puiutucutu

<?php

/**
 * Existence of Composition class requires that an external object of 
 * class B is passed in on construction
 * 
 * UML Explanation - The object at this role contains the object at the opposite role. 
 * 
 * Alternatively stated, an object of class Composition cannot be created without 
 * an object of class B (in this case through dependency injection)