Singleton

Singleton

THIS IS CONSIDERED TO BE AN ANTI-PATTERN! FOR BETTER TESTABILITY AND MAINTAINABILITY USE DEPENDENCY INJECTION!

Purpose

To have only one instance of this object in the application that will handle all calls.

Examples

• DB Connector
• Logger (may also be a Multiton if there are many log files for several purposes)
• Lock file for the application (there is only one in the filesystem ...)

UML Diagram

Code

You can also find these code on GitHub

Singleton.php

.. literalinclude:: Singleton.php
   :language: php
   :linenos:

Test

Tests/SingletonTest.php

.. literalinclude:: Tests/SingletonTest.php
   :language: php
   :linenos: