log.debug("Could not find resource at classpath: " + classPath);
    private String externalizeImage(String classPath, String mimeType) {        ClasspathResource res = new ClasspathResource(classPath, mimeType);        if (res.getResourceStream() == null) {            // no resource found at classPath, return old string            return "";        }        StringBuffer imageUrl = new StringBuffer("'");        imageUrl.append(extManager.externalize(res, ExternalizeManager.GLOBAL));        imageUrl.append("'");        return imageUrl.toString();    }