ProductsUModelUML Structure DiagramsUML Object Diagrams

A UModel® 2009 object diagram represents a single example of a class and is used to illustrate one datapoint in your application.

UML object diagrams use a notation similar to class diagrams and are used to show an instance of a class at a particular point in time. You might want to draw an object diagram to illustrate a real-life exanple of a class and its relationships.

Object diagrams can help clarify classes and inheritance and are sometimes drawn while planning classes, or to assist non-programming stakeholders who may find class diagrams too abstract.

A object can also be thought of as the description of an individual within a group, while classes describe the characteristics shared by the group. Hence “CheckingAccount” might be defined as a UML class in UModel® 2009 and “John’s checking account at Agency Bank” would be illustrated as an object diagram.

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When you create a new object, called an instance specification in the UModel toolbar and menus, you can assign an existing class to the object. UModel® 2009 automatically supplies instances of the appropriate properties from the defining class to the object, and you can then insert sample values for your object.

In the example below a new object has been created based on a class called StockTradingAccount. The modeler has not yet assigned the account balance, id, or SecretTradingPassword.

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Since object diagrams use notation very similar to class diagrams, the object diagram toolbar uses some of the same icons as the class diagram toolbar. You can use the toolbar, edit directly in the diagram, or use the properties dialog box to edit an object’s attributes and values.

The layout toolbar offers a wealth of alignment choices that become available once you select multiple elements.

Draw on UModel® 2009 to create object diagrams that illustrate instances in your own development project. Download a free 30-day trial today!