Do you have to add unimplemented methods?
<p>I am trying to add a listener to a <code>JFrame</code> closing operation:</p>

<pre><code>addWindowListener(new WindowListener() {
    @Override
    public void windowClosing(WindowEvent e) {
        setVisible(false);
    }
});
</code></pre>

<p>The thing is that Eclipse keeps telling me I have to "add unimplemented methods", which I assume it gets from the <code>WindowListener</code>. I am confused, though, as to why you need to implement all these other methods as well, if you only need to override one? And if I do add all those other methods, but don't put any content in them e.g.</p>

<pre><code>@Override
public void windowActivated(WindowEvent e) {}
</code></pre>

<p>will the default behaviour for this method get lost? Or will it only get overriden if I write something inside the method?</p>