hrows an <code>IllegalArgumentException</code>.</div>
<dl>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>name</code> - a <code>String</code> specifying the name of the header</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>a <code>long</code> value representing the date specified in the header expressed as the number of
 milliseconds since January 1, 1970 GMT, or -1 if the named header was not included with the request</dd>
<dt><span class="throwsLabel">Throws:</span></dt>
<dd><