Eclipse中lib下web.xml文件打不开，发生一下错误是怎么回事？提示错误Unable to create this part due to an internal error. Reason for the failure: Unable to open editor, unknown editor ID: org.xmen.ui.text.XMLTextEditor
org.eclipse.ui.PartInitException: Unable to open editor, unknown editor ID: org.xmen.ui.text.XMLTextEditor
at org.eclipse.ui.internal.EditorManager.openEditor(EditorManager.java:675)
at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditorBatched(WorkbenchPage.java:2593)
at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditor(WorkbenchPage.java:2528)
at org.eclipse.ui.internal.WorkbenchPage.access$10(WorkbenchPage.java:2520)
at org.eclipse.ui.internal.WorkbenchPage$9.run(WorkbenchPage.java:2505)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:67)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2500)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2477)
at com.genuitec.eclipse.struts.editor.multipage.StrutsConfigEditor.init(StrutsConfigEditor.java:469)
at org.eclipse.ui.internal.EditorManager.createSite(EditorManager.java:840)
at org.eclipse.ui.internal.EditorReference.createPartHelper(EditorReference.java:583)
at org.eclipse.ui.internal.EditorReference.createPart(EditorReference.java:372)
at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:566)
at org.eclipse.ui.internal.EditorReference.getEditor(EditorReference.java:214)
at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditorBatched(WorkbenchPage.java:2595)
at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditor(WorkbenchPage.java:2528)
at org.eclipse.ui.internal.WorkbenchPage.access$10(WorkbenchPage.java:2520)
at org.eclipse.ui.internal.WorkbenchPage$9.run(WorkbenchPage.java:2505)
at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:67)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2500)
at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2485)
at org.eclipse.ui.ide.IDE.openEditor(IDE.java:388)
at org.eclipse.ui.ide.IDE.openEditor(IDE.java:350)
at org.eclipse.jdt.internal.ui.javaeditor.EditorUtility.openInEditor(EditorUtility.java:275)
at org.eclipse.jdt.internal.ui.javaeditor.EditorUtility.openInEditor(EditorUtility.java:139)
at org.eclipse.jdt.internal.ui.actions.OpenActionUtil.open(OpenActionUtil.java:49)
at org.eclipse.jdt.ui.actions.OpenAction.run(OpenAction.java:190)
at org.eclipse.jdt.ui.actions.OpenAction.run(OpenAction.java:174)
at org.eclipse.jdt.ui.actions.SelectionDispatchAction.dispatchRun(SelectionDispatchAction.java:267)
at org.eclipse.jdt.ui.actions.SelectionDispatchAction.run(SelectionDispatchAction.java:243)
at org.eclipse.jdt.internal.ui.packageview.PackageExplorerActionGroup.handleOpen(PackageExplorerActionGroup.java:306)
at org.eclipse.jdt.internal.ui.packageview.PackageExplorerPart$4.open(PackageExplorerPart.java:653)
at org.eclipse.jface.viewers.StructuredViewer$2.run(StructuredViewer.java:817)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:37)
at org.eclipse.core.runtime.Platform.run(Platform.java:843)
at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:44)
at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:149)
at org.eclipse.jface.viewers.StructuredViewer.fireOpen(StructuredViewer.java:815)