From david.lightstone@prodigy.net Mon Oct 25 12:52:23 2004 Date: Sat, 25 Sep 2004 11:56:58 -0400 From: David Lightstone Reply-To: re-online@it.uts.edu.au To: RE-online@it.uts.edu.au Subject: Re: [re-online] Does OOA Have A Real Functional Modeling Technique? > Am I missing something? Is there a true (i.e., rigorous) functional modeling technique for OOA? One of the concepts in Structured Analysis that I find applicable is - Leveling (in modern jargon refactoring?). A strategy for cleaning up data flow diagrams. You basically move data stores and transformations around. The intent being to obtain a nice clean collection of DFDs (not to many transformations present on each diagram.) that is a hierarchal decomposition of the problem Years ago I found a nice drawing in a book written by Keith Edwards and titled Real-Time Structured Methods Systems Analysis. It allowed me to discover a strategy that allows me to transform Data flow diagrams into primitive object models. This by a process similar to leveling. All you have to realize is an object is a data store surrounded by data transformations. When you create the Data flow diagram: (1) use many small data stores rather than one global one; (2) Create a simple data store for each data flow (put it in the flow just to make things obvious) Once you have the DFD cleaned up, locate the stores and decide which transformations are associated with them as "methods". Declare those to be your objects Use cases dependencies can be "identified " in a similar fashion. Consider them to be data transformations. Dependencies are a consequence of the hierarchal decomposition My opinion is that Structured Analysis is a functional modeling technique for OOA. OOA as a consequence, is just a translation that allows Object Oriented Design to be facilitated ------------------------------------------------------------------------------- To send a message to this mailing list send it to re-online@it.uts.edu.au. To unsubscribe from this mailing list, email majordomo@it.uts.edu.au with the message `unsubscribe re-online' in the BODY of the mail.