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Concept

Class Diagrams are static and show an overview of a system. A system is composed of classes and the relationships among them.
The Class Diagram model describes the static structure of the symbols in the system. This model allows you to graphically represent symbol diagrams containing classes. Classes are arranged in hierarchies sharing common structure and behavior and are associated with other classes.
UML class diagrams show the classes of the system, their inter-relationships, and the operations and attributes of the classes.


Class diagrams are used to:

Omondo is now introducing a new Agile Modeling concept using both Java having live UML code synchronization and metamodel elements.
To see how to mix both Java and UML elements see topic: Drag and drop


In a class diagram different elements are available:


1.    New Packages can be created in the Class Diagram Editor :
Using the class diagram toolbar.
Using the class diagram editor's popup menu (Right click inside the class diagram editor >insert>package).
Using drag and drop from the Package Explorer to the class diagram editor.

The look and feel of the package elements can be changed depending on the selected diagram presentation style. Three different diagrams presentation styles can be applied to the Class Diagram Editor :

2.    New Classes can be created in the Class Diagram Editor :
Using the class diagram toolbar.
Using the class diagram editor's popup menu (Right click inside the class diagram editor >new>class).
Using the class diagram editor's popup menu (Right click inside the class diagram editor >insert>class).
Using drag and drop from the Package Explorer to the class diagram editor.

The look and feel of the class elements can be changed depending on the selected diagram presentation style. Three different diagrams presentation styles can be applied to the Class Diagram Editor :

3.    New Interfaces can be created in the Class Diagram Editor :
Using the class diagram toolbar.
Using the class diagram editor's popup menu (Right click inside the class diagram editor >new>Interface).
Using the class diagram editor's popup menu (Right click inside the class diagram editor >insert>class).
Using drag and drop from the Package Explorer to the class diagram editor.

The look and feel of the interface elements can be changed depending on the selected diagram presentation style. Three different diagrams presentation styles can be applied to the Class Diagram Editor :

4.    New Associations between classes and interfaces can be created in the Class Diagram Editor :
   Using the class diagram toolbar.

The creation of a association between classes and interfaces has four steps using the mouse:

  1. Select the association icon in the toolbar.
  2. Select a class or an interface (the color of the element becomes blue, that means it is selected), this is the first association end.
  3. Hold down the mouse button and drag the link from the first element to the second, this is the second association end.
  4. Release the mouse button.
The properties of the new association are defined through the preferences.





5.    New Generalizations between classes and interfaces can be created in the Class Diagram Editor :
   Using the class diagram toolbar.

The creation of a generalization between classes and interfaces has four steps using the mouse:

  1. Select the generalization icon in the toolbar.
  2. Select a class or an interface (the color of the element becomes blue, that means it is selected).
  3. Hold down the mouse button and drag the link from the first element to the second.
  4. Release the mouse button.
Depending on the nature of the selected elements, the created generalization is an inheritance or an implementation.
The properties of the new generalization are defined through the preferences.



6.  New Dependencies between any element can be created in the Class Diagram Editor :
   Using the class diagram toolbar.

The creation of an dependency between two elements has four steps using the mouse:

  1. Select the dependency icon in the toolbar.
  2. Select an element (the color of the element becomes blue, that means it is selected).
  3. Hold down the mouse button and drag the link from the first element to the second.
  4. Release the mouse button.
The properties of the new dependency are defined through the preferences.