用Freemarker渲染一个字符串模板

StringTemplateRenderer.java

protected String renderResponse(Map ctx, String stringTemplate) {
        Configuration cfg = new Configuration();
        StringTemplateLoader stringLoader = new StringTemplateLoader();
        stringLoader.putTemplate("updateResponseTemplate", stringTemplate);
        cfg.setTemplateLoader(stringLoader);
        Writer out = new StringWriter(2048);
        
        try {
            Template tpl = cfg.getTemplate("updateResponseTemplate","utf-8");
            tpl.process(ctx, out);
        } catch (IOException e) {
            logger.error("Get update response template occurs error.",e);
        } catch (TemplateException e) {
            logger.error("Process template occurs error.template content is:\n {}", e, stringTemplate);
            throw new IllegalArgumentException("Error update response template.",e);
        }
        
        return out.toString();
}