Visitor
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*Element - Accepts visits. | *Element - Accepts visits. | ||
*Visitor - Accesses an element to perform operations. | *Visitor - Accesses an element to perform operations. | ||
| − | Figure 1 graphically describes these Visitor pattern | + | Figure 1 graphically describes these Visitor pattern relationships. |
[[image:Visitor.JPG|frame|centre|'''Figure 1: A [[UML]] [[Class diagram|class diagram]] representing the Visitor structure''']] | [[image:Visitor.JPG|frame|centre|'''Figure 1: A [[UML]] [[Class diagram|class diagram]] representing the Visitor structure''']] | ||
Revision as of 12:32, 30 July 2008
Introduction
The Visitor is a behavioural pattern. It allows the designer to define new operations on an object structure and its elements, without modifying the object structure itself.
Description
The Visitor describes three distinct components:
- Object Structure - Provides a visitor with access to its elements.
- Element - Accepts visits.
- Visitor - Accesses an element to perform operations.
Figure 1 graphically describes these Visitor pattern relationships.
Figure 1: A UML class diagram representing the Visitor structure
