@Override
    public void write(final Kryo kryo, final Output output, final URL url) {
        kryo.writeObject(output, url.toExternalForm());
    }
Kryo serializer for {@link URL}.

@author Jerome Leleu
@since 4.0.0
support/cas-server-support-memcached-core/src/main/java/org/apereo/cas/memcached/kryo/serial/URLSerializer.java