Glassfish 中的 Java EE WebSockets 可能的“僵尸”连接

Posted 2023-02-16

【中文标题】Glassfish 中的 Java EE WebSockets 可能的“僵尸”连接

【英文标题】：Java EE WebSockets in Glassfish possible "zombie" connection

【发布时间】：2017-09-22 16:33:26

【问题描述】：

我正在学习用于 WebSockets 的 Java API，我有一个问题。 每次我连接到端点时，应用程序都会创建 2 个连接，第一个连接会引发此异常：

Info:   websocketbot was successfully deployed in 3,174 milliseconds.
Info:   (@OnOpen method) Connection opened.
Info:   (@OnOpen method) Opened connections: 1
Warning:   Already set read listener
java.lang.IllegalStateException: Already set read listener
    at org.apache.catalina.connector.InputBuffer.setReadListener(InputBuffer.java:303)
    at org.apache.catalina.connector.CoyoteInputStream.setReadListener(CoyoteInputStream.java:312)
    at org.glassfish.tyrus.servlet.TyrusHttpUpgradeHandler.init(TyrusHttpUpgradeHandler.java:105)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:777)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:413)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:283)
    at com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:459)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:167)
    at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:206)
    at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:180)
    at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:235)
    at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:283)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:200)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:132)
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:111)
    at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77)
    at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:536)
    at org.glassfish.grizzly.strategies.Abstractiostrategy.fireIOEvent(AbstractIOStrategy.java:112)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:117)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:56)
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:137)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:591)
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:571)
    at java.lang.Thread.run(Thread.java:748)

Info:   Connection opened.
Info:   Opened connections: 2

我的端点类：

package pckg;

import java.util.logging.Level;
import java.util.logging.Logger;
import javax.websocket.OnClose;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.server.ServerEndpoint;

@ServerEndpoint("/echo")
public class TestEndpoint 

    private static final Logger logger = Logger.getLogger("TestEndpoint");

    @OnOpen
    public void open(Session session) 
        logger.log(Level.INFO, "(@OnOpen method) Connection opened.");
        logger.log(Level.INFO, "(@OnOpen method) Opened connections:" 
                + session.getOpenSessions().size());
    

    @OnClose
    public void close(Session session) 
        logger.log(Level.INFO, "(@OnClose method) Connection closed.");
        logger.log(Level.INFO, "(@OnClose method) Opened connections:" 
                + session.getOpenSessions().size());
    

当我关闭连接（例如关闭浏览器）时，只有一个会话实例被关闭。

当我实现@OnMessage 方法来接收消息和发送消息的方法时，我会收到每条消息两次。

我想问的是这是否应该发生。我正在使用过去遇到问题的 NetBeans 和 GlassFish 服务器。

PS：我还尝试了 Oracle 官方教程中的一个示例应用程序，名为“websocketbot”（一个聊天实现）。它的消息也会重复，即使它们显然不应该重复。我还必须添加一些代码以使其 100% 工作。

编辑：问题确实出在 GlassFish 上。在 WildFly 服务器上运行正常。

【问题讨论】：

你用javascript打开连接吗？

您也可以使用Payara Server 进行测试吗？它源自 GlassFish，如果它在 Payara Server 中工作，它很可能是 GlassFish 中的一个错误。

【参考方案1】：

我在打开 glassfish 的访问日志后遇到了类似的问题。这似乎是玻璃鱼中的一个错误。

https://github.com/payara/Payara/issues/70