code: public static InputStream open(@Nonnull final URL url) {
  		Check.notNull(url, "url");
  
  		final InputStream ret;
  		try {
  			ret = url.openStream();
  		} catch (final IOException e) {
  			throw new CanNotOpenStreamException(url.toString(), e);
  		}
  		return ret;
  	}
docs: Tries to open an {@link InputStream} to the given {@link URL}.
  
  @param url
  URL which should be opened
  @return opened stream
  @throws net.sf.qualitycheck.exception.IllegalNullArgumentException
  if the given argument is {@code null}
  @throws CanNotOpenStreamException
  if no stream to the given {@code URL} can be established