Java 非法尝试将集合与两个打开的会话关联

我有一个J2EEWeb应用程序，我正在使用hibernate和struts2框架。 该项目在本地服务器上运行良好，但当我将应用程序上载到web上，并且有更多用户同时访问该应用程序时，会引发以下错误：

Illegal attempt to associate a collection with two open sessions

突然整个hibernate系统崩溃了，我无法执行任何查询。 以下是stacktrace：

'org.hibernate.HibernateException: Illegal attempt to associate a collection with two open sessions
    at org.hibernate.collection.AbstractPersistentCollection.setCurrentSession(AbstractPersistentCollection.java:432)
    at org.hibernate.event.def.WrapVisitor.processCollection(WrapVisitor.java:67)
    at org.hibernate.event.def.AbstractVisitor.processValue(AbstractVisitor.java:124)
    at org.hibernate.event.def.WrapVisitor.processValue(WrapVisitor.java:121)
    at org.hibernate.event.def.AbstractVisitor.processEntityPropertyValues(AbstractVisitor.java:78)
    at org.hibernate.event.def.DefaultFlushEntityEventListener.wrapCollections(DefaultFlushEntityEventListener.java:218)
    at org.hibernate.event.def.DefaultFlushEntityEventListener.onFlushEntity(DefaultFlushEntityEventListener.java:152)
    at org.hibernate.event.def.AbstractFlushingEventListener.flushEntities(AbstractFlushingEventListener.java:219)
    at org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(AbstractFlushingEventListener.java:99)
    at org.hibernate.event.def.DefaultAutoFlushEventListener.onAutoFlush(DefaultAutoFlushEventListener.java:58)
    at org.hibernate.impl.SessionImpl.autoFlushIfRequired(SessionImpl.java:1175)
    at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1251)
    at org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
    at org.hibernate.impl.AbstractQueryImpl.uniqueResult(AbstractQueryImpl.java:859)
    at com.hposg.login.LoginFactory.doLogin(LoginFactory.java:31)
    at com.hposg.controller.struts.LoginAction.execute(LoginAction.java:50)
    at sun.reflect.GeneratedMethodAccessor489.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:616)
    at com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:441)
    at com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:280)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:243)
    at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:165)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:252)
    at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:122)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:179)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:94)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:235)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:89)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:130)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:267)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:126)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:138)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:165)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:179)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:176)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:237)
    at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52)
    at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:488)
    at org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:395)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:857)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
    at java.lang.Thread.run(Thread.java:636)

以下是导致此问题的代码：

public static Player doLogin(String ID, String pass) throws LoginException , BanedUser{

        Session session = HibernateUtil.getSessionFactory().getCurrentSession();
        session.beginTransaction();

        Player player = (Player) session.createQuery(
                "from Player as player where player.loginName = " + "'" + ID
                        + "' and player.passWord ='" + pass + "'")
                .uniqueResult();

        if (player == null)
            throw new LoginException();
        else if (!player.getIsActive())
            throw new BanedUser();

        UserSession.getInstance();
        UserSession.addPlayer(player);

        session.beginTransaction().commit();

        return player;
    }

错误不规则地发生（一周一次，每隔一天等），你知道是什么导致了这个问题吗

---

这是我的hibernate.cfg.xml：

<?xml version='1.0' encoding='utf-8'?>

com.mysql.jdbc.Driver
jdbc：mysql://localhost/hposg?characterEncoding=UTF-8
根
1.
真的
org.hibernate.dialogue.mysqldialogue
线
org.hibernate.cache.NoCacheProvider
更新

以下是我使用hibernate策略的登录示例：

try {
            Player player = LoginFactory.doLogin(username.toLowerCase(),
                    password);

            Session lSession = HibernateUtil.getSessionFactory()
                    .getCurrentSession();
            lSession.beginTransaction();

            lSession.lock(player, LockMode.NONE);
            player.getInbox().size();
            Collection<Message> unreadMsgs = lSession
                    .createQuery(
                            "FROM Message message WHERE Respondent.id='"
                                    + player.getId()
                                    + "' AND message.isRead=false").list();

            lSession.getTransaction().commit();

            UserSession.getInstance().addPlayer(player);
            Map session = (Map) ActionContext.getContext().get("session");
            session.put("UID", username.toLowerCase());
            session.put("TYPE", "PLAYER");
            session
                    .put("NAME", player.getName() + " "
                            + player.getFamily());
            session.put("UNREADMSGS", unreadMsgs.size());
            session.put("LAST_VIEWED_GAME_ID", 0);
            return SUCCESS;
        } catch (LoginException a) {
            addActionError(a.getMessage());
            return "error";
        } catch (Exception a) {
            addActionError(e.getMessage());
            return "error";
        }

试试看{
Player=LoginFactory.doLogin（用户名.toLowerCase（），
密码）；
会话lSession=HibernateUtil.getSessionFactory（）
.getCurrentSession（）；
lSession.beginTransaction（）；
lSession.lock（播放器，LockMode.NONE）；
player.getInbox（）.size（）；
集合未读dmsgs=lSession
.createQuery(
“来自响应者id为“”的消息”
+player.getId（）
+“'和message.isRead=false”）.list（）；
lSession.getTransaction（）.commit（）；
UserSession.getInstance（）.addPlayer（播放器）；
映射会话=（映射）ActionContext.getContext（）.get（“会话”）；
session.put（“UID”，username.toLowerCase（））；
会话。put（“类型”、“玩家”）；
一场
.put（“名称”，player.getName（）+“”
+player.getFamily（））；
session.put（“UNREADMSGS”，UNREADMSGS.size（））；
session.put（“上次查看的游戏ID”，0）；
回归成功；
}捕获（LoginException a）{
addActionError（a.getMessage（））；
返回“错误”；
}捕获（例外a）{
addActionError（如getMessage（））；
返回“错误”；
}

我错过了什么吗？

---

有什么想法吗？

您的代码显示您创建了2个事务。。。。试试这个：-

public static Player doLogin(String ID, String pass) throws LoginException , BanedUser{

        Session session = HibernateUtil.getSessionFactory().getCurrentSession();
        Transaction tx = session.beginTransaction();

        ...

        tx.commit();

        return player;
    }

---

请确认您正在使用XWork操作类作为Springbean？ 如果是这样的话，可能您忘记了遵循Struts2/Spring中的指令，即当您将actionbean作为springbean（在依赖注入控制器中）时。。。 您需要将bean声明为非单例！ 在声明中，确保您具有singleton=“false”属性

---

如果你忘了做这个会怎么样？一个用户访问相同的操作，一切正常。超过1个用户访问您的bean，您在单例bean中有竞争条件。我怀疑你的应用程序中确实发生了这种情况。

显然，使用merge可能会解决这个问题

myInstance = (myInstanceClass) Session.merge(myInstance);

---

这有什么用？UserSession.getInstance（）；UserSession.addPlayer（播放器）；显示您的

LoginAction

和

hibernate.cfg.xml

。UserSession只是一个包含已登录用户哈希映射的类。addPlayer（）中的代码是线程安全的吗？事实上，这个类与hibernate无关，我不保存这个对象。它只是一个容器，用来存放在线用户。但你的观点似乎是一个有希望的线索！我根本没有考虑整个项目中的线程安全问题。你还有什么特别的建议吗？天哪！似乎很有道理。你说得对，伙计。（我们应该和这部分的程序员做些生意！：D）。但出于好奇，为什么每个doLogin都不会发生这种情况，错误也会不规则地发生？不幸的是，问题仍然存在：（我检查了代码的每个部分，并将所有会话都更改了。beginTransaction（）.commit（）；改为session.getTransaction（）.commit（）），但这种情况再次发生。谢谢Daniel，实际上我根本没有使用spring，但我确实使用struts操作作为控制器。我也没有任何单例对象，但有一个类（名为HPOSG）其中我有很多静态方法，很可能同时被访问。这些方法不操纵任何数据，它们只是作为hibernate和业务类之间的桥梁。在整个应用程序中，每当我需要集合或其他东西时，我都会要求这些方法为我提供它们。

myInstance = (myInstanceClass) Session.merge(myInstance);