Question

我正在尝试使用CometD，因为我需要一些经验背景来进行各种推送技术之间的技术比较。

我终于设法在我的Tomcat（v7.0）中运行示例代码。

现在我有一种奇怪的行为，我拼命地试图找出我做错了什么。

以下是我的观察：

连接循环：

我正在与客户端进行无休止的连接循环。

请求：

[{"channel":"/meta/connect","connectionType":"long-polling","id":"19","clientId":"f1le33y91f6pa71f39z52km87yp"}]

响应：

[{"id":"19","successful":true,"advice":{"interval":2000,"reconnect":"retry","multiple-clients":true,"timeout":60000},"channel":"/meta/connect"}]

有趣的是，Listener-callback事件实际上发生了

 cometd.addListener('/meta/handshake', _metaHandshake);

客户端连接请求卡住了

这主要发生在重新启动我的Tomcat服务器之后。我可以看到成功订阅2个频道：

请求

[{"version":"1.0","minimumVersion":"0.9","channel":"/meta/handshake","supportedConnectionTypes":["long-polling","callback-polling"],"advice":{"timeout":60000,"interval":0},"id":"1"}]

响应

[{"id":"1","minimumVersion":"1.0","supportedConnectionTypes":["callback-polling","long-polling"],"successful":true,"channel":"/meta/handshake","clientId":"11tnpjnmkqo3tf64zcvufuqbtv","version":"1.0"}]

请求

[{"channel":"/meta/subscribe","subscription":"/hello","id":"2","clientId":"11tnpjnmkqo3tf64zcvufuqbtv"},{"channel":"/service/hello","data":{"name":"World"},"id":"3","clientId":"11tnpjnmkqo3tf64zcvufuqbtv"}]

响应

[{"id":"2","subscription":"/hello","successful":true,"channel":"/meta/subscribe"},{"id":"3","successful":true,"channel":"/service/hello"}]

这一次之后的电话卡住并永远消失。

... abd这是我的代码

客户端

(function($)
 {
   var cometd = $.cometd;

$(document).ready(function()
{
    function _connectionEstablished()
    {
        $('#body').append('<div>CometD Connection Established</div>');
    }

    function _connectionBroken()
    {
        $('#body').append('<div>CometD Connection Broken</div>');
    }

    function _connectionClosed()
    {
        $('#body').append('<div>CometD Connection Closed</div>');
    }

    // Function that manages the connection status with the Bayeux server
    var _connected = false;
    function _metaConnect(message)
    {
        if (cometd.isDisconnected())
        {
            _connected = false;
            _connectionClosed();
            return;
        }

        var wasConnected = _connected;
        _connected = message.successful === true;
        if (!wasConnected && _connected)
        {
            _connectionEstablished();
        }
        else if (wasConnected && !_connected)
        {
            _connectionBroken();
        }
    }

    // Function invoked when first contacting the server and
    // when the server has lost the state of this client
    function _metaHandshake(handshake)
    {
        if (handshake.successful === true)
        {
           // interesting enough: that event is triggered
            alert('event occured');
            cometd.batch(function()
            {
                // that function is called and produces a corresponding request to the server
                cometd.subscribe('/hello', function(message)
                {
                    // that one never happens... 
                    $('#body').append('<div>Server Says: ' + message.data.greeting + '</div>');
                });
                // Publish on a service channel since the message is for the server only
                cometd.publish('/service/hello', { name: 'World' });
            });
        }
    }

    // Disconnect when the page unloads
    $(window).unload(function()
    {
        cometd.disconnect(true);
    });

    var cometURL = location.protocol + "//" + location.host + config.contextPath + "/cometd";
    cometd.configure({
        url: cometURL,
        logLevel: 'debug'
    });

    cometd.addListener('/meta/handshake', _metaHandshake);
    cometd.addListener('/meta/connect', _metaConnect);

    cometd.handshake();
});
})(jQuery);

服务器

请注意，这与分发包中的示例差不多是1：1！

public class HelloService extends AbstractService
{
public HelloService(BayeuxServer bayeux)
{
    super(bayeux, "hello");
    addService("/service/hello", "processHello");
}

public void processHello(ServerSession remote, Message message)
{
    Map<String, Object> input = message.getDataAsMap();
    String name = (String)input.get("name");

    Map<String, Object> output = new HashMap<String, Object>();
    output.put("greeting", "Hello, " + name);
    remote.deliver(getServerSession(), "/hello", output, null);
}

}

Web.xml文件

http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd” 版本= “2.5” ＆GT;

<servlet>
    <servlet-name>cometd</servlet-name>
    <servlet-class>org.cometd.server.CometdServlet</servlet-class>
    <async-supported>true</async-supported>
    <init-param>
        <param-name>timeout</param-name>
        <param-value>60000</param-value>
    </init-param>
    <init-param>
        <param-name>logLevel</param-name>
        <param-value>3</param-value>
    </init-param>
</servlet>
<servlet-mapping>
    <servlet-name>cometd</servlet-name>
    <url-pattern>/cometd/*</url-pattern>
</servlet-mapping>

也许我只是做了一件完全错误的事情，但我开始有点绝望了。帮助将受到高度赞赏。

CometD / jQuery客户端错误402 ::未知客户端

0 个答案: