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51 lines
955 B
ReStructuredText
51 lines
955 B
ReStructuredText
`Singleton`_
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============
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**THIS IS CONSIDERED TO BE AN ANTI-PATTERN! FOR BETTER TESTABILITY AND
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MAINTAINABILITY USE DEPENDENCY INJECTION!**
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Purpose
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-------
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To have only one instance of this object in the application that will
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handle all calls.
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Examples
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--------
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- DB Connector
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- Logger (may also be a Multiton if there are many log files for
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several purposes)
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- Lock file for the application (there is only one in the filesystem
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...)
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UML Diagram
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-----------
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.. image:: uml/uml.png
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:alt: Alt Singleton UML Diagram
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:align: center
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Code
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----
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You can also find these code on `GitHub`_
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Singleton.php
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.. literalinclude:: Singleton.php
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:language: php
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:linenos:
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Test
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----
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Tests/SingletonTest.php
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.. literalinclude:: Tests/SingletonTest.php
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:language: php
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:linenos:
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.. _`GitHub`: https://github.com/domnikl/DesignPatternsPHP/tree/master/Creational/Singleton
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.. _`Singleton`: http://en.wikipedia.org/wiki/Singleton_pattern
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