Generate a Textual Description of Messages

You are going to generate a textual description of the messages existing in the communication diagram. The description should provide for each diagram in the model, the name of the message sender, the name of the message and the name of the receiver.

You generate this description using templates and generated files, because by default PowerDesigner does not provide such a feature. Templates and generated files use the PowerDesigner Generation Template Language (GTL). Generated files evaluate templates defined on metaclasses and output the evaluation result in files.

For more information on GTL, see Customizing Generation with GTL.

What Template to Define and Where?

To generate a textual description of the communication diagram message, you have to define templates on the following metaclasses:

Message: this metaclass contains details about the message sequence number and the message name, sender and receiver, this is why you define a template to evaluate the message sequence number and description in this metaclass
CommunicationDiagram: you define in this metaclass the templates that will sort the messages in the diagram and gather all message descriptions from the current diagram

For more information on the PowerDesigner metaclasses, see Resource Files and the Public Metamodel.

The generated file is defined on metaclass BasePackage in order to scan the entire model, that is to say the model itself and the packages it may contain. This is to make sure that all messages in the model and its packages are described in the generated file. There will be one generated file since metaclass BasePackage has only one instance.

Defining a Template for Generation
A generated file uses templates defined in metaclasses. The first template you have to define is on messages. The role of this template is to evaluate the message sequence number and to provide the name of the sender, the name of the message, and the name of the receiver for each message in the diagram.
Defining the Templates for the Communication Diagram Metaclass
Once you have defined the template used to evaluate each message sequence number, you have to create a template to sort these sequence numbers (compareCbMsgSymbols), and another template to retrieve all messages from the communication diagram (description).
Defining a Generated File
You are going to define the generated file in order to list the messages of each communication diagram existing in your model. To do so, you have to define the generated file in the BasePackage metaclass. This metaclass is the common class for all packages and models, it owns objects, diagrams and other packages.
Preview the Textual Description of the Communication Diagram
Since the generated file is defined in the metaclass BasePackage, you can preview the generated text in the Preview tab of the model property sheet. This also allows you to verify that the syntax of the templates and the output correspond to what you want to generate.

Parent topic: Using Profiles: a Case Study