Multiple model approach versus Rose controlled units

Two key differences between Rational Rose® and the new UML modeling products involve models and model management. While you can create and open multiple models simultaneously in Software Architect, Software Modeler, Systems Developer you can only open one model at a time in Rose. Further, in the new UML modeling products, you can only control models at the model level; you do not use the controlled unit concept to refine and break up a model in multiple levels and sections.

You can have multiple projects and models open at the same time in the new UML modeling products. You can use this multi-model capability to work at different levels of abstraction, while still maintaining traceability across models. The multi-model approach is a key paradigm shift because you can only open one Rose model at a time, which is sometimes cumbersome when you need to work and modify several related models in unison. Now you can open multiple models simultaneously and tie them together at various levels of your model hierarchy through shortcuts, relationships, and cross-references between models.

Before you learn more about the model management capabilities in the new UML modeling products, it is important to review how controlled units work within Rose.

Controlled units in Rose

In order to share parts of a Rose model with multiple users, or to simply reduce the size of a single model, you can break up a model into individual chunks, commonly referred to as controlled units. Controlled units help you manage a model by dividing it up and breaking it into smaller, more manageable sections. It is very common for software development teams to work in parallel by sharing out and placing controlled units in a configuration management system such as IBM® Rational® ClearCase®.

For example, when you create a controlled unit from a package, its contents are moved from the model file and stored in the new file. The new file contains the following information:

The original file no longer holds the contents of the package. Instead, the original model file only references the new controlled unit’s file.
Note: A model workspace is a snapshot of all currently loaded units and open diagrams. When you load the workspace, Rose restores the snapshot by loading the specified controlled units and opening the correct diagrams. Rose model workspace files are not imported because the new UML modeling products do not support controlled units.

Model management in the new UML modeling products

The model management approach in the new UML modeling products is a major change from Rose. In the new UML modeling products, you manage and control your models at the model level only; the concept of controlled units is not carried over from Rose. While the new UML modeling products do not use controlled units, it does not mean that the information stored in controlled units is lost upon import. When you import a Rose model, all controlled unit content is automatically copied into the imported model. The controlled unit no longer resides as a separate file and is incorporated into a standard, monolithic UML 2.0 model.

Once you import your Rose model, you can break up your model into separate physical models. For example, if your Rose model contains several subsystem packages that you had defined as controlled units, you may decide to make a separate model out of each subsystem. Creating models from each subsystem gives you the same control that you had when the subsystems were controlled units in Rose.

The new UML modeling products contain several capabilities that help you break up, divide, and manage your imported models. Once you import your model, you can:

While the model management capability between each tool is different, you can still achieve the same results; you can divide up your model at the model level instead of using the controlled unit concept.

Related concepts
Model-driven development
UML modeling and visual editing
Transformations
Rose top-level model views
Model property sets and UML 2.0 profiles
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