ss="block">Get an existing attribute node for the attribute with the given
 name.</div>
<dl class="notes">
<dt>Parameters:</dt>
<dd><code>attributeName</code> - name of the attribute</dd>
<dt>Returns:</dt>
<dd>the attribute node</dd>
<dt>Throws:</dt>
<dd><code><a href="https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/lang/IllegalArgumentException.html" title="class or interface in java.lang" class="external-link">IllegalArgumentException</a></code> - if the attribute is not an
         attr