'java.lang.AssertionError: assertion failed' Error while starting Scala-IDE(Eclipse)

Question

I am new to eclipse. Please excuse me if I am wrong about something.

I've downloaded Scala IDE for eclipse 4.6.1. I've extracted the contents and tried to launch eclipse. Initially there was a problem with maven: 'Failed to read artifact descriptor for maven-resources-plugin'. I was able to solve this error(I assume so because it didn't show up again) by adding the proxy settings to settings.xml in .m2 folder.

Now I get a new error saying: 'java.lang.AssertionError: assertion failed'

Below is the full error:

!ENTRY org.eclipse.e4.ui.workbench.swt 4 2 2017-07-10 14:34:58.379
!MESSAGE Problems occurred when invoking code from plug-in: "org.eclipse.e4.ui.workbench.swt".
!STACK 0
java.lang.AssertionError: assertion failed
    at scala.Predef$.assert(Predef.scala:204)
    at scala.tools.scalap.Classfile.<init>(Classfile.scala:17)
    at org.scalaide.core.internal.jdt.model.ScalaClassFileDescriber$.isScala(ScalaClassFileDescriber.scala:16)
    at org.scalaide.core.internal.jdt.model.ScalaClassFileDescriber.describe(ScalaClassFileDescriber.scala:38)
    at org.eclipse.core.internal.content.ContentTypeCatalog.describe(ContentTypeCatalog.java:229)
    at org.eclipse.core.internal.content.ContentTypeCatalog.collectMatchingByContents(ContentTypeCatalog.java:201)
    at org.eclipse.core.internal.content.ContentTypeCatalog.internalFindContentTypesFor(ContentTypeCatalog.java:412)
    at org.eclipse.core.internal.content.ContentTypeCatalog.internalFindContentTypesFor(ContentTypeCatalog.java:461)
    at org.eclipse.core.internal.content.ContentTypeCatalog.findContentTypesFor(ContentTypeCatalog.java:309)
    at org.eclipse.core.internal.content.ContentTypeMatcher.findContentTypeFor(ContentTypeMatcher.java:36)
    at org.eclipse.wst.sse.core.internal.modelhandler.ModelHandlerRegistry.getHandlerFor(ModelHandlerRegistry.java:230)
    at org.eclipse.wst.sse.core.internal.model.ModelManagerImpl.calculateType(ModelManagerImpl.java:750)
    at org.eclipse.wst.sse.core.internal.model.ModelManagerImpl.getModelForEdit(ModelManagerImpl.java:1427)
    at org.eclipse.wst.sse.ui.internal.StorageModelProvider.loadModel(StorageModelProvider.java:733)
    at org.eclipse.wst.sse.ui.internal.StorageModelProvider.loadModel(StorageModelProvider.java:705)
    at org.eclipse.wst.sse.ui.internal.StorageModelProvider.selfCreateModel(StorageModelProvider.java:761)
    at org.eclipse.wst.sse.ui.internal.StorageModelProvider.createModelInfo(StorageModelProvider.java:478)
    at org.eclipse.wst.sse.ui.internal.StorageModelProvider.createElementInfo(StorageModelProvider.java:469)
    at org.eclipse.ui.texteditor.AbstractDocumentProvider.connect(AbstractDocumentProvider.java:392)
    at org.eclipse.ui.texteditor.AbstractTextEditor.doSetInput(AbstractTextEditor.java:4178)
    at org.eclipse.ui.texteditor.StatusTextEditor.doSetInput(StatusTextEditor.java:229)
    at org.eclipse.ui.texteditor.AbstractDecoratedTextEditor.doSetInput(AbstractDecoratedTextEditor.java:1466)
    at org.eclipse.ui.editors.text.TextEditor.doSetInput(TextEditor.java:150)
    at org.eclipse.wst.sse.ui.StructuredTextEditor.doSetInput(StructuredTextEditor.java:1958)
    at org.eclipse.ui.texteditor.AbstractTextEditor$5.run(AbstractTextEditor.java:3154)
    at org.eclipse.ui.internal.WorkbenchWindow.run(WorkbenchWindow.java:2126)
    at org.eclipse.ui.texteditor.AbstractTextEditor.internalInit(AbstractTextEditor.java:3172)
    at org.eclipse.ui.texteditor.AbstractTextEditor.init(AbstractTextEditor.java:3197)
    at org.eclipse.wst.sse.ui.StructuredTextEditor.init(StructuredTextEditor.java:2651)
    at org.eclipse.ui.part.MultiPageEditorPart.addPage(MultiPageEditorPart.java:240)
    at org.eclipse.ui.forms.editor.FormEditor.addPage(FormEditor.java:330)
    at org.eclipse.ui.part.MultiPageEditorPart.addPage(MultiPageEditorPart.java:214)
    at org.eclipse.ui.forms.editor.FormEditor.addPage(FormEditor.java:312)
    at org.eclipse.m2e.editor.pom.MavenPomEditor.addSourcePage(MavenPomEditor.java:618)
    at org.eclipse.m2e.editor.pom.MavenPomEditor.addPages(MavenPomEditor.java:356)
    at org.eclipse.ui.forms.editor.FormEditor.createPages(FormEditor.java:140)
    at org.eclipse.ui.part.MultiPageEditorPart.createPartControl(MultiPageEditorPart.java:363)
    at org.eclipse.ui.internal.e4.compatibility.CompatibilityPart.createPartControl(CompatibilityPart.java:150)
    at org.eclipse.ui.internal.e4.compatibility.CompatibilityEditor.createPartControl(CompatibilityEditor.java:99)
    at org.eclipse.ui.internal.e4.compatibility.CompatibilityPart.create(CompatibilityPart.java:340)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    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.workbench.renderers.swt.StackRenderer.showTab(StackRenderer.java:1324)
    at org.eclipse.e4.ui.workbench.renderers.swt.LazyStackRenderer.postProcess(LazyStackRenderer.java:103)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:669)
    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.workbench.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:70)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:665)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$1.run(PartRenderingEngine.java:536)
    at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.createGui(PartRenderingEngine.java:520)
    at org.eclipse.e4.ui.workbench.renderers.swt.ElementReferenceRenderer.createWidget(ElementReferenceRenderer.java:70)
    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.workbench.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:70)
    at org.eclipse.e4.ui.workbench.renderers.swt.SashRenderer.processContents(SashRenderer.java:142)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:665)
    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.workbench.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:70)
    at org.eclipse.e4.ui.workbench.renderers.swt.SashRenderer.processContents(SashRenderer.java:142)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:665)
    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.workbench.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:70)
    at org.eclipse.e4.ui.workbench.renderers.swt.SashRenderer.processContents(SashRenderer.java:142)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:665)
    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.workbench.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:70)
    at org.eclipse.e4.ui.workbench.renderers.swt.PerspectiveRenderer.processContents(PerspectiveRenderer.java:49)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:665)
    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.workbench.renderers.swt.PerspectiveStackRenderer.showTab(PerspectiveStackRenderer.java:82)
    at org.eclipse.e4.ui.workbench.renderers.swt.LazyStackRenderer.postProcess(LazyStackRenderer.java:103)
    at org.eclipse.e4.ui.workbench.renderers.swt.PerspectiveStackRenderer.postProcess(PerspectiveStackRenderer.java:63)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:669)
    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.workbench.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:70)
    at org.eclipse.e4.ui.workbench.renderers.swt.SashRenderer.processContents(SashRenderer.java:142)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:665)
    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.workbench.renderers.swt.SWTPartRenderer.processContents(SWTPartRenderer.java:70)
    at org.eclipse.e4.ui.workbench.renderers.swt.WBWRenderer.processContents(WBWRenderer.java:725)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeCreateGui(PartRenderingEngine.java:665)
    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.swt.PartRenderingEngine$4.run(PartRenderingEngine.java:1059)
    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(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    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)

I tried to re download eclipse and launch again. But I still get the same error.

Any help would be appreciated. Thank you.

Answer 1

I have similar issue. I manage to open eclipse without creating a new workspace by editing:

workspace/.metadata/.plugins/org.eclipse.e4.workbench/workbench.xmi

and removing from it all "persistedState" xml nodes.

UPDATE:

As other responses and comments says. Deleting file workspace/.metadata/.plugins/org.eclipse.e4.workbench/workbench.xmi seems to work well without side effects.

Answer 2

First go to below directory of your PC/Laptop/Desktop etc

**C:\Users\Username\eclipse-workspace.metadata.plugins\org.eclipse.e4.workbench**

workbench.xmi file - Delete this file without any worry

Now, start your eclipse and running great as usual.