((something).this).something_else
<p>Can someone explain what the following expression does?</p>

<pre><code>System.out.println(((Window)this).size)
</code></pre>

<p>Let's say we have this one:</p>

<pre><code>System.out.println(this.size)
</code></pre>

<p>I understand what this expression does, but I don't understand what the <code>(Window)</code> does, so the problem is what is the meaning of the <code>(Window)</code> before the keyword <code>this</code> (let's assume that <code>Window</code> is superclass of the class that I use in this example)?</p>
