在 Thymeleaf 方言处理器中访问 HttpServletRequest 和 HttpServletResponse

我正在尝试创建一个执行 ServletDispatcher.include 的 Thymeleaf 方言处理器。我扩展了 AbstractElementTagProcessor 并重写了 doProcess 方法。相关代码片段是：

@Override
protected void doProcess(final ITemplateContext context, final IProcessableElementTag tag, final IElementTagStructureHandler structureHandler) {
    ServletContext servletContext = null; // TODO: get servlet context
    HttpServletRequest request = null; // TODO: get request
    HttpServletResponse response = null; // TODO: get response

    // Retrieve dispatcher to component JSP view
    RequestDispatcher dispatcher = servletContext.getRequestDispatcher("/something");

    // Create wrapper (acts as response, but stores output in a CharArrayWriter)
    CharResponseWrapper wrapper = new CharResponseWrapper(response);

    // Run the include
    dispatcher.include(request, wrapper);

    String result = wrapper.toString();

    // Create a model with the returned string
    final IModelFactory modelFactory = context.getModelFactory();
    final IModel model = modelFactory.parse(context.getTemplateData(), result);

    // Instruct the engine to replace this entire element with the specified model
    structureHandler.replaceWith(model, false);

我过去以自定义 JSP 标记的形式编写了类似的代码。问题是：我不知道如何访问 ServletContext、HttpServletRequest 和 HttpServletResponse！ 这是否可以完成，或者我应该接受 Thymeleaf 太擅长隐藏 HTTP 上下文了？

您可以访问请求（通过使用#request使您可以直接访问的对象javax.servlet.http.HttpServletRequest对象）参数和会话（与#session使您可以直接访问的对象javax.servlet.http.HttpSession对象）属性直接在 Thymeleaf 视图中：

${#request.getAttribute('foo')}
${#request.getParameter('foo')}
${#request.getContextPath()}
${#request.getRequestName()}

<p th:if="${#request.getParameter('yourParameter') != null
      th:text="${#request.getParameter('yourParameter')}"}">Request Param</p>

${#session.getAttribute('foo')}
${#session.id}
${#session.lastAccessedTime}

<p th:if="${session != null}"> th:text="${session.yourAttribute}"</p>

阅读更多here http://www.thymeleaf.org/doc/tutorials/3.0/usingthymeleaf.html#expression-basic-objects.