Primefaces推动怪异行为

Question

I am trying to get the "Counter" Primefaces Push sample working. It's actually working but i have to refresh the page once to get the push endpoint open. How can I have it open at the first page load ?

I am running this on Tomcat 8.0.24.

Here are the dependencies in the pom.xml :

<dependencies>
    <dependency>
        <groupId>org.apache.tomcat</groupId>
        <artifactId>servlet-api</artifactId>
        <version>6.0.44</version>
    </dependency>
    <dependency>
        <groupId>org.apache.myfaces.core</groupId>
        <artifactId>myfaces-api</artifactId>
        <version>2.2.8</version>
    </dependency>
    <dependency>
        <groupId>org.apache.myfaces.core</groupId>
        <artifactId>myfaces-impl</artifactId>
        <version>2.2.8</version>
    </dependency>
    <dependency>
        <groupId>org.primefaces</groupId>
        <artifactId>primefaces</artifactId>
        <version>5.2</version>
    </dependency>
    <dependency>
        <groupId>org.atmosphere</groupId>
        <artifactId>atmosphere-runtime</artifactId>
        <version>2.3.3</version>
    </dependency>
</dependencies>

The EndPoint:

@PushEndpoint("/counter")
public class CounterResource {

  @OnMessage(encoders = { JSONEncoder.class })
  public String onMessage(String count) {
    return count;
  }

  @OnOpen
  public void onOpen(RemoteEndpoint r, EventBus e) {
    System.out.println("CounterResource:onOpen PushEndpoint open!");
  }

  @OnClose
  public void onClose(RemoteEndpoint r, EventBus e) {
    System.out.println("CounterResource:onClose PushEndpoint closed!");
  }
}

The Managed Bean:

@ManagedBean
@ApplicationScoped
public class GlobalCounterView implements Serializable {

  private volatile int count;

  public int getCount() {
    return count;
  }

  public void setCount(int count) {
    this.count = count;
  }

  public void increment() {
    count++;

    EventBus eventBus = EventBusFactory.getDefault().eventBus();
    eventBus.publish("/counter", String.valueOf(count));
  }
}

The counter.xhtml page:

<h:body>
<h:form id="form">
    <h:outputText id="out" value="#{globalCounterView.count}"
        styleClass="ui-widget display" />

    <p:commandButton value="Click"
        actionListener="#{globalCounterView.increment}" />
</h:form>

<p:socket onMessage="handleMessage" channel="/counter" />

<script type="text/javascript">
    /* ugly workaround here
    window.onload = function() {
        if (!localStorage.justOnce) {
            localStorage.setItem("justOnce", "true");
            window.location.reload();
        }
    }*/

    function handleMessage(data) {
        $('.display').html(data);
    }
</script>

The web.xml:

<!-- JSF -->
<servlet>
    <servlet-name>Faces Servlet</servlet-name>
    <servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
</servlet>

<servlet-mapping>
    <servlet-name>Faces Servlet</servlet-name>
    <url-pattern>/faces/*</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>Faces Servlet</servlet-name>
    <url-pattern>*.xhtml</url-pattern>
</servlet-mapping>

<!-- Primefaces Push -->
<servlet>
    <servlet-name>Push Servlet</servlet-name>
    <servlet-class>org.primefaces.push.PushServlet</servlet-class>
    <init-param>
        <param-name>org.atmosphere.cpr.broadcasterCacheClass</param-name>
        <param-value>org.atmosphere.cache.UUIDBroadcasterCache</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
    <async-supported>true</async-supported>
</servlet>

<servlet-mapping>
    <servlet-name>Push Servlet</servlet-name>
    <url-pattern>/primepush/*</url-pattern>
</servlet-mapping>

When running this code I have no output when I first load the page and click the button, the value is incremented on the server side but the displayed value doesn't change since the endpoint is not open.

Then, when I refresh the page, the endpoint opens, the correct value of the counter is displayed and when I click the button, the value is incremented and displayed as intended.

I would greatly appreciate any help on this. Thank you for your assistance.

Answer 1

Changing the application server from Tomcat 8.0.24 to Tomcat 7.0.63 solved the problem !

I'm OK with that solution since I don't need Tomcat 8 absolutely.

And thanks to @Kukeltje I noticed some difference between Tomcat 7 and Tomcat 8 happening at the network level at first page load. I think the problem might come from atmosphere-runtime and I'll look further into that to satisfy my curiosity :)