could not instantiate id generator的错误

Question

项目在启动的时候错误提示：
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in class path resource [applicationContext.xml]: Invocation of init method failed; nested exception is org.hibernate.MappingException: could not instantiate id generator
Caused by: 
org.hibernate.MappingException: could not instantiate id generator
at org.hibernate.id.IdentifierGeneratorFactory.create(IdentifierGeneratorFactory.java:92)
at org.hibernate.mapping.SimpleValue.createIdentifierGenerator(SimpleValue.java:151)
at org.hibernate.impl.SessionFactoryImpl.<init>(SessionFactoryImpl.java:178)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1005)
at org.springframework.orm.hibernate3.LocalSessionFactoryBean.newSessionFactory(LocalSessionFactoryBean.java:805)
at org.springframework.orm.hibernate3.LocalSessionFactoryBean.buildSessionFactory(LocalSessionFactoryBean.java:745)
at org.springframework.orm.hibernate3.AbstractSessionFactoryBean.afterPropertiesSet(AbstractSessionFactoryBean.java:134)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1203)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1172)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:427)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:249)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:155)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:246)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:160)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:285)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:352)
at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:246)
at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:189)
at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:49)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3795)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4252)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:760)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:740)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:544)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:927)
at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:890)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:492)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1150)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:120)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1022)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:736)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1014)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
at org.apache.catalina.core.StandardService.start(StandardService.java:448)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:700)
at org.apache.catalina.startup.Catalina.start(Catalina.java:552)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:295)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:433)
Caused by: org.hibernate.MappingException: Dialect does not support sequences
at org.hibernate.dialect.Dialect.getSequenceNextValString(Dialect.java:430)
at org.hibernate.id.SequenceGenerator.configure(SequenceGenerator.java:65)
at org.hibernate.id.IdentifierGeneratorFactory.create(IdentifierGeneratorFactory.java:88)
... 42 more
项目基本情况：
用hibernate和Spring连接SQLServer数据库。
本来这个项目是连接的ORACLE数据库，现在改成SQLServer，我把主键的生成策略也都改成indetify了，为什么还是有“Caused by: org.hibernate.MappingException: Dialect does not support sequences”这个错误？
我如果把项目中hibernate.cfg.xml中映射元素删除的话，项目就正常启动不报错。就是删了<mapping resource="com/hsg/pojos/Treemenu.hbm.xml"/> 这些东西，项目能正常启动。
generatorsqlserversshhibernatespring

Answer 1

Treemenu这个表的id是否设置自动增长了？我是说数据库里

Answer 2

could not instantiate id generator　　ｈｉｂｅｒｎａｔｅ映射错误　　楼主你仔细检查下

Answer 3

<mapping resource="com/hsg/pojos/Treemenu.hbm.xml"/> 这些东西，项目能正常启动。　看看这个问题里面的一些映射　是否跟数据里面字段的设置不同

Answer 4

貌似没有。我尝试一下试试。。但是我在hibernate的配置文件中的mapping映射只映射了一个测试类，不带自增的。还是会包上面的错误。