Netbeans -> not recognising methods from classes in the Libraries
<p>I'm using Netbeans 8.1 I'm trying find if an array is empty using the <code>isEmpty()</code> method in the <code>ArrayList</code> class. 
However, when I try to call it it gives me the "cannot find symbol" hint.
I have imported <code>java.util.ArrayList</code> and that gives me the "Unused Import" hint.</p>

<p>I've tried it with <code>size()</code> and <code>add()</code> as well, which are both methods from <code>ArrayList</code>, to the same success.</p>

<p>It's not misspelled, and <code>java.util.ArrayList</code> is definitely in the libraries.</p>

<p>I've also tried </p>

<ul>
<li><p>deleting the cache,</p></li>
<li><p>clean and build and</p></li>
<li><p>copying everything to a new project</p></li>
</ul>

<p>if that makes any difference.</p>