Editing Proxy pattern (section)

==Structure==
=== UML class and sequence diagram ===
[[File:w3sDesign Proxy Design Pattern UML.jpg|frame|none|A sample UML class and sequence diagram for the Proxy design pattern. 
<ref>{{cite web|title=The Proxy design pattern - Structure and Collaboration|url=http://w3sdesign.com/?gr=s07&ugr=struct|website=w3sDesign.com|access-date=2017-08-12}}</ref>]]

In the above [[Unified Modeling Language|UML]] [[class diagram]], 
the <code>Proxy</code> class implements the <code>Subject</code> interface so that it can act as substitute for <code>Subject</code> objects. It maintains a reference (<code>realSubject</code>) 
to the substituted object (<code>RealSubject</code>) so that it can forward requests to it
(<code>realSubject.operation()</code>). 

The sequence diagram 
shows the run-time interactions: The <code>Client</code> object 
works through a <code>Proxy</code> object that
controls the access to a <code>RealSubject</code> object.
In this example, the <code>Proxy</code> forwards the request to the <code>RealSubject</code>, which performs the request.

=== Class diagram ===
[[File:proxy_pattern_diagram.svg|frame|none|Proxy in [[Unified Modeling Language|UML]]]]

[[File:Proxy pattern in LePUS3.gif|frame|none|Proxy in [[Lepus3|LePUS3]] ([https://web.archive.org/web/20180314162121/http://www.lepus.org.uk/ref/legend/legend.xml legend])]]