1C:\Documents and Settings\james\My Documents\millerjwcom\dom\gbis722online\week7\Chap18aSummary\Chap18aSummary.avi002320000001321024768385100000003619000000023200000010.0000001.00000024478651220500490Object-Oriented Design1C:\Documents and Settings\james\My Documents\millerjwcom\dom\gbis722online\week7\Chap18aSummary\Chap18aSummary.avi123200000049700000013210247683851000000232000000335400000023200000049700000010.0000001.00000024478651220500491Design Classes1C:\Documents and Settings\james\My Documents\millerjwcom\dom\gbis722online\week7\Chap18aSummary\Chap18aSummary.avi24970000001436000000132102476838510000004970000002415000000497000000143600000010.0000001.00000024478651220500492Types of Design Classes1C:\Documents and Settings\james\My Documents\millerjwcom\dom\gbis722online\week7\Chap18aSummary\Chap18aSummary.avi31436000000170400000013210247683851000000143600000021470000001436000000170400000010.0000001.00000024478651220500493Design Classes1C:\Documents and Settings\james\My Documents\millerjwcom\dom\gbis722online\week7\Chap18aSummary\Chap18aSummary.avi41704000000215900000013210247683851000000170400000016920000001704000000215900000010.0000001.00000024478651220500494Attribute and Method Visibility1C:\Documents and Settings\james\My Documents\millerjwcom\dom\gbis722online\week7\Chap18aSummary\Chap18aSummary.avi52159000000233800000013210247683851000000215900000015130000002159000000233800000010.0000001.00000024478651220500495Object Responsibilities1C:\Documents and Settings\james\My Documents\millerjwcom\dom\gbis722online\week7\Chap18aSummary\Chap18aSummary.avi62338000000249800000013210247683851000000233800000013530000002338000000249800000010.0000001.00000024478651220500496Object Responsibility1C:\Documents and Settings\james\My Documents\millerjwcom\dom\gbis722online\week7\Chap18aSummary\Chap18aSummary.avi72498000000280500000013210247683851000000249800000010460000002498000000280500000010.0000001.00000024478651220500497The Process of Object-Oriented Design1C:\Documents and Settings\james\My Documents\millerjwcom\dom\gbis722online\week7\Chap18aSummary\Chap18aSummary.avi8280500000031610000001321024768385100000028050000006900000002805000000316100000010.0000001.00000024478651220500498Refining The Use Case Model1C:\Documents and Settings\james\My Documents\millerjwcom\dom\gbis722online\week7\Chap18aSummary\Chap18aSummary.avi9316100000033210000001321024768385100000031610000005300000003161000000332100000010.0000001.00000024478651220500499Design Use Case1C:\Documents and Settings\james\My Documents\millerjwcom\dom\gbis722online\week7\Chap18aSummary\Chap18aSummary.avi10332100000036200000001321024768385100000033210000002310000003321000000362000000010.0000001.000000244786512205004910Design Use Case (continued)1C:\Documents and Settings\james\My Documents\millerjwcom\dom\gbis722online\week7\Chap18aSummary\Chap18aSummary.avi113620000000384500000013210247683851000000362000000060000003620000000384500000010.0000001.000000244786512205004911Design Use Case (continued)10Object-Oriented Design10232000000Design Classes11497000000Types of Design Classes121436000000Design Classes131704000000Attribute and Method Visibility142159000000Object Responsibilities152338000000Object Responsibility162498000000The Process of Object-Oriented Design172805000000Refining The Use Case Model183161000000Design Use Case193321000000Design Use Case (continued)1103620000000Design Use Case (continued)11132000
Teaching Notes
The approach of using object-oriented techniques for
designing a system is referred to as object-oriented design. Recall that object-oriented
development approaches are best suited to projects that will implement systems using
emerging object technologies to construct, manage, and assemble those objects into useful
computer applications. Object-oriented design is the continuation of object-oriented
analysis (Chapter 10), continuing to center the development focus around object
modeling techniques.
During object-oriented design, entity objects are refined
while other types of objects are identified that will be introduced as the result of
physical implementation decisions for the new system.
Teaching Notes
If your students have programmed in .NET or in Java or in any
other OO environment they should have noticed that the code they write always goes
into a class. This connection can help students understand the next slide.
Conversion Notes
The sixth edition identified only entity classes, interface
classes, and control classes.
Teaching Notes
Why all these kinds of classes?
Structuring the system this way makes the maintenance and enhancement of those classes
simpler and easier.
Entity classes are what we worked with in Chapter 10
during object-oriented analysis.
The .NET code on the previous
slide is an example of an interface class.
Control classes coordinate
message among the other kinds of classes to implement a use case.
The code to handle database reading/writing could be built into the entity class. But
having that functionality in a separate class keeps the entity class implementation-neutral,
which makes it more reusable. We will talk more about the value of reusability later in
the chapter.
System classes isolate the other options from the operating
system to keep them implementation-neutral and more reusable.
Teaching Notes
If your students have programmed in .NET or in Java or in any
other OO environment they should have noticed that the code they write always goes
into a class. This connection can help students understand the next slide.
No additional notes.
Teaching Notes
Object responsibility is closely related to the concept of
objects being able to send and/or respond to messages. For example, an ORDER object may
have the responsibility to display a customer’s order, but it may need to collaborate with
the CUSTOMER object to get the customer data, the PRODUCT object to get the product data,
and the ORDER LINE object to get specific order data about each product being ordered.
Thus, CUSTOMER, PRODUCT, and ORDER LINE have an obligation to provide the requested
service (provide requested data) to the ORDER object.
No additional notes.
Teaching Notes
In performing object-oriented analysis (OOA) we identified
objects and use cases based on ideal conditions and independent of any hardware or software
solution. During object-oriented design (OOD) we want to refine those objects
and use cases to reflect the actual environment of our proposed solution.
Teaching Notes
In this iteration of use case modeling, the use cases will be
refined to include details of how the actor (or user) will actually interface with the
system and how the system will respond to that stimulus to process the business event.
The manner in which the user accesses the system; via a menu, window, button, bar code
reader, printer, etc. should be explicitly described in detail. The contents of windows,
reports, and queries should also be specified within the use case. While refining use
cases is often time consuming and tedious, it is essential that they are completed.
Teaching Notes
Notice that the course of events now describes the windows which
will be displayed to the user, and the contents (i.e., field names) of the windows.
Descriptions of, error messages, special action buttons, possible cursor movements, and
other window characteristics should be included in each design use case step.
Teaching Notes
The design use case step includes references to
extension and abstract use cases. Recall that extension use cases extend the
functionality of the original use case by extracting complex or hard to understand logic into
its own use case. Abstract use cases are those that contain steps that are used by more