Hi Shailesh, my book answers this question in chapter 1 and then goes on to show the advantages at work. The short answer is that UML is like the standard alphabet, whether it be the Latin, Arabic or Greek alphabet. Lets use the Latin alphabet, A-Z, as an example: put two groups with this alphabet in two different places, and ask them to write a book (to communicate high level "thinks"). The first thing they'll have to do is define a language - the nouns, verbs, vocabulary etc. Now, since they are in different places, they will naturally not arrive at the same language. For instance, one will define Italian, and the other will define English. Thus, even though they both did a great job, they still can't talk to each other. This is what happens with UML alone. By defining a modeling style and an architectural style, we are adding the grammar and common language aspects to UML to allow teams in differnt places to create masterpieces (designs and systems) that are not only compatible, but at a much higher level than the alphabet alone. James Joyce and Earnest Hemingway, after all, created masterpieces based on the English language (which used the alphabet) that we could all read -- i.e. reuse and deploy in IT terms. I hope this short analogy helped... much more in the book, of course :-) Richard
Richard G. Hubert <br /><a href="http://www.iO-Software.com" target="_blank" rel="nofollow">Interactive Objects Software GmbH</a><br />Author of <a href="http://www.amazon.com/exec/obidos/ASIN/0471105600/ref=ase_electricporkchop" target="_blank" rel="nofollow">Convergent Architecture: Building Model-Driven J2EE Systems with UML (OMG Press)</a>
Joined: Oct 12, 2000
thanks , Robert. you have put the things in the perspective. Definitely it helped. but , one thing I would like to mention , UML was created to reduce the communication head . By looking at the symbols , the developer should know what to do. Same happens with Design patterns. it created common vocabulary between designer & programmer. so , once again adding vocabulary to diagrams ? Am I making any mistake in understanding you ? Shailesh. [ March 07, 2002: Message edited by: shailesh sonavadekar ]
Richard G. Hubert
Joined: Jan 10, 2002
Hi shailesh, back on the ranch. To answer your question: UML is great progress. It helps us share a common alphabet and will evolve to add higher levels of expression over time. In fact the OMG initiative on Model Driven Architecture that I cover in the book is a step in this direction. Many, not all, of the MDA standards will influence or move into UML standard over time. That's why it is extremly important that the UML and MDA be in the hands of a well operated, open standardization organization such as the OMG who will assure proper evolution and coordination of both initiatives. So, UML + MDA ist the winning approach: UML is the basic alphabed with symbols and a basic lexicon, MDA adds modeling styles and other aspects which are the higher levels of exprecssion comparable to grammars and usage styles (e.g. The Chicago Language of Style) in human/natural languages (e.g. English). Hope that helps.
subject: how model driven architecture or modelling different than UML ?