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

Question

我正在尝试创建一个执行 ServletDispatcher.include 的 Thymeleaf 方言处理器。我已经扩展了 AbstractElementTagProcessor 并覆盖了 doProcess 方法。相关代码片段为:

@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);

我以前以自定义 JSP 标记的形式编写过类似的代码。问题是:我不知道如何访问 ServletContext、HttpServletRequest 和 HttpServletResponse! 这完全可以做到，还是我应该接受 Thymeleaf 太擅长隐藏 HTTP 上下文？

Answer 1

您可以访问请求(通过使用 #request 对象，使您可以直接访问 javax.servlet.http.HttpServletRequest 对象)参数和 session (使用 #session 对象，使您可以直接在 Thymeleaf View 中直接访问 javax.servlet.http.HttpSession 对象)属性:

${#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 .