Spring Async DeferredResult在Tomcat 8中不起作用

问题内容：

我使用Spring 4.0.5和Servlet API 3.1.0创建了一个异步MVC应用程序。异步行为在使用Firefox 24的Jetty
8.0中运行良好，但是我无法使其在Tomcat 8.0和Firefox
24中正常工作。我正在使用DeferredResult管理异步请求。知道我缺少什么吗？这可能是某些Tomcat设置或web.xml中的某些内容，因为完全相同的Java代码在Jetty中可以很好地工作。

当异步请求最终产生结果并且应该写入响应时，我看到记录了以下消息：

WebAsyncManager - Dispatching request to resume processing
RequestResponseBodyMethodProcessor - Written [true] as "application/json" using MappingJacksonHttpMessageConvertor
DispatcherServlet - Null ModelAndView returned to DispatcherServlet with name 'app': assuming HandlerAdapter completed request handling
DispatcherServlet - Successfully completed request

长时间运行的请求永远不会回到我的浏览器，最终我在Tomcat日志中看到此超时错误：

CoyoteAdapter.asyncDispatch Exception while processing an asynchronous
request
java.lang.IllegalStateException: Calling [asyncTimeout()] is not valid
for a request with Async state [Dispatching]

--server.xml–

    <Connector port="8080" protocol="org.apache.coyote.http11.Http11NioProtocol" 
        maxConnections="100"
               maxThreads="100"
               connectionTimeout="150000" 
               asyncTimeout="150000" />

--Tomcat web.xml–

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
                      http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
  version="3.1">

    <servlet>
        <servlet-name>default</servlet-name>
        <servlet-class>org.apache.catalina.servlets.DefaultServlet</servlet-class>
        <init-param>
            <param-name>debug</param-name>
            <param-value>0</param-value>
        </init-param>
        <init-param>
            <param-name>listings</param-name>
            <param-value>false</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
        <async-supported>true</async-supported>
    </servlet>

    <servlet>
        <servlet-name>jsp</servlet-name>
        <servlet-class>org.apache.jasper.servlet.JspServlet</servlet-class>
        <init-param>
            <param-name>fork</param-name>
            <param-value>false</param-value>
        </init-param>
        <init-param>
            <param-name>xpoweredBy</param-name>
            <param-value>false</param-value>
        </init-param>
        <load-on-startup>3</load-on-startup>
        <async-supported>true</async-supported>
    </servlet>


    <!-- The mapping for the default servlet -->
    <servlet-mapping>
        <servlet-name>default</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

    <!-- The mappings for the JSP servlet -->
    <servlet-mapping>
        <servlet-name>jsp</servlet-name>
        <url-pattern>*.jsp</url-pattern>
        <url-pattern>*.jspx</url-pattern>
    </servlet-mapping>    
</web-app>

-Spring web-app web.xml–

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
                      http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
  version="3.1">

    <!-- Creates the Spring Container shared by all Servlets and Filters -->
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <context-param>
        <param-name>webAppRootKey</param-name>
        <param-value>my-async-app</param-value>
    </context-param>

    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:spring/app-config.xml</param-value>
    </context-param>

    <!-- Handles all requests into the application -->
    <servlet>
        <servlet-name>app</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:spring/controllers-config.xml</param-value> 
        </init-param>
        <load-on-startup>1</load-on-startup>
        <async-supported>true</async-supported>
    </servlet>

    <!-- Maps all /app requests to the DispatcherServlet for handling -->
    <servlet-mapping>
        <servlet-name>app</servlet-name>
        <url-pattern>/app/*</url-pattern>
    </servlet-mapping>
</web-app>

问题答案：

描述的是关系到Tomcat的一个bug这个问题在这里，这里和这里。

可能的解决方案：

使用更稳定的Tomcat版本，例如Tomcat 7.0.47，该错误已得到修复。
使用更高级的调度程序，例如org.springframework.web.servlet.DispatcherServlet

按照此处的建议覆盖HttpServlet ：

public class AsyncServlet extends HttpServlet {

protected void doGet(final HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {

    if (request.isAsyncStarted()) {
        response.getWriter().write("asyncResult=" + request.getAttribute("asyncResult"));
    } else {
        final AsyncContext asyncContext = request.startAsync(request, response);

        asyncContext.addListener(new AsyncListener() {
            public void onTimeout(AsyncEvent event) throws IOException {
                request.setAttribute("asyncResult", "timeout\n");
                asyncContext.dispatch();
            }

            public void onStartAsync(AsyncEvent event) throws IOException {
            }

            public void onError(AsyncEvent event) throws IOException {
            }

            public void onComplete(AsyncEvent event) throws IOException {
            }
        });

        asyncContext.setTimeout(5000L);
    }
}

}

Spring Async DeferredResult在Tomcat 8中不起作用

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