Hibernate 仅在GWT托管模式下休眠ClassCastException_Hibernate_Gwt_Maven_Jetty_Classcastexception

Hibernate 仅在GWT托管模式下休眠ClassCastException

hibernate gwt maven jetty

Hibernate 仅在GWT托管模式下休眠ClassCastException,hibernate,gwt,maven,jetty,classcastexception,Hibernate,Gwt,Maven,Jetty,Classcastexception,您好，感谢收看；-）我们的问题/错误是： javax.persistence.PersistenceException: [PersistenceUnit: PUname] Unable to build EntityManagerFactory ... Caused by: org.hibernate.HibernateException: Could not instantiate dialect class ... Caused by: java.lang.ClassCastExcept

您好，感谢收看；-）

我们的问题/错误是：

javax.persistence.PersistenceException: [PersistenceUnit: PUname] Unable to build EntityManagerFactory
...
Caused by: org.hibernate.HibernateException: Could not instantiate dialect class
...
Caused by: java.lang.ClassCastException: org.hibernate.dialect.MySQLDialect cannot be cast to org.hibernate.dialect.Dialect
...

（请参见底部的完整堆栈跟踪）

它发生在使用以下技术的基于GWT的web应用程序中：

马文
Hibernate EntityManager/JPA
圭斯
GWT
GWT-P
GWTMaven插件

需要强调的事实是，它在Tomcat中确实有效。只有在开发模式aka-hosted模式下（使用Jetty），使用GWT-Maven插件（目标为GWT:run），我们才能得到ClassCastException。我们在玩Hibernate依赖关系时运气不佳（添加了

Hibernate验证器

和/或

Hibernate-jpa-2.0-api

）。 ClassCastException是在JPA启动时在实际使用任何服务之前抛出的。顺便说一句：JPA是使用GUI设置的：

    install(new JpaPersistModule("PUname"));
    filter("/*").through(PersistFilter.class);

值得一提的是，禁用方言设置（在persistence.xml中）也会在JPA启动时创建另一个ClassCastException：

javax.persistence.PersistenceException: [PersistenceUnit: dsmgmt] Unable to build EntityManagerFactory
...
Caused by: org.hibernate.HibernateException: Unable to instantiate specified TransactionFactory class  [org.hibernate.engine.transaction.internal.jdbc.JdbcTransactionFactory]
...
Caused by: java.lang.ClassCastException: org.hibernate.engine.transaction.internal.jdbc.JdbcTransactionFactory cannot be cast to org.hibernate.engine.transaction.spi.TransactionFactory
...

为什么它会在码头上断裂？是什么原因造成的，或者如何修复

文件：META-INF/persistence.xml

 <persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="1.0" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">
    <persistence-unit name="PUname" transaction-type="RESOURCE_LOCAL">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <class>our.test.class</class>
        <properties>
            <property name="hibernate.connection.username" value="user"/>
            <property name="hibernate.connection.password" value="pass"/>
            <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
            <property name="hibernate.connection.url" value="jdbc:mysql://machine:3306/db"/>
            <property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/>
            <property name="hibernate.hbm2ddl.auto" value="update"/>
        </properties>
    </persistence-unit>
 </persistence>

完整堆栈跟踪：

javax.persistence.PersistenceException: [PersistenceUnit: PUname] Unable to build EntityManagerFactory
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:916)
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:887)
    at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:56)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:63)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:47)
    at com.google.inject.persist.jpa.JpaPersistService.start(JpaPersistService.java:94)
    at com.google.inject.persist.PersistFilter.init(PersistFilter.java:77)
    at com.google.inject.servlet.FilterDefinition.init(FilterDefinition.java:114)
    at com.google.inject.servlet.ManagedFilterPipeline.initPipeline(ManagedFilterPipeline.java:98)
    at com.google.inject.servlet.GuiceFilter.init(GuiceFilter.java:172)
    at org.mortbay.jetty.servlet.FilterHolder.doStart(FilterHolder.java:97)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:593)
    at org.mortbay.jetty.servlet.Context.startContext(Context.java:140)
    at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220)
    at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:513)
    at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448)
    at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload.doStart(JettyLauncher.java:468)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.handler.RequestLogHandler.doStart(RequestLogHandler.java:115)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.Server.doStart(Server.java:222)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672)
    at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
    at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1068)
    at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:811)
    at com.google.gwt.dev.DevMode.main(DevMode.java:311)
 Caused by: org.hibernate.HibernateException: Could not instantiate dialect class
    at org.hibernate.service.jdbc.dialect.internal.DialectFactoryImpl.constructDialect(DialectFactoryImpl.java:82)
    at org.hibernate.service.jdbc.dialect.internal.DialectFactoryImpl.buildDialect(DialectFactoryImpl.java:64)
    at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:142)
    at org.hibernate.service.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:81)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:160)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:133)
    at org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:71)
    at org.hibernate.cfg.Configuration.buildSettingsInternal(Configuration.java:2259)
    at org.hibernate.cfg.Configuration.buildSettings(Configuration.java:2255)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1724)
    at org.hibernate.ejb.EntityManagerFactoryImpl.<init>(EntityManagerFactoryImpl.java:76)
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:907)
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:887)
    at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:56)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:63)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:47)
    at com.google.inject.persist.jpa.JpaPersistService.start(JpaPersistService.java:94)
    at com.google.inject.persist.PersistFilter.init(PersistFilter.java:77)
    at com.google.inject.servlet.FilterDefinition.init(FilterDefinition.java:114)
    at com.google.inject.servlet.ManagedFilterPipeline.initPipeline(ManagedFilterPipeline.java:98)
    at com.google.inject.servlet.GuiceFilter.init(GuiceFilter.java:172)
    at org.mortbay.jetty.servlet.FilterHolder.doStart(FilterHolder.java:97)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:593)
    at org.mortbay.jetty.servlet.Context.startContext(Context.java:140)
    at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220)
    at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:513)
    at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448)
    at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload.doStart(JettyLauncher.java:468)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.handler.RequestLogHandler.doStart(RequestLogHandler.java:115)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.Server.doStart(Server.java:222)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672)
    at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
    at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1068)
    at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:811)
    at com.google.gwt.dev.DevMode.main(DevMode.java:311)
 Caused by: java.lang.ClassCastException: org.hibernate.dialect.MySQLDialect cannot be cast to org.hibernate.dialect.Dialect
    at org.hibernate.service.jdbc.dialect.internal.DialectFactoryImpl.constructDialect(DialectFactoryImpl.java:73)
    at org.hibernate.service.jdbc.dialect.internal.DialectFactoryImpl.buildDialect(DialectFactoryImpl.java:64)
    at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:142)
    at org.hibernate.service.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:81)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:160)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:133)
    at org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:71)
    at org.hibernate.cfg.Configuration.buildSettingsInternal(Configuration.java:2259)
    at org.hibernate.cfg.Configuration.buildSettings(Configuration.java:2255)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1724)
    at org.hibernate.ejb.EntityManagerFactoryImpl.<init>(EntityManagerFactoryImpl.java:76)
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:907)
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:887)
    at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:56)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:63)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:47)
    at com.google.inject.persist.jpa.JpaPersistService.start(JpaPersistService.java:94)
    at com.google.inject.persist.PersistFilter.init(PersistFilter.java:77)
    at com.google.inject.servlet.FilterDefinition.init(FilterDefinition.java:114)
    at com.google.inject.servlet.ManagedFilterPipeline.initPipeline(ManagedFilterPipeline.java:98)
    at com.google.inject.servlet.GuiceFilter.init(GuiceFilter.java:172)
    at org.mortbay.jetty.servlet.FilterHolder.doStart(FilterHolder.java:97)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:593)
    at org.mortbay.jetty.servlet.Context.startContext(Context.java:140)
    at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220)
    at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:513)
    at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448)
    at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload.doStart(JettyLauncher.java:468)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.handler.RequestLogHandler.doStart(RequestLogHandler.java:115)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.Server.doStart(Server.java:222)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672)
    at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
    at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1068)
    at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:811)
    at com.google.gwt.dev.DevMode.main(DevMode.java:311)

javax.persistence.PersistenceException:[PersistenceUnit:PUname]无法构建EntityManagerFactory
位于org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory（Ejb3Configuration.java:916）
位于org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory（Ejb3Configuration.java:887）
位于org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory（HibernatePersistence.java:56）
位于javax.persistence.persistence.createEntityManagerFactory（persistence.java:63）
位于javax.persistence.persistence.createEntityManagerFactory（persistence.java:47）
位于com.google.inject.persist.jpa.JpaPersistService.start（JpaPersistService.java:94）
位于com.google.inject.persist.PersistFilter.init（PersistFilter.java:77）
位于com.google.inject.servlet.FilterDefinition.init（FilterDefinition.java:114）
位于com.google.inject.servlet.ManagedFilterPipeline.initPipeline（ManagedFilterPipeline.java:98）
位于com.google.inject.servlet.GuiceFilter.init（GuiceFilter.java:172）
位于org.mortbay.jetty.servlet.FilterHolder.doStart（FilterHolder.java:97）
位于org.mortbay.component.AbstractLifeCycle.start（AbstractLifeCycle.java:39）
位于org.mortbay.jetty.servlet.ServletHandler.initialize（ServletHandler.java:593）
位于org.mortbay.jetty.servlet.Context.startContext（Context.java:140）
位于org.mortbay.jetty.webapp.WebAppContext.startContext（WebAppContext.java:1220）
位于org.mortbay.jetty.handler.ContextHandler.doStart（ContextHandler.java:513）
位于org.mortbay.jetty.webapp.WebAppContext.doStart（WebAppContext.java:448）
在com.google.gwt.dev.shell.jetty.jettylancher$WebAppContextWithReload.doStart（jettylancher.java:468）
位于org.mortbay.component.AbstractLifeCycle.start（AbstractLifeCycle.java:39）
位于org.mortbay.jetty.handler.HandlerWrapper.doStart（HandlerWrapper.java:130）
位于org.mortbay.jetty.handler.RequestLogHandler.doStart（RequestLogHandler.java:115）
位于org.mortbay.component.AbstractLifeCycle.start（AbstractLifeCycle.java:39）
位于org.mortbay.jetty.handler.HandlerWrapper.doStart（HandlerWrapper.java:130）
位于org.mortbay.jetty.Server.doStart（Server.java:222）
位于org.mortbay.component.AbstractLifeCycle.start（AbstractLifeCycle.java:39）
在com.google.gwt.dev.shell.jetty.jettylancher.start（jettylancher.java:672）
位于com.google.gwt.dev.DevMode.doStartUpServer（DevMode.java:509）
位于com.google.gwt.dev.DevModeBase.startUp（DevModeBase.java:1068）
位于com.google.gwt.dev.DevModeBase.run（DevModeBase.java:811）
位于com.google.gwt.dev.DevMode.main（DevMode.java:311）
原因：org.hibernate.HibernateException:无法实例化方言类
位于org.hibernate.service.jdbc.dialogue.internal.dialogueFactoryImpl.ConstructDialogue（dialogueFactoryImpl.java:82）
位于org.hibernate.service.jdbc.dialogue.internal.dialogueFactoryImpl.buildDialogue（dialogueFactoryImpl.java:64）
位于org.hibernate.engine.jdbc.internal.jdbcservicesiml.configure（jdbcservicesiml.java:142）
位于org.hibernate.service.internal.StandardServiceRegistryImpl.configureService（StandardServiceRegistryImpl.java:81）
位于org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService（AbstractServiceRegistryImpl.java:160）
位于org.hibernate.service.internal.AbstractServiceRegistryImpl.getService（AbstractServiceRegistryImpl.java:133）
在org.hibernate.cfg.SettingsFactory.buildSettings（SettingsFactory.java:71）上
位于org.hibernate.cfg.Configuration.buildSettingsInternal（Configuration.java:2259）
位于org.hibernate.cfg.Configuration.buildSettings（Configuration.java:2255）
位于org.hibernate.cfg.Configuration.buildSessionFactory（Configuration.java:1724）
位于org.hibernate.ejb.EntityManagerFactoryImpl。（EntityManagerFactoryImpl.java:76）
位于org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory（Ejb3Configuration.java:907）
位于org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory（Ejb3Configuration.java:887）
位于org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory（HibernatePersistence.java:56）
位于javax.persistence.persistence.createEntityManagerFactory（persistence.java:63）
位于javax.persistence.persistence.createEntityManagerFactory（persistence.java:47）
位于com.google.inject.persist.jpa.JpaPersistService.start（JpaPersistService.java:94）
位于com.google.inject.persist.PersistFilter.init（PersistFilter.java:77）
位于com.google.inject.servlet.FilterDefinition.init（FilterDefinition.java:114）
位于com.google.inject.servlet.ManagedFilterPipeline.initPipeline（ManagedFilterPipeline.java:98）
位于com.google.inject.servlet.GuiceFilter.init（GuiceFilter.java:172）
位于org.mortbay.jetty.servlet.FilterHolder.doStart（FilterHolder.java:97）
位于org.mortbay.component.AbstractLifeCycle.start（AbstractLifeCycle.java:39）
位于org.mortbay.jetty.servlet.ServletHandler.initialize（ServletHandler.java:593）
在org.mortbay.j
javax.persistence.PersistenceException: [PersistenceUnit: PUname] Unable to build EntityManagerFactory
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:916)
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:887)
    at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:56)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:63)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:47)
    at com.google.inject.persist.jpa.JpaPersistService.start(JpaPersistService.java:94)
    at com.google.inject.persist.PersistFilter.init(PersistFilter.java:77)
    at com.google.inject.servlet.FilterDefinition.init(FilterDefinition.java:114)
    at com.google.inject.servlet.ManagedFilterPipeline.initPipeline(ManagedFilterPipeline.java:98)
    at com.google.inject.servlet.GuiceFilter.init(GuiceFilter.java:172)
    at org.mortbay.jetty.servlet.FilterHolder.doStart(FilterHolder.java:97)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:593)
    at org.mortbay.jetty.servlet.Context.startContext(Context.java:140)
    at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220)
    at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:513)
    at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448)
    at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload.doStart(JettyLauncher.java:468)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.handler.RequestLogHandler.doStart(RequestLogHandler.java:115)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.Server.doStart(Server.java:222)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672)
    at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
    at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1068)
    at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:811)
    at com.google.gwt.dev.DevMode.main(DevMode.java:311)
 Caused by: org.hibernate.HibernateException: Could not instantiate dialect class
    at org.hibernate.service.jdbc.dialect.internal.DialectFactoryImpl.constructDialect(DialectFactoryImpl.java:82)
    at org.hibernate.service.jdbc.dialect.internal.DialectFactoryImpl.buildDialect(DialectFactoryImpl.java:64)
    at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:142)
    at org.hibernate.service.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:81)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:160)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:133)
    at org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:71)
    at org.hibernate.cfg.Configuration.buildSettingsInternal(Configuration.java:2259)
    at org.hibernate.cfg.Configuration.buildSettings(Configuration.java:2255)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1724)
    at org.hibernate.ejb.EntityManagerFactoryImpl.<init>(EntityManagerFactoryImpl.java:76)
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:907)
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:887)
    at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:56)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:63)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:47)
    at com.google.inject.persist.jpa.JpaPersistService.start(JpaPersistService.java:94)
    at com.google.inject.persist.PersistFilter.init(PersistFilter.java:77)
    at com.google.inject.servlet.FilterDefinition.init(FilterDefinition.java:114)
    at com.google.inject.servlet.ManagedFilterPipeline.initPipeline(ManagedFilterPipeline.java:98)
    at com.google.inject.servlet.GuiceFilter.init(GuiceFilter.java:172)
    at org.mortbay.jetty.servlet.FilterHolder.doStart(FilterHolder.java:97)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:593)
    at org.mortbay.jetty.servlet.Context.startContext(Context.java:140)
    at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220)
    at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:513)
    at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448)
    at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload.doStart(JettyLauncher.java:468)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.handler.RequestLogHandler.doStart(RequestLogHandler.java:115)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.Server.doStart(Server.java:222)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672)
    at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
    at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1068)
    at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:811)
    at com.google.gwt.dev.DevMode.main(DevMode.java:311)
 Caused by: java.lang.ClassCastException: org.hibernate.dialect.MySQLDialect cannot be cast to org.hibernate.dialect.Dialect
    at org.hibernate.service.jdbc.dialect.internal.DialectFactoryImpl.constructDialect(DialectFactoryImpl.java:73)
    at org.hibernate.service.jdbc.dialect.internal.DialectFactoryImpl.buildDialect(DialectFactoryImpl.java:64)
    at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:142)
    at org.hibernate.service.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:81)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:160)
    at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:133)
    at org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:71)
    at org.hibernate.cfg.Configuration.buildSettingsInternal(Configuration.java:2259)
    at org.hibernate.cfg.Configuration.buildSettings(Configuration.java:2255)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1724)
    at org.hibernate.ejb.EntityManagerFactoryImpl.<init>(EntityManagerFactoryImpl.java:76)
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:907)
    at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:887)
    at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:56)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:63)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:47)
    at com.google.inject.persist.jpa.JpaPersistService.start(JpaPersistService.java:94)
    at com.google.inject.persist.PersistFilter.init(PersistFilter.java:77)
    at com.google.inject.servlet.FilterDefinition.init(FilterDefinition.java:114)
    at com.google.inject.servlet.ManagedFilterPipeline.initPipeline(ManagedFilterPipeline.java:98)
    at com.google.inject.servlet.GuiceFilter.init(GuiceFilter.java:172)
    at org.mortbay.jetty.servlet.FilterHolder.doStart(FilterHolder.java:97)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:593)
    at org.mortbay.jetty.servlet.Context.startContext(Context.java:140)
    at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220)
    at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:513)
    at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448)
    at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload.doStart(JettyLauncher.java:468)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.handler.RequestLogHandler.doStart(RequestLogHandler.java:115)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.Server.doStart(Server.java:222)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672)
    at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
    at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1068)
    at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:811)
    at com.google.gwt.dev.DevMode.main(DevMode.java:311)