<p> This method or field is or uses a Map or Set of URLs. Since both the equals and hashCode
method of URL perform domain name resolution, this can result in a big performance hit.
See <a href="http://michaelscharf.blogspot.com/2006/11/javaneturlequals-and-hashcode-make.html">http://michaelscharf.blogspot.com/2006/11/javaneturlequals-and-hashcode-make.html</a> for more information.
Consider using <code>java.net.URI</code> instead.
   </p>