Rational Rose

CASE Tools

Developing complex applications is made easier by using so-called CASE, or Computer-Aided Software Engineering tools. A CASE tool often includes a class modeler tool that allows the developer to design the class structure of an application in UML notation. The collection of classes making up the application together with their relationships (aggregation, association, inheritance etc.) form the "logical view" or "logical model" of the application.

Froward and Reverse Engineering

A CASE tool often has two capabilities that are important to establish the connection between the logical view (model) and the actual implementation (code) of a program.

Forward Engineering: Given the UML model, generate the corresponding code.
Reverse Engineering: Given the code for some classes, generate the corresponding model.

In most cases the CASE tool allow a wide selection of programming languages for implementation (Java, C++, VB, C#, Pascal etc.) and sometimes notations that are different from UML (Booch, OMT etc.)

Rational Software, Inc. was a company founded by the "three amigos" (Booch, Jacobson, Rambaugh) , the creators of UML. The company's main product was Rational Rose, a CASE Tool to forward and reverse engineer UML models. It is now a division of IBM.

Rational Rose has multiple "views" or models of an application. The two most important ones are the "logical view" which is the actual class model (in UML notation), and the "physical view" that consists of "components" that contain the actual (code) implementation of the classes of in the logical view.

Rational Rose Development Environment

Example: University Model

Forward Engineering

In Rational Rose:

Create the model in Logical View
Create a new Component in Component View
Right click to Open Specifications, select Realizes
Select the classes for component, right click and select Assign
Right click for the appropriate language, e.g. ANSI C++, select Generate Code ...
The Code Generation form comes up. All classes will be specified ADD or UPDATE. Hit OK to complete.

Reverse Engineering

In Rational Rose:

Click File new for and new model, cancel out of the project selection
Select Component View - Main
Add a new Component
Right click component to select Open Specifications ...
Select language e.g. ANSI C++ and hit OK
Right click ANSI C++ - Open C++ Specifications ..
On the Files tab, hit Add Files, and click the ellipse (...) button
Select all *.h and *.cpp files and hit Open then OK
Right click component to Reverse Engineer ... and hit OK
Select Logical View, there is a new folder called C++ Reversed Engineered
Select the C++ Reversed Engineered Folder
Add classes to Logical View - it will show inheritance and aggregation

Printing a UML diagram

In Rational Rose:

Select File, Print, Layout and choose Fit to page
In Printer Properties select Landscape
Hit Print Preview to check and OK to print

Click here for a more detailed description of the Rational Rose Round-Trip Engineering process.