code: @Nullable
    public static URL getAsURL (@Nullable final URI aURI)
    {
      if (aURI != null)
        try
        {
          return aURI.toURL ();
        }
        catch (final MalformedURLException ex)
        {
          // fall-through
          if (GlobalDebug.isDebugMode ())
            if (LOGGER.isWarnEnabled ())
              LOGGER.warn ("Debug warn: failed to convert '" + aURI + "' to a URL!");
        }
      return null;
    }
docs: Get the passed URI as an URL. If the URI is null or cannot be converted to
  an URL <code>null</code> is returned.
  
  @param aURI
  Source URI. May be <code>null</code>.
  @return <code>null</code> if the passed URI is null or cannot be converted
  to an URL.