Working With Model Items and Diagrams > Working with diagrams > Diagram types > Class diagram
Class diagram
For information about Class Modeling in Modeler, see Overview of class modeling.
A Class Diagram shows a view of all or part of your Class Model. You can have many Class Diagrams in a model.
You can create a Class Diagram through the context menu of a Package: right-click the Package, and select New > UML > Structure > Class Diagram.
Alternatively, if you have configured to include New Diagram in the Quick Access Toolbar, you can select New Diagram > Class Diagram.
You must create the following item types through the Class Diagram:
Association
Generalization
IO Flow
Ternary Association
The following sections provide information about how a Class Diagram is used in the model. For more information about an item, property or model part, click it.
Shows these dictionary items
Like most diagrams, a Class Diagram can show variability items and relationships. See Overview of variability items and relationships on diagrams.
For most diagram symbols, you can change the presentation of the symbol through the Style view options (See Style view options - all diagrams.), and change the showing of Stereotypes and Tag Definitions through the Stereotypes view options ( Stereotypes view options for a symbol - all diagrams). When a symbol has additional view options for changing its presentation, this icon is shown - to see how the view options can change the presentation, click the icon.
Activity
Actor
Actual Template Parameter
Association
Attribute
Basic Type
Call Behavior Action (as a composite aggregation symbol)
Central Buffer (as an association symbol)
Class
Comment
Constraint
Data Store (as an association symbol)
Data Type
Dependency
Formal Template Parameter
Generalization
IO Flow
Interface
Input Pin (as an association symbol)
Operation
Output Pin (as an association symbol)
Package
Qualifier
Reception
Role
Signal
Ternary Association
Ternary Role
Type Definition
Use Case
* 
The Return Type and Parameters of an Operation can be set through the Operation Signature displayed on the Class Diagram. The Type and Default value of an Attribute can be set through the Attribute Signature. For more information, see Using a parameter signature to specify properties, Using an attribute signature to specify properties, Using an event signature to specify name and parameters and Using an operation signature to specify properties and parameters.
These items (which are not documented in the reference topics) can also appear on a Class Diagram:
• Association Class Link - links a Class, Data Type, Interface or Signal to an Association or Ternary Association. The linked Class, Data Type, Interface or Signal can then be used as an association Class.
• Frame Box - provides a way of adding a box or background image to the diagram.
• Note - provides a way of adding text to the diagram.
• Note Link - links a Constraint, Comment or Note to an item on the diagram.
• Nesting Link - shows item ownership of another item. For more information about working with nested Classes, Data Types, Interfaces or Signals, see Overview of nested classes (includes data types, interfaces, and signals)
Properties
A Class Diagram has these properties:
• Name
• Type
Owned by
Model
Package
Used in these parts of the model
Class Model
Can be linked to these dictionary items
Stereotype
*