Hi,
I also have same problem. i have downloaded EclipseJavaCC-1.5.12 from
http://eclipse-javacc.sourceforge.net and unzipped to eclipse but still it is not allowing me to create .jj file. it showing error that
Unable to create this part due to an internal error. Reason for the failure: The editor class could not be instantiated. This usually indicates that the editor's class name was mistyped in plugin.xml.
java.lang.ClassNotFoundException: sf.eclipse.javacc.editors.JJEditor
at org.eclipse.osgi.framework.internal.core.BundleLoader.findClass(BundleLoader.java:405)
at org.eclipse.osgi.framework.internal.core.BundleLoader.findClass(BundleLoader.java:350)
at org.eclipse.osgi.framework.adaptor.core.AbstractClassLoader.loadClass(AbstractClassLoader.java:78)
at java.lang.ClassLoader.loadClass(Unknown Source)
at org.eclipse.osgi.framework.internal.core.BundleLoader.loadClass(BundleLoader.java:275)
at org.eclipse.osgi.framework.internal.core.BundleHost.loadClass(BundleHost.java:227)
at org.eclipse.osgi.framework.internal.core.AbstractBundle.loadClass(AbstractBundle.java:1248)
at org.eclipse.core.internal.registry.ConfigurationElement.createExecutableExtension(ConfigurationElement.java:152)
at org.eclipse.core.internal.registry.ConfigurationElement.createExecutableExtension(ConfigurationElement.java:142)
at org.eclipse.core.internal.registry.ConfigurationElement.createExecutableExtension(ConfigurationElement.java:129)
at org.eclipse.core.internal.registry.ConfigurationElementHandle.createExecutableExtension(ConfigurationElementHandle.java:48)
at org.eclipse.ui.internal.WorkbenchPlugin$1.run(WorkbenchPlugin.java:240)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:69)
at org.eclipse.ui.internal.WorkbenchPlugin.createExtension(WorkbenchPlugin.java:236)
at org.eclipse.ui.internal.registry.EditorDescriptor.createEditor(EditorDescriptor.java:252)
at org.eclipse.ui.internal.EditorManager.createPart(EditorManager.java:842)
at org.eclipse.ui.internal.EditorReference.createPartHelper(EditorReference.java:562)
at org.eclipse.ui.internal.EditorReference.createPart(EditorReference.java:384)
at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:552)
at org.eclipse.ui.internal.EditorReference.getEditor(EditorReference.java:223)
at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditorBatched(WorkbenchPage.java:2362)
at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditor(WorkbenchPage.java:2295)
at org.eclipse.ui.internal.WorkbenchPage.access$9(WorkbenchPage.java:2287)
at org.eclipse.ui.internal.WorkbenchPage$9.run(WorkbenchPage.java:2273)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:69)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2268)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2249)
at org.eclipse.ui.ide.IDE.openEditor(IDE.java:371)
at org.eclipse.ui.ide.IDE.openEditor(IDE.java:334)
at org.eclipse.jdt.internal.ui.javaeditor.EditorUtility.openInEditor(EditorUtility.java:251)
at org.eclipse.jdt.internal.ui.javaeditor.EditorUtility.openInEditor(EditorUtility.java:131)
at org.eclipse.jdt.internal.ui.actions.OpenActionUtil.open(OpenActionUtil.java:49)
at org.eclipse.jdt.ui.actions.OpenAction.run(OpenAction.java:169)
at org.eclipse.jdt.ui.actions.OpenAction.run(OpenAction.java:153)
at org.eclipse.jdt.ui.actions.SelectionDispatchAction.dispatchRun(SelectionDispatchAction.java:222)
at org.eclipse.jdt.ui.actions.SelectionDispatchAction.run(SelectionDispatchAction.java:198)
at org.eclipse.jdt.internal.ui.packageview.PackageExplorerActionGroup.handleOpen(PackageExplorerActionGroup.java:296)
at org.eclipse.jdt.internal.ui.packageview.PackageExplorerPart$4.open(PackageExplorerPart.java:869)
at org.eclipse.jface.viewers.StructuredViewer$2.run(StructuredViewer.java:741)
at org.eclipse.core.internal.runtime.InternalPlatform.run(InternalPlatform.java:1044)
at org.eclipse.core.runtime.Platform.run(Platform.java:783)
at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:44)
at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:148)
at org.eclipse.jface.viewers.StructuredViewer.fireOpen(StructuredViewer.java:739)
at org.eclipse.jface.viewers.StructuredViewer.handleOpen(StructuredViewer.java:968)
at org.eclipse.jface.viewers.StructuredViewer$6.handleOpen(StructuredViewer.java:1067)
at org.eclipse.jface.util.OpenStrategy.fireOpenEvent(OpenStrategy.java:243)
at org.eclipse.jface.util.OpenStrategy.access$2(OpenStrategy.java:238)
at org.eclipse.jface.util.OpenStrategy$1.handleEvent(OpenStrategy.java:277)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:66)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:843)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3125)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:2758)
at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:1699)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:1663)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:367)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:143)
at org.eclipse.ui.internal.ide.IDEApplication.run(IDEApplication.java:103)
at org.eclipse.core.internal.runtime.PlatformActivator$1.run(PlatformActivator.java:226)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:376)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:163)
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.core.launcher.Main.invokeFramework(Main.java:334)
at org.eclipse.core.launcher.Main.basicRun(Main.java:278)
at org.eclipse.core.launcher.Main.run(Main.java:973)
at org.eclipse.core.launcher.Main.main(Main.java:948)