Question

我在使用cometD和Longpolling处理tomcat时遇到了问题。

我在firebug中看到所有请求都在ms区域，尽管民意调查应该保持至少1秒。服务器在ms时间内没有响应。

这是我在萤火虫中得到的：

8ms 
  dojo.j...ssed.js (Zeile 11610)
  POST http://localhost:8080/chatty/cometd/connect

  200 OK
                4ms 
            dojo.j...ssed.js (Zeile 11610)
        POST http://localhost:8080/chatty/cometd/connect

     200 OK
    2ms 
  dojo.j...ssed.js (Zeile 11610)
    POST http://localhost:8080/chatty/cometd/connect

我的web.xml

 <?xml version="1.0" encoding="UTF-8"?>
 <web-app xmlns="http://java.sun.com/xml/ns/javaee"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
     version="3.0">

<servlet>
    <servlet-name>cometd</servlet-name>
    <servlet-class>org.cometd.server.CometdServlet</servlet-class>
    <init-param>
        <param-name>transports</param-name>
        <param-value>org.cometd.websocket.server.JSONTransport</param-value>
    </init-param>
    <init-param>
        <param-name>allowedTransports</param-name>
        <param-value>org.cometd.server.transport.LongPollingTransport</param-value>
    </init-param>
    <init-param>
        <param-name>services</param-name>
        <param-value>com.xxxxx.StockPriceService</param-value>
    </init-param>
    <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>
    <init-param>
        <param-name>interval</param-name>
        <param-value>0</param-value>
    </init-param>
    <init-param>
        <param-name>long-polling.multiSessionInterval</param-name>
        <param-value>2000</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
    <async-supported>true</async-supported>
</servlet>
<servlet-mapping>
    <servlet-name>cometd</servlet-name>
    <url-pattern>/cometd/*</url-pattern>
</servlet-mapping>

<servlet>
    <servlet-name>initializer</servlet-name>
    <servlet-class>com.xxxxx.Initializer</servlet-class>
    <load-on-startup>2</load-on-startup>
</servlet>

<filter>
    <filter-name>cross-origin</filter-name>
    <filter-class>org.eclipse.jetty.servlets.CrossOriginFilter</filter-class>
</filter>
<filter-mapping>
    <filter-name>cross-origin</filter-name>
    <url-pattern>/cometd/*</url-pattern>
</filter-mapping>

<filter>
    <filter-name>continuation</filter-name>
    <filter-class>org.eclipse.jetty.continuation.ContinuationFilter</filter-class>
</filter>
<filter-mapping>
    <filter-name>continuation</filter-name>
    <url-pattern>/cometd/*</url-pattern>
</filter-mapping>

我的pom：安装 Maven的战争插件 org.cometd.javascript 的cometd-JavaScript的道场 org.mortbay.jetty 码头 - Maven的插件 10 /

<dependencies>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>servlet-api</artifactId>
        <version>2.5</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.cometd.java</groupId>
        <artifactId>bayeux-api</artifactId>
        <version>${cometd-version}</version>
    </dependency>
    <dependency>
        <groupId>org.cometd.javascript</groupId>
        <artifactId>cometd-javascript-dojo</artifactId>
        <version>${cometd-version}</version>
        <type>war</type>
    </dependency>
    <dependency>
        <groupId>org.cometd.java</groupId>
        <artifactId>cometd-java-server</artifactId>
        <version>${cometd-version}</version>
    </dependency>
    <dependency>
        <groupId>org.cometd.java</groupId>
        <artifactId>cometd-java-annotations</artifactId>
        <version>${cometd-version}</version>
    </dependency>
    <dependency>
        <groupId>org.cometd.java</groupId>
        <artifactId>cometd-java-client</artifactId>
        <version>${cometd-version}</version>
    </dependency>
    <dependency>
        <groupId>org.cometd.java</groupId>
        <artifactId>cometd-websocket-jetty</artifactId>
        <version>${cometd-version}</version>
        <exclusions>
            <exclusion>
                <groupId>org.cometd.java</groupId>
                <artifactId>cometd-java-client</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>org.eclipse.jetty</groupId>
        <artifactId>jetty-util</artifactId>
        <version>${jetty-version}</version>
    </dependency>
    <dependency>
        <groupId>org.eclipse.jetty</groupId>
        <artifactId>jetty-jmx</artifactId>
        <version>${jetty-version}</version>
    </dependency>
    <dependency>
        <groupId>org.eclipse.jetty</groupId>
        <artifactId>jetty-continuation</artifactId>
        <version>${jetty-version}</version>
    </dependency>
    <dependency>
        <groupId>org.eclipse.jetty</groupId>
        <artifactId>jetty-websocket</artifactId>
        <version>${jetty-version}</version>
    </dependency>
    <dependency>
        <groupId>org.eclipse.jetty</groupId>
        <artifactId>jetty-servlets</artifactId>
        <version>${jetty-version}</version>
        <exclusions>
            <exclusion>
                <groupId>org.eclipse.jetty</groupId>
                <artifactId>jetty-client</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>${slf4j-version}</version>
    </dependency>
</dependencies>

我确实想念longpoll配置吗？

Answer 1

您的web.xml确实是错误的。

首先，您无需指定transports＆lt; init-param＆gt;如果您只想使用long-polling传输。此参数适用于websocket等其他传输。这解释为here。

参数allowedTransports指定传输名称，而不是完全限定的类名。这解释为here。

services参数仅由AnnotationCometdServlet读取，如here所述（参见第6.4.2.3.4节）。

查看primer以设置初始Web应用程序，然后按照tutorials。

Answer 2

web.xml中的过滤器必须标记为true 例如org.eclipse.jetty.continuation.ContinuationFilter

Answer 3

我不知道你是否解决了问题。我使用Faye Browser客户端（JS）遇到了同样的问题。在我的情况下，当我在项目中添加一个新的Transport类并且将它包含在我的web.xml中时开始工作。

见下文：

package org.foo.bar.http.transports;

import java.util.Enumeration;

import java.io.IOException;
import java.text.ParseException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.cometd.bayeux.server.ServerMessage;
import org.cometd.server.BayeuxServerImpl;
import org.cometd.server.ServerSessionImpl;
import org.cometd.server.transport.LongPollingTransport;


public class CrossOriginLongPollingTransport extends LongPollingTransport
{
    public final static String PREFIX = "long-polling-cross-origin.json";
    public final static String NAME = "cross-origin-long-polling";
    public final static String MIME_TYPE_OPTION = "mimeType";

    private boolean _jsonDebug = false;
    private String _mimeType = "application/json;charset=UTF-8";

    public CrossOriginLongPollingTransport(BayeuxServerImpl bayeux)
    {
        super(bayeux, NAME);
        setOptionPrefix(PREFIX);
    }

    @Override
    protected boolean isAlwaysFlushingAfterHandle()
    {
        return false;
    }

    @Override
    protected void init()
    {
        super.init();
        _jsonDebug = getOption(JSON_DEBUG_OPTION, _jsonDebug);
        _mimeType = getOption(MIME_TYPE_OPTION, _mimeType);
    }

    @Override
    public boolean accept(HttpServletRequest request)
    {
        return "POST".equals(request.getMethod());
    }

    @Override
    protected ServerMessage.Mutable[] parseMessages(HttpServletRequest request) throws IOException, ParseException
    {
        String charset = request.getCharacterEncoding();
        if (charset == null)
            request.setCharacterEncoding("UTF-8");
        String contentType = request.getContentType();
        if (contentType == null || contentType.startsWith("application/json"))
            return parseMessages(request.getReader(), _jsonDebug);
        else if (contentType.startsWith("application/x-www-form-urlencoded")) {
            return parseMessages(request.getParameterValues(MESSAGE_PARAM));
        } else
            throw new IOException("Invalid Content-Type " + contentType);
    }

    @Override
    protected ServletOutputStream beginWrite(HttpServletRequest request, HttpServletResponse response, ServerSessionImpl session) throws IOException
    {
        response.setContentType(_mimeType);
        ServletOutputStream output = response.getOutputStream();
        output.write('[');
        return output;
    }

    @Override
    protected void endWrite(ServletOutputStream output, ServerSessionImpl session) throws IOException
    {
        output.write(']');
        output.close();
    }
}

之后，包含在你的web.xml中：

    <init-param>
        <param-name>transports</param-name>
        <param-value>org.cometd.websocket.server.WebSocketTransport,org.foo.bar.http.transports.CrossOriginLongPollingTransport</param-value>
    </init-param>
    <init-param>
        <param-name>allowedTransports</param-name>
        <param-value>cross-origin-long-polling,long-polling,callback-polling,websocket</param-value>
    </init-param>

它对我有用，我希望你也可以帮忙。

最佳。

CometD和Tomcat没有使用Long-Polling

3 个答案: