Presentation of the Class Diagram
A class diagram is used to represent the static structure of a system, particularly the types of objects manipulated in the system, their internal structure, and the relationships between them.
Examples of objects:
• Business objects:
• John Williams, Elizabeth Davis and Paul Smith are instances of the “person” class.
• Orders 10533 and 7322 are instances of the "order" class.
• SPD-1730 Monitor is an instance of the “item” class.
• Technical objects used for programming:
• Dlg_Order_Create, Dlg_Client_Query are instances of the window class.
• Str_Client_Name, Str_Product_Comment are instances of the "string" class.
Data modeling consists of identifying the classes representing the activity of the company, and defining the associations existing between them.
The Class Diagram: summary
A class diagram includes:
• Classes, which represent the basic concepts (client, account, product, etc.).
• Associations, which define the relationships between the different classes.
• Attributes, which describe the characteristics of classes and, in certain cases, of associations.
• Operations, which can be executed on objects of the class.
Operations are not taken into account by HOPEX Information Architecture tools (synchronization, generation etc.).The class diagram also contains multiplicity definitions.
Creating a Class Diagram
A class diagram is created from a package.
To create a class diagram:
Click the icon of the package concerned and select New > Class Diagram.The diagram opens in the edit window.
A class diagram can describe a package, a use case, a class, or an instance.