Building an Auto-Decomposition Diagram

Technote (FAQ)


Building an Auto-Decomposition Diagram


In the course of a project, you will often find it useful to create Parent-Child relationships between diagrams -- graphically modeling the detailed logic of a single symbol on a 'parent' diagram with one or more 'child' diagram of various types. This hides complexity at the parent level, and makes the diagrams easier to comprehend.  At certain points in the project, you will want to be able to view the hierarchy of the diagrams you have created.  System Architect 2001 allows you to do this through an Auto-Decomposition diagram.

When you build an Auto-Decomposition diagram, you choose the diagrams whose interrelationships you want to view and System Architect automatically creates a model of the information in those diagrams. The form this model takes depends on the option you choose:

  • Functional Decomposition ,
  • Diagram Hierarchy , or
  • Diagram Explosion .

In this week's tip we'll take a look at the Diagram Hierarchy . The Diagram Hierarchy auto-decomposition shows a hierarchy of diagrams and their symbols, and their child diagrams and their symbols, etc.  It depicts all symbols on all diagrams, in a  descending structure from the original chosen Top diagram.

Let's take a look at an example...

In this example, we will examine a hierarchy of parent-child links that detail Making a Reservation in a Hotel Reservation System. We will look at diagrams in System Architect's Samples project encyclopedia.  We will begin with a Business Concept diagram for the Hotel, and work down through greater levels of detail, through a UML Use Case context diagram for the system, and then a UML Activity diagram and a UML Sequence diagram for making a reservation.

For this example, we will first set up the following parent-child links:

On a high-level Business Concept Diagram for the International Hotel Reservation , we represent the hotel's Reservation System with a graphical symbol. To show the details of this system, we attach a child Use Case diagram called Hotel Reservations -- Overview to the symbol.

1. Open the Business Concept Diagram called International Hotel Reservation .

2. Select the Make Reservations symbol. Right click on it and select Child Attach . The Select for Attaching dialog appears.

3. From the Type drop down list choose UML Use Case . A list of the UML Use Case diagrams in the encyclopedia appears underneath.

4. Select Hotel Reservations -- Overview and click Attach . Select OK to save changes to the diagram.

Using the same procedure detailed above, attach the following diagrams as 'children' to the following 'parent' symbols:

  • In the Hotel Reservations -- Overview Use Case diagram, attach, to the Make Provisional Reservation Use Case symbol, the UML Activity diagram Make Provisional Reservation.
  • In the Hotel Reservations -- Overview Use Case diagram, attach, to the Make Provisional Reservation Use Case symbol, the UML Sequence diagram Make Provisional Reservation.

Now let's get a bird's-eye view of these parent-child links by having System Architect automatically create a Decomposition diagram. 

To create the Auto-Decomposition diagram:

1. From the File menu, select New Diagram .  Choose Auto-Decomposition as the type and name it Reservations .

2. From the Draw menu, select Decomposition , Diagram Hierarchy .  The Select for Automatic Decomposition dialog appears.

3. In the Type drop-down list box, select Business Concept to reveal the Business Concept diagram in this encyclopedia. Select International Hotel Reservation   and click Build .

System Architect will create a hierarchy of all the symbols in the diagrams you selected. See the example below which shows part of the autodecomposition diagram -- a part that shows relationships among the symbols in the UML Use Case, UML Activity, and UML Sequence diagrams that you linked.

If you look at the Decomposition diagram, you will notice that Diagrams are represented by symbols of a certain color (green in the example below), and symbols that appear on the diagrams are a different color (brown in the example below) -- you can of course change these colors before or after automatically building the diagram.

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More support for:

Rational System Architect
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Software version:

11.0, 11.1, 11.2

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