Question

我有一个名为MyServlet的servlet。这个servlet绑定在我的web.xml文件中。这个servlet正在迭代我的Grails服务，并负责管理以ListenerService结尾的服务。如果是这样，它会初始化此服务的新Servlet。

我有以下监听服务：

ChatListenerService
NotificationListenerService
ThirdListenerService

这意味着我应该获得MyServlet生成的三个Servlet。当您查看输出时，您会看到第一个Servlet正在生成三次，第二个生成两次，第三个Service生成一次。

以下是我得到的输出：

2013-10-25 13:05:50,460 [localhost-startStop-1] INFO  cpr.AtmosphereServlet  - AtmosphereServlet with native support for Tomcat 6/7 and JBossWeb Installed.
>>>>>>>>>>>>>>> been: test.ChatListenerService@41028653
2013-10-25 13:05:50,577 [localhost-startStop-1] INFO  handler.ReflectorServletProcessor  - Installing Servlet test.ChatListenerService
2013-10-25 13:05:50,577 [localhost-startStop-1] INFO  test.MyServlet  - registered chatListener as handler for /atmosphere/chat/*
>>>>>>>>>>>>>>> been: test.NotificationListenerService@70b005e0
2013-10-25 13:05:50,582 [localhost-startStop-1] INFO  handler.ReflectorServletProcessor  - Installing Servlet test.NotificationListenerService
2013-10-25 13:05:50,582 [localhost-startStop-1] INFO  handler.ReflectorServletProcessor  - Installing Servlet test.ChatListenerService
2013-10-25 13:05:50,582 [localhost-startStop-1] INFO  test.MyServlet  - registered notificationListener as handler for /atmosphere/notification/*
>>>>>>>>>>>>>>> been: test.ThirdListenerService@4cba9be9
2013-10-25 13:05:50,587 [localhost-startStop-1] INFO  handler.ReflectorServletProcessor  - Installing Servlet test.NotificationListenerService
2013-10-25 13:05:50,587 [localhost-startStop-1] INFO  handler.ReflectorServletProcessor  - Installing Servlet test.ChatListenerService
2013-10-25 13:05:50,587 [localhost-startStop-1] INFO  handler.ReflectorServletProcessor  - Installing Servlet test.ThirdListenerService
2013-10-25 13:05:50,587 [localhost-startStop-1] INFO  test.MyServlet  - registered pedigreeListener as handler for /atmosphere/third/*
2013-10-25 13:05:50,587 [localhost-startStop-1] INFO  test.MyServlet  - Initialized MyServlet

这里出了什么问题？因为我只迭代每个服务一次，我不明白为什么服务不止一次生成。我该怎么办？

我的web.xml：

<servlet>
    <description>MyServlet</description>
    <servlet-name>MyServlet</servlet-name>
    <servlet-class>test.MyServlet</servlet-class>
    <load-on-startup>0</load-on-startup>

    <!-- If you want to use Servlet 3.0 -->
    <async-supported>true</async-supported>

    <init-param>
        <param-name>org.atmosphere.useNative</param-name>
        <param-value>true</param-value>
    </init-param>

    <init-param>
        <param-name>org.atmosphere.cpr.AtmosphereInterceptor</param-name>
        <param-value>org.atmosphere.interceptor.AtmosphereResourceLifecycleInterceptor,org.atmosphere.interceptor.HeartbeatInterceptor,org.atmosphere.client.TrackMessageSizeInterceptor</param-value>
    </init-param>

    <init-param>
        <param-name>org.atmosphere.cpr.broadcaster.shareableThreadPool</param-name>
        <param-value>true</param-value>
    </init-param>

    <init-param>
           <param-name>org.atmosphere.useWebSocketAndServlet3</param-name>
           <param-value>true</param-value>
    </init-param>

    <init-param>
        <param-name>org.atmosphere.cpr.Broadcaster.writeTimeout</param-name>
        <param-value>30000</param-value>
    </init-param>

    <init-param>
        <param-name>org.atmosphere.cpr.sessionSupport</param-name>
        <param-value>true</param-value>
    </init-param>

    <init-param>
        <param-name>org.atmosphere.cpr.broadcasterCacheClass</param-name>
        <param-value>org.atmosphere.cache.UUIDBroadcasterCache</param-value>
    </init-param>
</servlet>
<servlet-mapping>
    <servlet-name>MyServlet</servlet-name>
    <url-pattern>/atmosphere/*</url-pattern>
</servlet-mapping>

myService类：

class MyServlet extends MeteorServlet {

    @Override
     void init(ServletConfig sc) throws ServletException {
         super.init(sc)

        def webApplicationContext = WebApplicationContextUtils.getWebApplicationContext sc.servletContext

        def grailsApplication = webApplicationContext.getBean("grailsApplication")

        def services = grailsApplication.getArtefacts "Service"

        def suffix = "Listener"

        services.each { serviceClass ->
            def serviceName = serviceClass.logicalPropertyName
            if(serviceName.endsWith(suffix)) {
                def prefix = serviceName - suffix

                def bean = webApplicationContext.getBean(serviceClass.clazz)

                def servlet = serviceClass.clazz

                String servletClass = bean.class.getName()
                ReflectorServletProcessor rsp = new ReflectorServletProcessor(bean)
                rsp.setServletClassName(servletClass)

                framework.addAtmosphereHandler("/atmosphere/${prefix}/*", rsp).initAtmosphereHandler(sc)        

                log.info "registered $serviceName as handler for /atmosphere/${prefix}/*"
            }
        }

        log.info "Initialized MyServlet"

     }

我的ChatListenerService（另一个看起来类似）：

class ChatListenerService extends HttpServlet {


    static transactional = false

        @Override
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException {
          Meteor meteor = Meteor.build(request)
          ...
        }

    @Override
    public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException {
          Meteor meteor = Meteor.build(request)
          ...
        }
...
}

Answer 1

您每次都在致电initAtmosphereHandler

framework.addAtmosphereHandler("/atmosphere/${prefix}/*", rsp).initAtmosphereHandler(sc)

addAtmosphereHandler()方法只是注册服务。对initAtmosphereHandler的调用实际上实例化了它们。 javadoc简单地说

初始化AtmosphereServletProcessor。

所以第一次循环迭代，你有一个注册服务。在第二次迭代中，您有两个注册的服务。在第三次迭代中，您有三个注册的服务。在每次迭代中，都会实例化所有服务。

摆脱initAtmosphereHandler调用，并在each循环之外执行。

Servlet不止一次被初始化？

1 个答案: