Editing Facade pattern (section)

==Structure==
=== UML class and sequence diagram ===
{{multiple image
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| footer=A sample UML class and sequence diagram for the facade design pattern
| image1=Facade Design Pattern Class Diagram UML.svg
| alt1=Facade Design Pattern Class Diagram
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| image2=Facade Design Pattern Sequence Diagram UML.svg
| alt2=Facade Design Pattern Sequence Diagram
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In this [[Unified Modeling Language|UML]] [[class diagram]], 
the <code>Client</code> class doesn't access the subsystem classes directly.
Instead, the <code>Client</code> works through a <code>Facade</code> class that implements a simple interface in terms of (by delegating to) the subsystem classes (<code>Class1</code>, <code>Class2</code>, and <code>Class3</code>).
The <code>Client</code> depends only on the simple <code>Facade</code> interface
and is independent of the complex subsystem.<ref>{{cite web|title=The Facade design pattern - Structure and Collaboration|url=http://w3sdesign.com/?gr=s05&ugr=struct|website=w3sDesign.com|access-date=2017-08-12}}</ref>

The sequence diagram 
shows the run-time interactions: The <code>Client</code> object 
works through a <code>Facade</code> object that delegates the request to
the  <code>Class1</code>, <code>Class2</code>, and <code>Class3</code>
instances that perform the request.

=== UML class diagram ===
[[File:Example of Facade design pattern in UML.png]]
; Facade
: The facade class abstracts Packages 1, 2, and 3 from the rest of the application.
; Clients
: The objects are using the facade pattern to access resources from the packages.