@HandlesTypes(value={HelloService.class})
public class MyServletContainerInitializer implements ServletContainerInitializer {/**
* 应用启动的时候，会运行onStartup方法；
*
* Set<Class<?>> arg0：感兴趣的类型的所有子类型；
* ServletContext arg1:代表当前Web应用的ServletContext；一个Web应用一个ServletContext；
*
* 1）、使用ServletContext注册Web组件（Servlet、Filter、Listener）
* 2）、使用编码的方式，在项目启动的时候给ServletContext里面添加组件；
* 必须在项目启动的时候来添加；
* 1）、ServletContainerInitializer得到的ServletContext；
* 2）、ServletContextListener得到的ServletContext；
*/
@Override
public void onStartup(Set<Class<?>> arg0, ServletContext sc) throws ServletException {
// TODO Auto-generated method stub
System.out.println("感兴趣的类型：");
for (Class<?> claz : arg0) {
System.out.println(claz);
}//注册组件 ServletRegistration
ServletRegistration.Dynamic servlet = sc.addServlet("userServlet", new UserServlet());
//配置servlet的映射信息
servlet.addMapping("/user");//注册Listener
sc.addListener(UserListener.class);//注册Filter FilterRegistration
FilterRegistration.Dynamic filter = sc.addFilter("userFilter", UserFilter.class);
//配置Filter的映射信息
filter.addMappingForUrlPatterns(EnumSet.of(DispatcherType.REQUEST), true, "/*");}}

@WebServlet(value="/async",asyncSupported=true)
public class HelloAsyncServlet extends HttpServlet {@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
System.out.println("主线程开始。。。"+Thread.currentThread()+"==>"+System.currentTimeMillis());AsyncContext startAsync = req.startAsync();startAsync.start(new Runnable() {
@Override
public void run() {
try {
System.out.println("副线程开始。。。"+Thread.currentThread()+"==>"+System.currentTimeMillis());
service();
startAsync.complete();AsyncContext asyncContext = req.getAsyncContext();
//4、获取响应
ServletResponse response = asyncContext.getResponse();
response.getWriter().write("hello async...");
System.out.println("副线程结束。。。"+Thread.currentThread()+"==>"+System.currentTimeMillis());
} catch (Exception e) {
}
}
});
System.out.println("主线程结束。。。"+Thread.currentThread()+"==>"+System.currentTimeMillis());
}public void service() throws Exception{
System.out.println(Thread.currentThread()+" service handler");
Thread.sleep(10000);
}
}