public String getRemoteHostname() {
        return getRequestDetails().getRemoteHostname();
    }
Returns the hostname of the client end of the connection which provided
these credentials, if known. If the hostname of the client cannot be
determined, but the address is known, the address may be returned
instead.
<p>
This is a convenience function that is equivalent to invoking
{@link RequestDetails#getRemoteHostname()} on the
{@link RequestDetails} returned by {@link #getRequestDetails()}.

@return
    The hostname or address of the client end of the connection which
    provided these credentials, or null if the hostname is not known.
guacamole-ext/src/main/java/org/apache/guacamole/net/auth/Credentials.java