Plug-in org.eclipse.wst.jsdt.ui was unable to load class org.eclipse.wst.jsdt.internal.ui.javaeditor

1、错误描述
org.eclipse.core.runtime.CoreException: Plug-in org.eclipse.wst.jsdt.ui was unable to load class org.eclipse.wst.jsdt.internal.ui.javaeditor.CompilationUnitEditor.
at org.eclipse.core.internal.registry.osgi.RegistryStrategyOSGI.throwException(RegistryStrategyOSGI.java:194)
at org.eclipse.core.internal.registry.osgi.RegistryStrategyOSGI.createExecutableExtension(RegistryStrategyOSGI.java:176)
at org.eclipse.core.internal.registry.ExtensionRegistry.createExecutableExtension(ExtensionRegistry.java:905)
at org.eclipse.core.internal.registry.ConfigurationElement.createExecutableExtension(ConfigurationElement.java:243)
at org.eclipse.core.internal.registry.ConfigurationElementHandle.createExecutableExtension(ConfigurationElementHandle.java:55)
at org.eclipse.ui.internal.WorkbenchPlugin$1.run(WorkbenchPlugin.java:291)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
at org.eclipse.ui.internal.WorkbenchPlugin.createExtension(WorkbenchPlugin.java:286)
at org.eclipse.ui.internal.registry.EditorDescriptor.createEditor(EditorDescriptor.java:235)
at org.eclipse.ui.internal.EditorReference.createPart(EditorReference.java:329)
at org.eclipse.ui.internal.e4.compatibility.CompatibilityPart.createPart(CompatibilityPart.java:278)
at org.eclipse.ui.internal.e4.compatibility.CompatibilityEditor.createPart(CompatibilityEditor.java:63)
at org.eclipse.ui.internal.e4.compatibility.CompatibilityPart.create(CompatibilityPart.java:316)
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.processAnnotated(InjectorImpl.java:966)
at org.eclipse.e4.core.internal.di.InjectorImpl.processAnnotated(InjectorImpl.java:931)
at org.eclipse.e4.core.internal.di.InjectorImpl.inject(InjectorImpl.java:151)
at org.eclipse.e4.core.internal.di.InjectorImpl.internalMake(InjectorImpl.java:375)
at org.eclipse.e4.core.internal.di.InjectorImpl.make(InjectorImpl.java:294)
at org.eclipse.e4.core.contexts.ContextInjectionFactory.make(ContextInjectionFactory.java:162)
at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.createFromBundle(ReflectionContributionFactory.java:105)
at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.doCreate(ReflectionContributionFactory.java:74)
at org.eclipse.e4.ui.internal.workbench.ReflectionContributionFactory.create(ReflectionContributionFactory.java:56)
at org.eclipse.e4.ui.workbench.renderers.swt.ContributedPartRenderer.createWidget(ContributedPartRenderer.java:129)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createWidget(PartRenderingEngine.java:975)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:651)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:757)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.access$0(PartRenderingEngine.java:728)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$2.run(PartRenderingEngine.java:722)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createGui(PartRenderingEngine.java:706)
at org.eclipse.e4.ui.internal.workbench.PartServiceImpl$1.handleEvent(PartServiceImpl.java:104)
at org.eclipse.e4.ui.services.internal.events.UIEventHandler$1.run(UIEventHandler.java:40)
at org.eclipse.swt.widgets.Synchronizer.syncExec(Synchronizer.java:233)
at org.eclipse.ui.internal.UISynchronizer.syncExec(UISynchronizer.java:145)
at org.eclipse.swt.widgets.Display.syncExec(Display.java:4821)
at org.eclipse.e4.ui.internal.workbench.swt.E4Application$1.syncExec(E4Application.java:211)
at org.eclipse.e4.ui.services.internal.events.UIEventHandler.handleEvent(UIEventHandler.java:36)
at org.eclipse.equinox.internal.event.EventHandlerWrapper.handleEvent(EventHandlerWrapper.java:201)
at org.eclipse.equinox.internal.event.EventHandlerTracker.dispatchEvent(EventHandlerTracker.java:197)
at org.eclipse.equinox.internal.event.EventHandlerTracker.dispatchEvent(EventHandlerTracker.java:1)
at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:230)
at org.eclipse.osgi.framework.eventmgr.ListenerQueue.dispatchEventSynchronous(ListenerQueue.java:148)
at org.eclipse.equinox.internal.event.EventAdminImpl.dispatchEvent(EventAdminImpl.java:135)
at org.eclipse.equinox.internal.event.EventAdminImpl.sendEvent(EventAdminImpl.java:78)
at org.eclipse.equinox.internal.event.EventComponent.sendEvent(EventComponent.java:39)
at org.eclipse.e4.ui.services.internal.events.EventBroker.send(EventBroker.java:94)
at org.eclipse.e4.ui.internal.workbench.UIEventPublisher.notifyChanged(UIEventPublisher.java:60)
at org.eclipse.emf.common.notify.impl.BasicNotifierImpl.eNotify(BasicNotifierImpl.java:374)
at org.eclipse.e4.ui.model.application.ui.impl.ElementContainerImpl.setSelectedElement(ElementContainerImpl.java:173)
at org.eclipse.e4.ui.internal.workbench.ModelServiceImpl.showElementInWindow(ModelServiceImpl.java:617)
at org.eclipse.e4.ui.internal.workbench.ModelServiceImpl.bringToTop(ModelServiceImpl.java:581)
at org.eclipse.e4.ui.internal.workbench.PartServiceImpl.delegateBringToTop(PartServiceImpl.java:770)
at org.eclipse.e4.ui.internal.workbench.PartServiceImpl.bringToTop(PartServiceImpl.java:401)
at org.eclipse.e4.ui.internal.workbench.PartServiceImpl.showPart(PartServiceImpl.java:1214)
at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditor(WorkbenchPage.java:3261)
at org.eclipse.ui.internal.WorkbenchPage.access$25(WorkbenchPage.java:3176)
at org.eclipse.ui.internal.WorkbenchPage$10.run(WorkbenchPage.java:3158)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:3153)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:3117)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:3107)
at org.eclipse.ui.ide.IDE.openEditor(IDE.java:563)
at org.eclipse.ui.ide.IDE.openEditor(IDE.java:518)
at org.eclipse.jdt.internal.ui.javaeditor.EditorUtility.openInEditor(EditorUtility.java:360)
at org.eclipse.jdt.internal.ui.javaeditor.EditorUtility.openInEditor(EditorUtility.java:167)
at org.eclipse.jdt.ui.actions.OpenAction.run(OpenAction.java:256)
at org.eclipse.jdt.ui.actions.OpenAction.run(OpenAction.java:221)
at org.eclipse.jdt.ui.actions.SelectionDispatchAction.dispatchRun(SelectionDispatchAction.java:271)
at org.eclipse.jdt.ui.actions.SelectionDispatchAction.run(SelectionDispatchAction.java:249)
at org.eclipse.jdt.internal.ui.navigator.OpenAndExpand.run(OpenAndExpand.java:50)
at org.eclipse.ui.actions.RetargetAction.run(RetargetAction.java:225)
at org.eclipse.ui.navigator.CommonNavigatorManager$2.open(CommonNavigatorManager.java:191)
at org.eclipse.ui.OpenAndLinkWithEditorHelper$InternalListener.open(OpenAndLinkWithEditorHelper.java:46)
at org.eclipse.jface.viewers.StructuredViewer$2.run(StructuredViewer.java:855)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:50)
at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:173)
at org.eclipse.jface.viewers.StructuredViewer.fireOpen(StructuredViewer.java:852)
at org.eclipse.jface.viewers.StructuredViewer.handleOpen(StructuredViewer.java:1169)
at org.eclipse.ui.navigator.CommonViewer.handleOpen(CommonViewer.java:451)
at org.eclipse.jface.util.OpenStrategy.fireOpenEvent(OpenStrategy.java:278)
at org.eclipse.jface.util.OpenStrategy.access$2(OpenStrategy.java:272)
at org.eclipse.jface.util.OpenStrategy$1.handleEvent(OpenStrategy.java:313)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4418)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1079)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4236)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3824)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$4.run(PartRenderingEngine.java:1121)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1022)
at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:150)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:693)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:610)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:148)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:138)
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:673)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:610)
at org.eclipse.equinox.launcher.Main.run(Main.java:1519)
Caused by: java.lang.ClassNotFoundException: An error occurred while automatically activating bundle org.eclipse.wst.jsdt.ui (866).
at org.eclipse.osgi.internal.hooks.EclipseLazyStarter.postFindLocalClass(EclipseLazyStarter.java:116)
at org.eclipse.osgi.internal.loader.classpath.ClasspathManager.findLocalClass(ClasspathManager.java:529)
at org.eclipse.osgi.internal.loader.ModuleClassLoader.findLocalClass(ModuleClassLoader.java:325)
at org.eclipse.osgi.internal.loader.BundleLoader.findLocalClass(BundleLoader.java:345)
at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:423)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:372)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:364)
at org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(ModuleClassLoader.java:161)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at org.eclipse.osgi.internal.framework.EquinoxBundle.loadClass(EquinoxBundle.java:564)
at org.eclipse.core.internal.registry.osgi.RegistryStrategyOSGI.createExecutableExtension(RegistryStrategyOSGI.java:174)
at org.eclipse.core.internal.registry.ExtensionRegistry.createExecutableExtension(ExtensionRegistry.java:905)
at org.eclipse.core.internal.registry.ConfigurationElement.createExecutableExtension(ConfigurationElement.java:243)
at org.eclipse.core.internal.registry.ConfigurationElementHandle.createExecutableExtension(ConfigurationElementHandle.java:55)
at org.eclipse.core.internal.filebuffers.ExtensionsRegistry.getExtension(ExtensionsRegistry.java:224)
at org.eclipse.core.internal.filebuffers.ExtensionsRegistry.doGetDocumentSetupParticipants(ExtensionsRegistry.java:352)
at org.eclipse.core.internal.filebuffers.ExtensionsRegistry.getDocumentSetupParticipants(ExtensionsRegistry.java:369)
at org.eclipse.core.internal.filebuffers.ResourceExtensionRegistry.getDocumentSetupParticipants(ResourceExtensionRegistry.java:121)
at org.eclipse.core.internal.filebuffers.ResourceTextFileBufferManager.createEmptyDocument(ResourceTextFileBufferManager.java:138)
at org.eclipse.core.internal.filebuffers.ResourceTextFileBuffer.initializeFileBufferContent(ResourceTextFileBuffer.java:264)
at org.eclipse.core.internal.filebuffers.ResourceFileBuffer.create(ResourceFileBuffer.java:248)
at org.eclipse.core.internal.filebuffers.TextFileBufferManager.connect(TextFileBufferManager.java:112)
at org.eclipse.wst.sse.core.internal.FileBufferModelManager.getModel(FileBufferModelManager.java:786)
at org.eclipse.wst.sse.core.internal.model.ModelManagerImpl._doCommonGetModel(ModelManagerImpl.java:548)
at org.eclipse.wst.sse.core.internal.model.ModelManagerImpl._commonGetModel(ModelManagerImpl.java:512)
at org.eclipse.wst.sse.core.internal.model.ModelManagerImpl._commonGetModel(ModelManagerImpl.java:485)
at org.eclipse.wst.sse.core.internal.model.ModelManagerImpl.getModelForRead(ModelManagerImpl.java:1443)
at org.eclipse.wst.sse.core.internal.validate.ValidatorGroupListener.validationStarting(ValidatorGroupListener.java:91)
at org.eclipse.wst.validation.internal.ValManager$2.run(ValManager.java:854)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.wst.validation.internal.ValManager.notifyGroupListenersStarting(ValManager.java:852)
at org.eclipse.wst.validation.internal.ValManager.accept(ValManager.java:807)
at org.eclipse.wst.validation.internal.ValManager.validate(ValManager.java:669)
at org.eclipse.wst.validation.internal.ValBuilderJob$Visitor.visit(ValBuilderJob.java:327)
at org.eclipse.core.internal.events.ResourceDelta.accept(ResourceDelta.java:64)
at org.eclipse.core.internal.events.ResourceDelta.accept(ResourceDelta.java:75)
at org.eclipse.core.internal.events.ResourceDelta.accept(ResourceDelta.java:75)
at org.eclipse.core.internal.events.ResourceDelta.accept(ResourceDelta.java:75)
at org.eclipse.core.internal.events.ResourceDelta.accept(ResourceDelta.java:75)
at org.eclipse.core.internal.events.ResourceDelta.accept(ResourceDelta.java:75)
at org.eclipse.core.internal.events.ResourceDelta.accept(ResourceDelta.java:75)
at org.eclipse.core.internal.events.ResourceDelta.accept(ResourceDelta.java:75)
at org.eclipse.core.internal.events.ResourceDelta.accept(ResourceDelta.java:48)
at org.eclipse.wst.validation.internal.ValBuilderJob.deltaBuild(ValBuilderJob.java:211)
at org.eclipse.wst.validation.internal.ValBuilderJob.run(ValBuilderJob.java:179)
at org.eclipse.wst.validation.internal.ValBuilderJob.runInWorkspace(ValBuilderJob.java:126)
at org.eclipse.core.internal.resources.InternalWorkspaceJob.run(InternalWorkspaceJob.java:39)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)
Caused by: org.osgi.framework.BundleException: Exception in org.eclipse.wst.jsdt.internal.ui.JavaScriptPlugin.start() of bundle org.eclipse.wst.jsdt.ui.
at org.eclipse.osgi.internal.framework.BundleContextImpl.startActivator(BundleContextImpl.java:795)
at org.eclipse.osgi.internal.framework.BundleContextImpl.start(BundleContextImpl.java:724)
at org.eclipse.osgi.internal.framework.EquinoxBundle.startWorker0(EquinoxBundle.java:932)
at org.eclipse.osgi.internal.framework.EquinoxBundle$EquinoxModule.startWorker(EquinoxBundle.java:309)
at org.eclipse.osgi.container.Module.doStart(Module.java:581)
at org.eclipse.osgi.container.Module.start(Module.java:449)
at org.eclipse.osgi.framework.util.SecureAction.start(SecureAction.java:470)
at org.eclipse.osgi.internal.hooks.EclipseLazyStarter.postFindLocalClass(EclipseLazyStarter.java:107)
... 47 more
Caused by: org.eclipse.swt.SWTException: Invalid thread access
at org.eclipse.swt.SWT.error(SWT.java:4533)
at org.eclipse.swt.SWT.error(SWT.java:4448)
at org.eclipse.swt.SWT.error(SWT.java:4419)
at org.eclipse.jface.resource.FontRegistry.calculateDefaultFont(FontRegistry.java:516)
at org.eclipse.jface.resource.FontRegistry.defaultFontRecord(FontRegistry.java:560)
at org.eclipse.jface.resource.FontRegistry.defaultFontData(FontRegistry.java:573)
at org.eclipse.jface.resource.FontRegistry.getFontData(FontRegistry.java:589)
at org.eclipse.wst.jsdt.internal.ui.JavaScriptPlugin.ensurePreferenceStoreBackwardsCompatibility(JavaScriptPlugin.java:405)
at org.eclipse.wst.jsdt.internal.ui.JavaScriptPlugin.start(JavaScriptPlugin.java:336)
at org.eclipse.osgi.internal.framework.BundleContextImpl$3.run(BundleContextImpl.java:774)
at org.eclipse.osgi.internal.framework.BundleContextImpl$3.run(BundleContextImpl.java:1)
at java.security.AccessController.doPrivileged(Native Method)
at org.eclipse.osgi.internal.framework.BundleContextImpl.startActivator(BundleContextImpl.java:767)
... 54 more

Plug-in org.eclipse.wst.jsdt.ui was unable to load class org.eclipse.wst.jsdt.internal.ui.javaeditor
2、错误原因
     eclipse一直在加载校验中，关闭eclipse后再次打开，无法打开JavaScript文件；提示上述错误。
     由错误提示可知，是eclipse中的编译器类加载失败

3、解决办法
（1）最直接的办法
        删除eclipse工作空间的.metadata文件夹
（2）切换工作空间