Issue with making a controller method asynchronous with Spring 3.2.RC2 - spring-mvc

Question

I am trying to test the latest asynchronous feature of Spring MVC controllers but I have not been able to get it to work.
Here is the code for my async method:
#RequestMapping(value = "/hello")
public Callable<String> async(final Model model) {
System.out.println("entered async controller method");
return new Callable<String>() {
public String call() throws Exception {
Thread.sleep(2000L);
model.addAttribute("message", "asyncRequest dealt with");
System.out.println("about to return from call()");
return "hello";
}
};
}
Here is the relevant portion from web.xml:
<servlet>
<servlet-name>SpringMVC</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring/webmvc-config.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
<async-supported>true</async-supported>
</servlet>
However "about to return from call()" is never printed in the console and I never get to see such logs as this: 08:25:17 [MvcAsync1] WebAsyncManager - ...
in the console...
FYI, I use Spring 3.2.RC2

Answer 1

To further configure the async-support implement a AsyncTaskExecutor
By default Spring MVC uses a SimpleAsyncTaskExecutor to execute Callable instances returned by controller methods. For production you must replace it with an AsyncTaskExecutor implementation configured appropriately for your environment.
Create the AsyncTaskExecutor
<beans:bean id="asyncTaskExecutor" class="org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor">
<beans:property name="corePoolSize" value="5" />
<beans:property name="maxPoolSize" value="10" />
<beans:property name="queueCapacity" value="25" />
</beans:bean>
Then assign the task-executor
<mvc:annotation-driven >
<mvc:async-support default-timeout="30000" task-executor="asyncTaskExecutor" />
</mvc:annotation-driven>
http://blog.springsource.org/2012/05/10/spring-mvc-3-2-preview-making-a-controller-method-asynchronous/

Answer 2

I finally found why my sample was not working: one has to add the following to the web-mvc configuration file:
<mvc:annotation-driven>
<mvc:async-support default-timeout="3000"/>
</mvc:annotation-driven>

Answer 3

Hi doing a similar application with the following code :
public String doSlowWork() {
System.out.println("Start slow work");
try {
Thread.sleep(3000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("finish slow work");
return "index"; // return view's name
}
returning index but not giving the log info of the method