why some IOException is thrown out from library code?
<p>I am using a third party library code, calling just one method. The method is declared to throw ZZException, however when running in the real environment, we found this method throwed out IOExceoption sometime.</p>

<pre><code>public void TestMethod() throws ZZException
</code></pre>

<p>I am wondering why there is no decalrtion for IOException thrown? If not declaring throw IOException, can IOException being throwed out?</p>

<p>BTW, ZZException is  subclass of RuntimeException</p>
