Question

我正在开发一个Spring-MVC应用程序，我正在尝试将Chat功能与Cometd集成。我收到的错误是多个端点无法部署在同一路径中。

错误日志：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'cometDInitializer.Processor': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private org.cometd.bayeux.server.BayeuxServer com.journaldev.spring.chat.CometDInitializer$Processor.bayeuxServer; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'bayeuxServer' defined in class path resource [com/journaldev/spring/chat/CometDInitializer.class]: Invocation of init method failed; nested exception is java.lang.RuntimeException: javax.websocket.DeploymentException: Multiple Endpoints may not be deployed to the same path [/cometd]
    org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:292)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1185)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)

如果有人想要完整的错误日志Here it is on pastebin

CometdInitializer.java：

@Component
public class CometDInitializer implements ServletContextAware
{
    private ServletContext servletContext;

    @Bean(initMethod = "start", destroyMethod = "stop")
    public BayeuxServer bayeuxServer()
    {
        BayeuxServerImpl bean = new BayeuxServerImpl();
        bean.setTransports(new WebSocketTransport(bean), new JSONTransport(bean), new JSONPTransport(bean));
        servletContext.setAttribute(BayeuxServer.ATTRIBUTE, bean);
        bean.setOption(ServletContext.class.getName(), servletContext);
        bean.setOption("ws.cometdURLMapping", "/cometd/*");
        return bean;
    }

    public void setServletContext(ServletContext servletContext)
    {
        this.servletContext = servletContext;
    }

    @Component
    public static class Processor implements DestructionAwareBeanPostProcessor
    {
        @Inject
        private BayeuxServer bayeuxServer;
        private ServerAnnotationProcessor processor;

        @PostConstruct
        private void init()
        {
            this.processor = new ServerAnnotationProcessor(bayeuxServer);
        }

        @PreDestroy
        private void destroy()
        {
        }

        public Object postProcessBeforeInitialization(Object bean, String name) throws BeansException
        {
            processor.processDependencies(bean);
            processor.processConfigurations(bean);
            processor.processCallbacks(bean);
            return bean;
        }

        public Object postProcessAfterInitialization(Object bean, String name) throws BeansException
        {
            return bean;
        }

        public void postProcessBeforeDestruction(Object bean, String name) throws BeansException
        {
            processor.deprocessCallbacks(bean);
        }
    }
}

HelloService.java：

@Named
@Singleton
@Service("helloService")
public class HelloService
{
    @Inject
    private BayeuxServer bayeux;
    @Session
    private ServerSession serverSession;

    @PostConstruct
    public void init()
    {
    }

    @Listener("/service/hello")
    public void processHello(ServerSession remote, ServerMessage message)
    {
        System.out.println("We recieved a helo msg");
        Map<String, Object> input = message.getDataAsMap();
        String name = (String)input.get("name");

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

的application.js：

(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)
            {
                cometd.batch(function()
                {
                    cometd.subscribe('/hello', function(message)
                    {
                        $('#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);

的web.xml：

<servlet-mapping>
        <servlet-name>cometd</servlet-name>
        <url-pattern>/cometd/*</url-pattern>
    </servlet-mapping>
    <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.WebSocketTransport</param-value>
        </init-param>
        <init-param>
            <param-name>ws.cometdURLMapping</param-name>
            <param-value>/cometd/*</param-value>
        </init-param>

        <init-param>
            <param-name>logLevel</param-name>
            <param-value>3</param-value>
        </init-param>

        <load-on-startup>1</load-on-startup>
    </servlet>

修改的

最后，这是与来自mtn：archtype来自cometd的代码版本不匹配。以下文件有效：

@Component
public class BayeuxInitializer implements DestructionAwareBeanPostProcessor, ServletContextAware
{
    private BayeuxServer bayeuxServer;
    private ServerAnnotationProcessor processor;

    @Inject
    private void setBayeuxServer(BayeuxServer bayeuxServer)
    {
        this.bayeuxServer = bayeuxServer;
    }

    @PostConstruct
    private void init()
    {
        this.processor = new ServerAnnotationProcessor(bayeuxServer);
    }

    @PreDestroy
    private void destroy()
    {
    }

    public Object postProcessBeforeInitialization(Object bean, String name) throws BeansException
    {
        processor.processDependencies(bean);
        processor.processConfigurations(bean);
        processor.processCallbacks(bean);
        return bean;
    }

    public Object postProcessAfterInitialization(Object bean, String name) throws BeansException
    {
        return bean;
    }

    public void postProcessBeforeDestruction(Object bean, String name) throws BeansException
    {
        processor.deprocessCallbacks(bean);
    }

    @Bean(initMethod = "start", destroyMethod = "stop")
    public BayeuxServer bayeuxServer()
    {
        BayeuxServerImpl bean = new BayeuxServerImpl();
    //    bean.setTransports(new WebSocketTransport(bean), new JSONTransport(bean), new JSONPTransport(bean));
        return bean;
    }

    public void setServletContext(ServletContext servletContext)
    {
        servletContext.setAttribute(BayeuxServer.ATTRIBUTE, bayeuxServer);
    }
}

Answer 1

例外是由您的设计引起的：

自注册
以来，只能有一个BayeuxServer实例
```
bean.setOption("ws.cometdURLMapping", "/cometd/*");
```
只能为一个实例调用
。
有多个@Inject注释。因此生成了多个实例。每个@Inject

解决方案：添加@Singleton

@Bean(initMethod = "start", destroyMethod = "stop")
@Singleton
public BayeuxServer bayeuxServer()

现在只有一个BayeuxServer实例。所有@Inject都将获得相同的实例。

这仅适用于JSR330实现的实现。（对不起，春天不是！？）

单身人士的硬编码方式：

private static BayeuxServer beanInstance;
public static synchronized BayeuxServer bayeuxServer()
{
    if (beanInstance != null)
        return beanInstance;
    BayeuxServerImpl bean = new BayeuxServerImpl();
    bean.setTransports(new WebSocketTransport(bean), new JSONTransport(bean), new JSONPTransport(bean));
    servletContext.setAttribute(BayeuxServer.ATTRIBUTE, bean);
    bean.setOption(ServletContext.class.getName(), servletContext);
    bean.setOption("ws.cometdURLMapping", "/cometd/*");
    beanInstance = bean;
    return beanInstance;
}

提供多个端点的Cometd可能无法部署到同一路径[/ cometd]

1 个答案: