private String makeAbsolute(String url, String link) {
    if (link.matches("http://.*")) {
      return link;
    }
    if (link.matches("/.*") && url.matches(".*$[^/]")) {
      return url + "/" + link;
    }
    if (link.matches("[^/].*") && url.matches(".*[^/]")) {
      return url + "/" + link;
    }
    if (link.matches("/.*") && url.matches(".*[/]")) {
      return url + link;
    }
    if (link.matches("/.*") && url.matches(".*[^/]")) {
      return url + link;
    }
    throw new RuntimeException("Cannot make the link absolute. Url: " + url
        + " Link " + link);
  }