in src/main/java/org/apache/sling/security/impl/ReferrerFilter.java [223:230]
private void add(final List<URL> urls, final String ref) {
try {
final URL u = new URL(ref);
urls.add(u);
} catch (final MalformedURLException mue) {
logger.warn("Unable to create URL from {} : {}", ref, mue.getMessage());
}
}