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copied!<blockquote> <p><strong>what do they mean by family of dependent or related objects</strong></p> </blockquote> <p>Using an example from <a href="http://rads.stackoverflow.com/amzn/click/0201633612" rel="nofollow">Design Patterns</a> by the Gang of Four:</p> <ul> <li><strong>AbstractFactory</strong> (<code>WidgetFactory</code>)</li> <li><strong>ConcreteFactory</strong> (<code>MotifWidgetFactory</code>, <code>PMWidgetFactory</code>)</li> <li><strong>AbstractProduct</strong> (<code>Window</code>, <code>ScrollBar</code>)</li> <li><strong>ConcreteProduct</strong> (<code>MotifWindow</code>, <code>MotifScrollBar</code>, <code>PMWindow</code>, <code>PMScrollBar</code>)</li> </ul> <p><code>public abstract class WidgetFactory {...}</code></p> <p><code>public class MotifWidgetFactory extends WidgetFactory {...}</code></p> <p><code>public class PMWidgetFactory extends WidgetFactory {...}</code></p> <p>Let's start with the <code>MotifWidgetFactory</code>. It will produce a family of concrete products that extend or implement the abstract products. Since they are all built by the same factory, they play nice together. You cannot make a <code>PMScrollBar</code> work with a <code>MotifWindow</code>.</p> <blockquote> <p><strong>What people are doing on the name of factory pattern is below...it looks like a utility class where we are passing the class and getting the object instance.</strong></p> </blockquote> <p>Your example is a factory in that it produces an object. In this case, retrieving a singleton from a <code>Map</code>. It does not follow the "Factory Method" or "Abstract Factory" patterns and is therefore only a factory in name.</p>

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