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copied!<p>Yes, so basically making an object that encapsulates the behavior and other information that is needed when an action takes place can be seen as using the <a href="http://en.wikipedia.org/wiki/Command_pattern" rel="nofollow noreferrer">command pattern</a>.</p> <p>The Wikipedia article linked above uses the <a href="http://java.sun.com/javase/6/docs/api/javax/swing/Action.html" rel="nofollow noreferrer"><code>Action</code></a> interface as an example of the command pattern in Swing. The <code>Action</code> interface is a subinterface of <a href="http://java.sun.com/javase/6/docs/api/java/awt/event/ActionListener.html" rel="nofollow noreferrer"><code>ActionListener</code></a>, so a class that implements <code>Action</code> will have to implement the <code>actionPerformed</code> method.</p> <p>Therefore, a class implementing <code>Action</code> will be encapsulating some operations which will be performed when an action occurs. And that class itself can be seen to follow the command pattern.</p> <p>When it comes to the implementation, in general, an <a href="http://java.sun.com/javase/6/docs/api/javax/swing/AbstractAction.html" rel="nofollow noreferrer"><code>AbstractAction</code></a> can be easier to use than implementing <code>Action</code> as it has several methods that needs to be overridden. An example using <code>AbstractAction</code> can be:</p> <pre><code>class MySpecialAction extends AbstractAction { @Override public void actionPerformed(ActionEvent e) { // Perform operations. } } </code></pre> <p>The <code>MySpecialAction</code> is a command pattern object -- it has the behavior it must exhibit when an action takes place. When instantiating the above class, one could try the following:</p> <pre><code>MySpecialAction action = new MySpecialAction("Special Action", mySpecialIcon); </code></pre> <p>Then, the action can be registered to multiple components, such as <code>JButton</code>s, <code>JMenuItem</code>s and such. In each case, the same <code>MySpecialAction</code> object will be called:</p> <pre><code>JMenuItem specialMenuItem = new JMenuItem(action); /* ... */ JButton b = new JButton(action); </code></pre> <p>In both cases, the action that is associated with each component, the button and the menu item, refer to the same <code>MySpecialAction</code> action object, or command. As we can see, the <code>MySpecialAction</code> object is functioning as a object following the command pattern, as it encapsulates some action to be performed at a the time when an action takes place.</p>

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