我正在从数据库创建实体类以将Hibernate集成到我的项目中，我使用从Eclipse Marketplace安装的Hibernate JBoss工具生成这些类，但是当我单击Finish生成类时，eclipse不会显示任何错误或消息，当我切换到“错误日志”选项卡时，我发现了类似的消息（见下文）。
org.hibernate.service.spi.ServiceException: Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]
at org.hibernate.service.internal.AbstractServiceRegistryImpl.createService(AbstractServiceRegistryImpl.java:270)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:232)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:209)
at org.hibernate.engine.jdbc.internal.JdbcServicesImpl.configure(JdbcServicesImpl.java:51)
at org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.configureService(StandardServiceRegistryImpl.java:94)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.initializeService(AbstractServiceRegistryImpl.java:241)
at org.hibernate.service.internal.AbstractServiceRegistryImpl.getService(AbstractServiceRegistryImpl.java:209)
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.handleTypes(MetadataBuildingProcess.java:356)
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:112)
at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.build(MetadataBuildingProcess.java:84)
at org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:470)
at org.hibernate.boot.internal.MetadataBuilderImpl.build(MetadataBuilderImpl.java:91)
at org.hibernate.boot.MetadataSources.buildMetadata(MetadataSources.java:183)
at org.jboss.tools.hibernate.runtime.v_5_3.internal.util.MetadataHelper.buildFromMetadataSources(MetadataHelper.java:49)
at org.jboss.tools.hibernate.runtime.v_5_3.internal.util.MetadataHelper.getMetadata(MetadataHelper.java:21)
at org.jboss.tools.hibernate.runtime.v_5_3.internal.ConfigurationFacadeImpl.getMetadata(ConfigurationFacadeImpl.java:174)
at org.jboss.tools.hibernate.runtime.v_5_3.internal.util.ConfigurationMetadataDescriptor.createMetadata(ConfigurationMetadataDescriptor.java:20)
at org.hibernate.tool.hbm2x.AbstractExporter.buildMetadata(AbstractExporter.java:207)
at org.hibernate.tool.hbm2x.AbstractExporter.getMetadata(AbstractExporter.java:57)
at org.hibernate.tool.hbm2x.AbstractExporter.setupContext(AbstractExporter.java:178)
at org.hibernate.tool.hbm2x.AbstractExporter.start(AbstractExporter.java:105)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.jboss.tools.hibernate.runtime.common.Util.invokeMethod(Util.java:43)
at org.jboss.tools.hibernate.runtime.common.AbstractExporterFacade.start(AbstractExporterFacade.java:72)
at org.hibernate.eclipse.console.wizards.NewConfigurationWizard.openContentStream(NewConfigurationWizard.java:301)
at org.hibernate.eclipse.console.wizards.NewConfigurationWizard.access$2(NewConfigurationWizard.java:295)
at org.hibernate.eclipse.console.wizards.NewConfigurationWizard$1.getInitialContents(NewConfigurationWizard.java:163)
at org.eclipse.ui.dialogs.WizardNewFileCreationPage.createNewFile(WizardNewFileCreationPage.java:380)
at org.hibernate.eclipse.console.wizards.NewConfigurationWizard.performFinish(NewConfigurationWizard.java:198)
at org.eclipse.jface.wizard.WizardDialog.finishPressed(WizardDialog.java:778)
at org.eclipse.jface.wizard.WizardDialog.buttonPressed(WizardDialog.java:417)
at org.eclipse.jface.dialogs.Dialog.lambda$0(Dialog.java:619)
at org.eclipse.swt.events.SelectionListener$1.widgetSelected(SelectionListener.java:81)
at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:249)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:86)
at org.eclipse.swt.widgets.Display.sendEvent(Display.java:5348)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1348)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4602)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:4183)
at org.eclipse.jface.window.Window.runEventLoop(Window.java:818)
at org.eclipse.jface.window.Window.open(Window.java:794)
at org.eclipse.ui.internal.handlers.WizardHandler$New.executeHandler(WizardHandler.java:269)
at org.eclipse.ui.internal.handlers.WizardHandler.execute(WizardHandler.java:290)
at org.eclipse.ui.internal.handlers.HandlerProxy.execute(HandlerProxy.java:291)
at org.eclipse.ui.internal.handlers.E4HandlerProxy.execute(E4HandlerProxy.java:92)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:55)
at org.eclipse.e4.core.internal.di.InjectorImpl.invokeUsingClass(InjectorImpl.java:305)
at org.eclipse.e4.core.internal.di.InjectorImpl.invoke(InjectorImpl.java:239)
at org.eclipse.e4.core.contexts.ContextInjectionFactory.invoke(ContextInjectionFactory.java:132)
at org.eclipse.e4.core.commands.internal.HandlerServiceHandler.execute(HandlerServiceHandler.java:152)
at org.eclipse.core.commands.Command.executeWithChecks(Command.java:494)
at org.eclipse.core.commands.ParameterizedCommand.executeWithChecks(ParameterizedCommand.java:487)
at org.eclipse.e4.core.commands.internal.HandlerServiceImpl.executeHandler(HandlerServiceImpl.java:210)
at org.eclipse.ui.internal.handlers.LegacyHandlerService.executeCommand(LegacyHandlerService.java:390)
at org.eclipse.ui.internal.actions.CommandAction.runWithEvent(CommandAction.java:151)
at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:565)
at org.eclipse.jface.action.ActionContributionItem.lambda$4(ActionContributionItem.java:397)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:86)
at org.eclipse.swt.widgets.Display.sendEvent(Display.java:5348)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1348)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4602)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:4183)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1150)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1039)
at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:153)
at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:680)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:594)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:148)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:151)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:388)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:243)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:653)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:590)
at org.eclipse.equinox.launcher.Main.run(Main.java:1499)
at org.eclipse.equinox.launcher.Main.main(Main.java:1472)
由以下原因引起：org.hibernate.HibernateException：如果未设置“ hibernate.dialect”，则对DialectResolutionInfo的访问不能为null 在org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.determineDialect（DialectFactoryImpl.java:100） 在org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl.buildDialect（DialectFactoryImpl.java:54） 在org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService（JdbcEnvironmentInitiator.java:137）上 在org.hibernate.engine.jdbc.env.internal.JdbcEnvironmentInitiator.initiateService（JdbcEnvironmentInitiator.java:35） 在org.hibernate.boot.registry.internal.StandardServiceRegistryImpl.initiateService（StandardServiceRegistryImpl.java:88） 在org.hibernate.service.internal.AbstractServiceRegistryImpl.createService（AbstractServiceRegistryImpl.java:258） ...还有90