Message based modeling

Looking for input about message based modeling as compared to responsibility based modeling, per D. Taylor's Object Technology: A Managers Guide.
Thanks
BJKerser

Brian,
Thanks for the reply. You are right, there is no "message based modeling". As you can tell, I am still trying to figure out how all this works. We are using CFObjects for Cold Fusion and trying to build an HR Portal that supports Payroll, Benefits, HR and other departments. This means (we think) that the attributes for an employee for a Benefits user are a lot diffrent than the attributes for a Payroll user, but we really like the idea that either of these would be able to udate the employee phone number, for example. Thanks again for the reply.
BJKersey

In reeference to previous post. It's often suggested that emplyee be derived from person but since being an employee is a persons relationship with a company it can often be more appropriate to model this with a relationship class. Ie.
RElationship
|
Employee (person*, company* and other employee attribs)

Originally posted by bjkersey: Looking for input about message based modeling as compared to responsibility based modeling, per D. Taylor's Object Technology: A Managers Guide. Thanks BJKerser

This is an interesting and very open-ended question. I hope my rely is of some use. I have not read this book since 1998 and do not have a copy but I believe he defined OO as
1. Polymorphism (here is where he referred to messages)
2. Inheritance
3. Encapsulation.

In his book the role of the "Message" was discussed at length. I do not recall any discussion of modelling techniques - I could be mistaken. I think the term "Message" was originally defined by SIMULA - once again I could be mistaken.
Anyway - when a class is modelled typically attributes(properties), methods and relationships will be captured. Many time the scope/visibility of each of the above is also captured. I believe that messages could arguably be considered the public interface of a class.
I hope this serves to start a discussion and or a request for clarification or elaboration.

Brian Leonard

Originally posted by bjkersey: Brian, Thanks for the reply. You are right, there is no "message based modeling". As you can tell, I am still trying to figure out how all this works. We are using CFObjects for Cold Fusion and trying to build an HR Portal that supports Payroll, Benefits, HR and other departments. This means (we think) that the attributes for an employee for a Benefits user are a lot diffrent than the attributes for a Payroll user, but we really like the idea that either of these would be able to udate the employee phone number, for example. Thanks again for the reply. BJKersey

Without doing some ColdFusion research I cannot give you implementation level information - but the concepts you are considering are exactly the power of OOA and D.
The problem you described is commonly solved using a class hierarchy and inheritance. At the top of the hierarchy you define a base class (i.e person) that has the common or generalized atributes of all member classes (i.e. name, email, phone etc.)
Then specialization or descendant classes would be defined that have the attributes that are specific or meaningfull to the class being described (i.e. Customer might have a credit card number while and Employee would have a hire date - since both classes extend Person they also both have the name, email and phone attributes defined in Person.)
The problems you are dealing with are not unique and ther have been significant efforts defing a set of business related classes.
I suggest looking here
Old UBB Archived Link: [URL=http://www4.ibm.com/software/ad/sanfrancisco/.]http://www4.ibm.com/software/ad/sanfrancisco/.[/URL]

This is one example of a set of business objects implemented in this case using JAVA.
Of course you can develop your own - I have many many times and each time I did a better job.
Now I spend more time researching others efforts, applying design patterns to solve problems and adopting or extending the applicable efforts of others to design each process automation solution.
Let me know if I can be of any more help.
Brian Leonard
Do you know UML? Do you have any modelling tools - I could send an example model of a class hierarchy if you like.