code: public static boolean isUrl(String resourceLocation) {
          if (resourceLocation == null) {
              return false;
          }
          if (resourceLocation.startsWith(CLASSPATH_URL_PREFIX)) {
              return true;
          }
          try {
              new URL(resourceLocation);
              return true;
          } catch (MalformedURLException ex) {
              return false;
          }
      }
docs: Return whether the given resource location is a URL:
  either a special "classpath" pseudo URL or a standard URL.
  
  @param resourceLocation the location String to check
  @return whether the location qualifies as a URL
  @see #CLASSPATH_URL_PREFIX
  @see java.net.URL