java - cometd : Cometd servlet does not support asynchronous on tomcat-6ren

java - cometd : Cometd servlet does not support asynchronous on tomcat

转载作者：行者123 更新时间：2023-11-28 22:55:03

我正在开发我目前正在使用的 Spring-MVC 应用程序在 Apache tomcat 7.0.55 上使用 Cometd 实现聊天功能。我有基本的代码在运行，我可以通过 channel 发送消息并接收它们。加载页面时，我收到一条错误消息，指出 cometd servlet 不支持异步操作。
当我阅读文档时，我发现，有必要使用 NIO 连接器配置 tomcat，我已经完成并放置了 <async-supported>在 web.xml 中，但我仍然不断收到该错误。这是为什么？寻找一些解决方案后，我发现了一个问题，那说需要配置tomcat，并链接cometd文档，它反过来只链接 Apache-tomcat主页(死胡同)。

任何人都可以告诉我必须进行哪些修改才能允许 websockets。非常感谢。

错误日志:

SEVERE: Servlet.service() for servlet [cometd] in context with path [] threw exception
java.lang.IllegalStateException: A filter or servlet of the current chain does not support asynchronous operations.
    at org.apache.catalina.connector.Request.startAsync(Request.java:1658)
    at org.apache.catalina.connector.RequestFacade.startAsync(RequestFacade.java:1029)
    at javax.servlet.ServletRequestWrapper.startAsync(ServletRequestWrapper.java:379)
    at javax.servlet.ServletRequestWrapper.startAsync(ServletRequestWrapper.java:379)
    at org.springframework.security.web.context.HttpSessionSecurityContextRepository$Servlet3SaveToSessionRequestWrapper.startAsync(HttpSessionSecurityContextRepository.java:246)

整个 web.xml :

   <?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns="http://java.sun.com/xml/ns/javaee"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
         http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0"
        >
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>/WEB-INF/spring/root-context.xml,/WEB-INF/spring/appServlet/security-applicationContext.xml
        </param-value>
    </context-param>

    <session-config>
        <session-timeout>1440</session-timeout>
    </session-config>
    <listener>
        <listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>

    </listener>
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <servlet>
        <servlet-name>cometd</servlet-name>
        <servlet-class>org.cometd.server.CometDServlet</servlet-class>
        <async-supported>true</async-supported>
    </servlet>
    <servlet-mapping>
        <servlet-name>cometd</servlet-name>
        <url-pattern>/cometd/*</url-pattern>
    </servlet-mapping>

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


    <filter>
        <filter-name>springSecurityFilterChain</filter-name>
        <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
        <async-supported>true</async-supported>
        <init-param>
            <param-name>contextAttribute</param-name>
            <param-value>org.springframework.web.context.WebApplicationContext.ROOT</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>springSecurityFilterChain</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
    <servlet>
        <servlet-name>403Jsp</servlet-name>
        <jsp-file>/WEB-INF/views/error/403.jsp</jsp-file>
    </servlet>
    <servlet-mapping>
        <servlet-name>403Jsp</servlet-name>
        <url-pattern>/403</url-pattern>
    </servlet-mapping>
    <listener>
        <listener-class>org.springframework.security.web.session.HttpSessionEventPublisher</listener-class>
    </listener>
    <servlet>
        <servlet-name>appServlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>/WEB-INF/spring/appServlet/servlet-context.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
        <async-supported>true</async-supported>
    </servlet>
    <servlet-mapping>
        <servlet-name>appServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
    <servlet-mapping>
        <servlet-name>default</servlet-name>
        <url-pattern>*.png</url-pattern>
    </servlet-mapping>
    <servlet-mapping>
        <servlet-name>default</servlet-name>
        <url-pattern>*.jpg</url-pattern>
    </servlet-mapping>
    <filter>
        <filter-name>encodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <async-supported>true</async-supported>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
        <init-param>
            <param-name>forceEncoding</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>encodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <filter>
        <filter-name>ExpiresFilter</filter-name>
        <filter-class>org.apache.catalina.filters.ExpiresFilter</filter-class>
        <init-param>
            <param-name>ExpiresByType text/html</param-name>
            <param-value>access plus 1 seconds</param-value>
        </init-param>
        <init-param>
            <param-name>ExpiresByType image</param-name>
            <param-value>access plus 10 weeks</param-value>
        </init-param>
        <init-param>
            <param-name>ExpiresByType text/css</param-name>
            <param-value>access plus 10 weeks</param-value>
        </init-param>
        <init-param>
            <param-name>ExpiresByType application/javascript</param-name>
            <param-value>access plus 10 weeks</param-value>
        </init-param>
        <init-param>
            <param-name>ExpiresByType text/javascript</param-name>
            <param-value>access plus 10 weeks</param-value>
        </init-param>
        <init-param>
            <param-name>ExpiresByType font/truetype</param-name>
            <param-value>access plus 10 weeks</param-value>
        </init-param>
        <init-param>
            <param-name>ExpiresByType font/opentype</param-name>
            <param-value>access plus 10 weeks</param-value>
        </init-param>
        <init-param>
            <param-name>ExpiresByType application/x-font-woff</param-name>
            <param-value>access plus 10 weeks</param-value>
        </init-param>
        <init-param>
            <param-name>ExpiresByType application/vnd.ms-fontobject</param-name>
            <param-value>access plus 10 weeks</param-value>
        </init-param>
        <init-param>
            <param-name>ExpiresByType image/svg+xml</param-name>
            <param-value>access plus 10 weeks</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>ExpiresFilter</filter-name>
        <url-pattern>/*</url-pattern>
        <dispatcher>REQUEST</dispatcher>
    </filter-mapping>

    <!--     
      <error-page>
      <error-code>403</error-code>
        <location>/WEB-INF/views/error/403.jsp</location>
      </error-page>

      <error-page>
      <error-code>404</error-code>
        <location>/WEB-INF/views/error/404.jsp</location>
      </error-page>

      <error-page>
          <location>/WEB-INF/views/error/general.jsp</location>
      </error-page>
 -->

</web-app>

cometd 配置:

import org.cometd.annotation.ServerAnnotationProcessor;
import org.cometd.bayeux.server.BayeuxServer;
import org.cometd.server.BayeuxServerImpl;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.DestructionAwareBeanPostProcessor;
import org.springframework.context.annotation.Bean;
import org.springframework.stereotype.Component;
import org.springframework.web.context.ServletContextAware;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;
import javax.inject.Inject;
import javax.servlet.ServletContext;

@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() {
        return new BayeuxServerImpl();
    }

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

聊天服务实现:

@Named
@Singleton
@Service
public class ChatServiceImpl {
    @Inject
    private BayeuxServer bayeux;

    @Session
    private ServerSession serverSession;

 @PostConstruct
    public void init() {
    }

 @Listener(value = "/service/online")
    public void OnlineNotifications(ServerSession remote, ServerMessage.Mutable message) { 
// method body
}

// and other listeners, omitted.

POM.xml 中的 Cometd 依赖项

 <!-- Cometd dependencies -->
        <dependency>
            <groupId>org.cometd.java</groupId>
            <artifactId>bayeux-api</artifactId>
            <version>3.0.4</version>
        </dependency>
        <dependency>
            <groupId>org.cometd.javascript</groupId>
            <artifactId>cometd-javascript-jquery</artifactId>
            <version>3.0.4</version>
            <type>war</type>
        </dependency>
        <dependency>
            <groupId>org.cometd.java</groupId>
            <artifactId>cometd-java-server</artifactId>
            <version>3.0.4</version>
        </dependency>

        <dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-client</artifactId>
            <version>9.2.9.v20150224</version>
        </dependency>

        <dependency>
            <groupId>org.cometd.java</groupId>
            <artifactId>cometd-java-client</artifactId>
            <version>3.0.4</version>
        </dependency>


        <dependency>
            <groupId>org.cometd.java</groupId>
            <artifactId>cometd-java-annotations</artifactId>
            <version>3.0.4</version>
        </dependency>
        <dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-servlets</artifactId>
            <version>9.2.9.v20150224</version>
        </dependency>

Tomcat 的 conf.xml :

<Connector connectionTimeout="20000" maxThreads="1000" port="8080" protocol="org.apache.coyote.http11.Http11NioProtocol" redirectPort="8443"/>

 <Connector port="8443" protocol="HTTP/1.1" SSLEnabled="true" maxThreads="150" 
               scheme="https" secure="true" clientAuth="false"  sslProtocol="TLS" maxHttpHeaderSize="8192" connectionTimeout="20000"
               keystoreFile="/home/username/.keystore" keystorePass="password" />

我也尝试在端口 8443 上使用 NIO 协议(protocol)，但也没有用。我试过使用 Apache tomcat 版本 8，我遇到了同样的错误，不是一次，而是每隔几秒钟。

更新 FasterXMl 抛出错误

Sep 08, 2015 2:06:17 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [appServlet] in context with path [] threw exception [Request processing failed; nested exception is java.lang.IllegalStateException: Failed to instantiate standard serializer (of type com.fasterxml.jackson.databind.ser.std.NullSerializer): Class com.fasterxml.jackson.databind.ser.BasicSerializerFactory can not access a member of class com.fasterxml.jackson.databind.ser.std.NullSerializer with modifiers "private"] with root cause
java.lang.IllegalAccessException: Class com.fasterxml.jackson.databind.ser.BasicSerializerFactory can not access a member of class com.fasterxml.jackson.databind.ser.std.NullSerializer with modifiers "private"
    at sun.reflect.Reflection.ensureMemberAccess(Reflection.java:102)
    at java.lang.Class.newInstance(Class.java:436)
    at com.fasterxml.jackson.databind.ser.BasicSerializerFactory.findSerializerByLookup(BasicSerializerFactory.java:299)
    at com.fasterxml.jackson.databind.ser.BeanSerializerFactory._createSerializer2(BeanSerializerFactory.java:210)
    at com.fasterxml.jackson.databind.ser.BeanSerializerFactory.createSerializer(BeanSerializerFactory.java:152)
    at com.fasterxml.jackson.databind.SerializerProvider._createUntypedSerializer(SerializerProvider.java:1077)
    at com.fasterxml.jackson.databind.SerializerProvider._createAndCacheUntypedSerializer(SerializerProvider.java:1037)
    at com.fasterxml.jackson.databind.SerializerProvider._findExplicitUntypedSerializer(SerializerProvider.java:1018)
    at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.hasSerializerFor(DefaultSerializerProvider.java:336)
    at com.fasterxml.jackson.databind.ObjectMapper.canSerialize(ObjectMapper.java:1996)
    at org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.canWrite(AbstractJackson2HttpMessageConverter.java:162)
    at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.getProducibleMediaTypes(AbstractMessageConverterMethodProcessor.java:204)
    at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:122)
    at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:101)
    at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.handleReturnValue(RequestResponseBodyMethodProcessor.java:167)
    at org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue(HandlerMethodReturnValueHandlerComposite.java:71)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:126)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:776)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:705)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:857)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:620)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.catalina.filters.ExpiresFilter.doFilter(ExpiresFilter.java:1179)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:85)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:316)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:126)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:90)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:114)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:122)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.authentication.rememberme.RememberMeAuthenticationFilter.doFilter(RememberMeAuthenticationFilter.java:157)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:168)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:48)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:205)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:120)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:64)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:53)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.session.ConcurrentSessionFilter.doFilter(ConcurrentSessionFilter.java:133)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:91)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:330)
    at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:213)
    at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:176)
    at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:344)
    at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:261)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1736)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1695)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:745)

最佳答案

您当前的 web.xml缺少 <async-supported>true</async-supported>链中至少有 2 个过滤器。

CharacterEncoding过滤器以及 ExpiresFilter .由于 /*，两者都在所有链中映射所以应该有async-supported设置为 true .

关于java - cometd : Cometd servlet does not support asynchronous on tomcat，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/29622732/

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