspected it was not how Kent wanted modeling in XP, although I was supportive of the underlying modeling approach Scott was advocating, as it corresponded with mine. Then Scott, Kent Beck, Ron Jeffries, me, and Bob Martin had an email exchange on this question, and that the name "extreme modeling" was not best as the approach didn't reflect XP's view on modeling. Thus, if I recall, Bob suggested "agile modeling" instead, and the name stuck.


To pick up on the "older ideas..." point, I've been sharing & coaching on lightweight low-tech high-touch diagramming and UML for all projects since the '80s, and specifically in the context of XP, RUP, and agile modeling (before it was named as such) for around 5 years.


I've been coaching with a combination of UP, Scrum, and XP practices since '98 when it was word-of-mouth; UP and XP were making the buzz or seminar circuit then. And my OOA/D seminars, courses, and consulting have always stressed this "agile" approach in the context of a short iterative lifecycle processes, since '88. And it's how we as a company at ObjectSpace, where I worked in the early-mid 90s, practiced modeling in the context of development; when under our control we did projects using 3-4 week timeboxed iterations in common project rooms with
floor-ceiling whiteboard spaces to maximize agile modeling and visual communication of project information.


To quote a Jan 2002 review at Amazon of my 1st edition Applying book, "IMHO this book is an Agile Modeling book written before Agile Modeling became vogue." Definitely that was my vision when I wrote it in '95-96. the 2nd edition Applying... chapter 35 "on drawing" summarizes some agile modeling practices related to UML.


Note that the motivation for this agile approach to modeling was not then, nor now, a response to high-pressure delivery dates or web dev; rather, it was and is simply what I have called a "human nature based sustainable" development approach. I grew up in software dev in the 70s, and saw first hand and repeatedly the failure of "formal" and "thorough" modeling theories from SA/SD, etc. It didn't match with the psychology of developers, or the business context, and the practices didn't stick; what the books and courses advised didn't match what later happened in IT departments. In the mid 80s I saw the failure of CASE and lots of fussy, detailed drawing/design work. And I focused on doing AI and expert systems dev with ES-influenced knowledge acquisition, prototyping, and modeling practices in the early 80s. It was those experiences that shaped my practice for "light high-touch low-tech" (as I called it then) practices, such as hand drawing using lots of whiteboards in a common room, short modeling sessions followed by short dev cycles, parallel model drawing on diff whiteboards, printing whiteboards, and so forth.


Note that some folks have read the Applying book thinking I was an advocate of detailed upfront modeling or design, as the book introduces OOA/D and diagramming, but that's not the case. It's just that the book is emphasizing one part of the larger picture, and is presenting a suite or "intellectual toolbox" of practices that can optionally be applied. When I coach a team, I've sometimes gotten a surprised reaction from clients when I come in on day 1 and suggest "let's start programming by tomorrow" or "let's not bother with doing model X" or "let's avoid using that CASE tool and stick to the white boards." They have a kind of guilt that they haven't done enough modeling or used a CASE tool, when in reality the problem is analysis paralysis, low value diagramming, an unskillful build environment, not enough testing, ...


Thus, my seminars and consulting/coaching approach on "agile modeling," agile UP, UP with XP and Scrum, etc has been delivered since '98 both at conferences and to many orgs--usually mgmt groups. In my role as director of process at Valtech (an international, French-based company), in '99 we adopted globally "light UP" (as we called it) that combined these practices. One could have visited my "UP Distilled: Lightweight UP and Modeling with XP Practices" seminar at SD West in '98 (or was it
'99; now I forget).


Also, at a number of conferences in the late 90s and 2000, I participated in panels with kent/ron/martin/bob on this topic, and RUP vs XP or RUP + XP.


With all this UP + XP + agile modeling activity in the late '90s I assumed (incorrectly) that the ideas/practices and combination were thus well known by now in the market, but it seems new generations keep revisiting the topic, which is good, as it's an important topic. So, the subject is a slightly old one for me, and thus hasn't interested me to rehash it. And, Scott did a nice job of summarizing the practices both he and I have been promoting for years (which is why I wrote the blurb on the cover of his book).


regards, craig

Report this post to a moderator | IP: Logged

Old Post 12-17-2002 11:36 PM
SZ is offline Click Here to See the Profile for SZ Click here to Send SZ a Private Message Visit SZ's homepage! Find more posts by SZ Add SZ to your buddy list Edit/Delete Message Reply w/Quote
sduskis
Member

Registered: Apr 2001
Location: Monsey, NY
Posts: 33

"Agile" Modeling

Mr. Ambler,

Thank you very much for posting here! I'm a big fan.

With all due respect, I'd like to expand the meaning of "Agile Modeling" from a Scott Ambler implementation to a set of implementations of software software modeling that subscribe to the Agile Software Development philosophies.

The Agile Alliance, the Agile Software Development flagship website, has some wonderful articles on UML, Modeling and Design in an agile fashion. Mr. Ambler is the main contributor to the modeling articles.

Report this post to a moderator | IP: Logged

Old Post 12-18-2002 08:35 PM
sduskis is offline Click Here to See the Profile for sduskis Click here to Send sduskis a Private Message Find more posts by sduskis Add sduskis to your buddy list Edit/Delete Message Reply w/Quote
Scott Ambler
Senior Member

Registered: Dec 2002
Location: Just North of Toronto, Canada
Posts: 31

Agile Modeling

In what ways do you think that AM does not subscribe to the values and principles of the Agile Alliance?

- Scott

__________________
Scott W. Ambler

Report this post to a moderator | IP: Logged

Old Post 12-18-2002 11:14 PM
Scott Ambler is offline Click Here to See the Profile for Scott Ambler Click here to Send Scott Ambler a Private Message Visit Scott Ambler's homepage! Find more posts by Scott Ambler Add Scott Ambler to your buddy list Edit/Delete Message Reply w/Quote
SZ
Administrator

Registered: Apr 2001
Location: New York
Posts: 492

more good agile modeling books

I think what sduskis is saying is basically that Agile Modeling, in order to grow as a technology, should be independant of any one contributor. This is how the UML grew into a standard under the umbrella organization of the OMG, which worked with a wide range of industry leading companies. It has thus become an 'open' standard.

For Agile Modeling to grow as an 'open' standard, it would make sense to gain similar wide-spread industry participation. Currently Agile Modeling appears to be the work of primarily one person, Scott Ambler. I don't know if this is the intent or not.

As an example of other object technologists who have contributed to the agile modeling effort we found these two highly recommended books:

Agile Software Development, Principles, Patterns, and Practices by Robert Cecil Martin

Agile Software Development by Alistair Cockburn

If anybody knows of any other good titles, please add them to this thread.

Report this post to a moderator | IP: Logged

Old Post 12-19-2002 04:07 AM
SZ is offline Click Here to See the Profile for SZ Click here to Send SZ a Private Message Visit SZ's homepage! Find more posts by SZ Add SZ to your buddy list Edit/Delete Message Reply w/Quote
Scott Ambler
Senior Member

Registered: Dec 2002
Location: Just North of Toronto, Canada
Posts: 31

Agile Modeling

I suppose it could look like that to an outsider, but it's not the case. I'm more the thought leader, not the sole contributor. At the very start I went to great lengths to get input from people, hence the web site and Agile Modeling mailing list, and conference workshops.

An earlier post quotes Craig Larman as he references the fact that several people, including himself and Bob Martin, contributed to AM in the early days. It was actually several hundred people, and that took part on the AM list (the Extreme Modeling list at the time). Bob Martin actually named the technique, as Craig mentioned. More importantly, many people had input into the development of the method, there is one heck of a long list of names at the beginning of the book attesting to this fact, and people still contribute to it via the Agile Modeling mailing list (visit www.agilemodeling.com/feedback.htm for details).

Several books have been written discussing the application and tailoring of AM. This include The Practical Guide to XP (http://www.amazon.com/exec/obidos/ASIN/0130674826), Sams Teach Yourself Extreme Programming in 24 Hours (http://www.amazon.com/exec/obidos/ASIN/0672324415), and the forthcoming Test Driven Development by Dave Astels. I have no doubt that there are other books underway that I don't know about.

Other people are writing papers about applying AM in practice, papers that I hope to link to once they're online.

Other methodologists are clearly welcome to contribute to AM, and do in fact do so. Did you have any ideas regarding how I could be more open with AM? If so, why don't you post them either here or on the AM mailing list and get a conversation going?

- Scott

__________________
Scott W. Ambler

Report this post to a moderator | IP: Logged

Old Post 12-19-2002 11:32 AM
Scott Ambler is offline Click Here to See the Profile for Scott Ambler Click here to Send Scott Ambler a Private Message Visit Scott Ambler's homepage! Find more posts by Scott Ambler Add Scott Ambler to your buddy list Edit/Delete Message Reply w/Quote
SZ
Administrator

Registered: Apr 2001
Location: New York
Posts: 492

I guess the most obvious suggestion is to submit a draft of the Agile Modeling guidelines to the OMG and align them with the UML family of specifications. The OMG has a guideline to the specification process on their site.

While pushing this through the OMG may seem to be the antithesis of 'agile', nevertheless, the end result will be a set of best practices for object-oriented modeling which is aligned with the industry standard UML specifications.

One example benefit is synergy with the emerging MDA - model driven architecture - work being done by the OMG and UML tool vendors. For example, if a UML model for an EJB 2.0 application can be used to generate a large part of the code (persistence, transactions, etc.) then couldn't this be considered 'agile modeling'?

The other obvious benefit is that the many participating members of the OMG could contribute their insights to the AM process. Since these include many employees of UML tool vendors, they would be in a better position to bring some of the AM work back to their products. You can see an example of this type of synergy with Gentleware's XMI extensions for UML 2.0.

This sounds like an obvious win to me. What do you think?

Report this post to a moderator | IP: Logged

Old Post 12-19-2002 11:53 AM
SZ is offline Click Here to See the Profile for SZ Click here to Send SZ a Private Message Visit SZ's homepage! Find more posts by SZ Add SZ to your buddy list Edit/Delete Message Reply w/Quote
sduskis
Member

Registered: Apr 2001
Location: Monsey, NY
Posts: 33

quote:
In what ways do you think that AM does not subscribe to the values and principles of the Agile Alliance?


Mr. Ambler,

Please let me clarify. In no way am I suggesting that AM is not Agile.

I am a big fan of your work and the work done by the Agile Modeling community.

The Agile Modeling website is a fantastic source for discussions of documentation and modeling in an Agile fashion.

However, AM is focused on a subsection of the software cycle.

The initial post in this thread compared AM to RUP. Your post indicated that the comparison is unfair. A better comparison would be RUP to Agile Software Development philosophies and its varied practices. There is a plethora of articles comparing Agile philosophies and implementations with RUP on the Agile Alliance website.

I suggest that the primary source and starting point for discussions on everything Agile, including specific focuses, is the implementation and focus agnostic Agile Alliance website.

Your posts didnít have an Agile Alliance presence. Your site has a strong Scott Ambler brand.

SZ,

Mr. Ambler does have an article on MDA.

Last edited by sduskis on 12-19-2002 at 01:37 PM

Report this post to a moderator | IP: Logged

Old Post 12-19-2002 01:05 PM
sduskis is offline Click Here to See the Profile for sduskis Click here to Send sduskis a Private Message Find more posts by sduskis Add sduskis to your buddy list Edit/Delete Message Reply w/Quote
Scott Ambler
Senior Member

Registered: Dec 2002
Location: Just North of Toronto, Canada
Posts: 31

Sduskis, I agree!

www.agilealliance.org is definitely a better starting point for learning about agility, and AM is only one of many agile processes.

I'd rather compare RUP with agile processes, such as XP, FDD, or DSDM, not the values & principles of the alliance. That way you're comparing processes with processes.

SZ,
The OMG is completely and utterly the wrong place for AM. If there was an agile standards body, which I don't think we'll see for a long time if ever, I'd be happy to turn it over to them.

The values, principles, and practices of AM are completely orthogonal to the UML -- you can apply AM without the UML, I do it all the time, and you can clearly use the UML in a very non-agile way. Of course, my advice (www.agilemodeling.com/essays/realisticUML.htm) is that the UML should form the core of your modeling techniques. Unfortunately the UML is not complete, I would prefer that the OMG focus on that, so the members of the OMG have a lot to keep themselves busy.

Speaking about the MDA, as you can tell I'm not much of a fan of it. Sounds great in theory, but I just don't see practitioners giving a hoot about it. I'm all for really effective tools, see http://www.agilemodeling.com/essays/simpleTools.htm, and eagerly await tools that actually provide value to real-world practitioners. Some tools exist like this, but they're few and far between.

- Scott

__________________
Scott W. Ambler

Report this post to a moderator | IP: Logged

Old Post 12-19-2002 01:32 PM
Scott Ambler is offline Click Here to See the Profile for Scott Ambler Click here to Send Scott Ambler a Private Message Visit Scott Ambler's homepage! Find more posts by Scott Ambler Add Scott Ambler to your buddy list Edit/Delete Message Reply w/Quote
SZ
Administrator

Registered: Apr 2001
Location: New York
Posts: 492

Poseidon and Extreme Modeling

Welcome to Extreme Modeling (XM)...

I have to hand it to Marko Boger, founder of Gentleware, a German based company which has extended the open-source ArgoUML project, for living up to the Gentleware motto of developing differently.

Dr. Boger has taken a very different approach to XP than Agile Modeling has taken. His background as a CEO of a leading UML tool company with a PhD in Computer Science gives him the ideal credentials to take on the task of proving that XP and modeling can work together without compromise on either side. For details on his vision see What is Extreme Modeling?.

Essentially, XM says that you can build testability into UML models through the use of simulation. Now this is not necessarily his innovation. The real-time and embedded system folks have been doing this for a while. They use UML tools to create state chart diagrams that are then fed into simulations and finally used to generate all the code for the implementation. For more details, see the article on the OBD site, OO CASE Tools for R-T/E Development by H.S. Lahman.

Note that Richard Soley, CEO of the OMG is on the Gentleware board of directors. Also note that the OMG's MDA, model-driven architecture, is a part of the Gentleware vision. With their portfolio of plug-ins for Poseidon UML, they have already extended UML into new categories of functionality, so MDA is not just a vision for them. They are building it today.

It puzzles us why Scott Ambler is so skeptical of MDA. He must know of these real-time UML tool capabilities. This stuff is working today, albeit in a specialized field. Granted there will be a lot of marketing fluff and hype surrounding the MDA. But open-source software cuts through the hype and makes things happen.

Does Extreme Modeling pick up from where Agile Modeling leaves off?

Report this post to a moderator | IP: Logged

Old Post 12-20-2002 02:59 AM
SZ is offline Click Here to See the Profile for SZ Click here to Send SZ a Private Message Visit SZ's homepage! Find more posts by SZ Add SZ to your buddy list Edit/Delete Message Reply w/Quote
Scott Ambler
Senior Member

Registered: Dec 2002
Location: Just North of Toronto, Canada
Posts: 31

MDA

The things that Marko talks about falls under the umbrella of AM, and I use Poseiden and often recommend it to people. However, there is far more to AM than the CASE-oriented vision of XM.

The MDA vision is very interesting, and I have no doubt that some people will follow it, but I don't think that it's for the majority of developers. The MDA vision is almost identical to the I-CASE vision of the 1980s CASE tool vendors. It sounded great in theory, and there were some tools that arguably fulfilled it, but it still failed in practice. The fundamental reasons why I believe the MDA is a loser:
1. The vast majority of developers do not have sufficiently sophisticated modeling skills, nor do they seem predisposed to gain them, to use the types of tools that the MDA vision will result in. Right away this puts this vision into a niche category.
2. Although the vendors talk a good marketing game, I just don't see them in practice supporting the level of integration required to make MDA work. XMI is challenged because each tool won't fully support it and will extend it in different directions.
3. Because the MDA and XMI rely on the UML, and because the UML is not complete (no UI or data models for instance) this will further motivate tool vendors to go in different directions.

The MDA is a great vision, it's just far too ahead of its time. For what it's worth a couple of years ago Ivar Jacobson gave a speech at UML World describing the MDA vision. His prediction was that in 20 years all development would be modeling driven that the vast majority of developers wouldn't write code anymore. This was equivalent to the shift from 2GLs (assembler) to 3GLs (COBOL). He also described several other visions that he had in the past -- adoption of objects, use cases, and a few others -- arguing that his power of prediction was pretty good. The interesting thing is that for each of his other predictions he consistently mis-judged the time frame by 7x. Assuming he's done the same again, it'll be 140 years until the MDA vision is achieved.

The bottom line is that I will be incredibly surprised to see the MDA vision reached in my lifetime, and I fully expect to live for another 50 or 60 years. In an environment where we're lucky to get developers to sketch a diagram on a whiteboard, do you really think it's reasonable for them to start using sophisticated modeling tools?

- Scott

__________________
Scott W. Ambler

Report this post to a moderator | IP: Logged

Old Post 12-20-2002 11:43 AM
Scott Ambler is offline Click Here to See the Profile for Scott Ambler Click here to Send Scott Ambler a Private Message Visit Scott Ambler's homepage! Find more posts by Scott Ambler Add Scott Ambler to your buddy list Edit/Delete Message Reply w/Quote
All times are GMT. The time now is 12:39 AM. Post New Thread    Post A Reply
  Last Thread   Next Thread
Show Printable Version | Email this Page | Subscribe to this Thread

Forum Jump:
Rate This Thread:

Forum Rules:
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is OFF
vB code is ON
Smilies are ON
[IMG] code is OFF
 

< Contact Us - Objects by Design >

Powered by: vBulletin Version 2.3.5
Copyright ©2000 - 2017, Jelsoft Enterprises Limited.
Copyright ©1999-2005, Objects by Design, Inc.