<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
...
</web-app>

<!-- spring mvc -->
<servlet>
<servlet-name>SpringMvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>...</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
<async-supported>true</async-supported>
</servlet>

package org.springframework.samples.mvc.async;import java.util.concurrent.Callable;import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.context.request.async.WebAsyncTask;@Controller
@RequestMapping("/async/callable")
public class CallableController {@RequestMapping("/response-body")public @ResponseBody Callable<String> callable() {return new Callable<String>() {@Overridepublic String call() throws Exception {Thread.sleep(2000);return "Callable result";}};}@RequestMapping("/view")public Callable<String> callableWithView(final Model model) {return new Callable<String>() {@Overridepublic String call() throws Exception {Thread.sleep(2000);model.addAttribute("foo", "bar");model.addAttribute("fruit", "apple");return "views/html";}};}@RequestMapping("/exception")public @ResponseBody Callable<String> callableWithException(final @RequestParam(required=false, defaultValue="true") boolean handled) {return new Callable<String>() {@Overridepublic String call() throws Exception {Thread.sleep(2000);if (handled) {// see handleException method further belowthrow new IllegalStateException("Callable error");}else {throw new IllegalArgumentException("Callable error");}}};}@RequestMapping("/custom-timeout-handling")public @ResponseBody WebAsyncTask<String> callableWithCustomTimeoutHandling() {Callable<String> callable = new Callable<String>() {@Overridepublic String call() throws Exception {Thread.sleep(2000);return "Callable result";}};return new WebAsyncTask<String>(1000, callable);}@ExceptionHandler@ResponseBodypublic String handleException(IllegalStateException ex) {return "Handled exception: " + ex.getMessage();}}

@RequestMapping("/quotes")
@ResponseBody
public DeferredResult<String> quotes() {DeferredResult<String> deferredResult = new DeferredResult<String>();// Add deferredResult to a Queue or a Map...return deferredResult;
}// In some other thread...
deferredResult.setResult(data);
// Remove deferredResult from the Queue or Map

<mvc:annotation-driven>
<!--  可不设置，使用默认的超时时间 --><mvc:async-support default-timeout="3000"/>
</mvc:annotation-driven>

function deferred(){$.get('quotes.htm',function(data){console.log(data);deferred();//每次请求完成,再发一次请求,避免客户端定时刷新来获取数据
    });
}