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;
        }
    }
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
src/main/java/spark/utils/ResourceUtils.java