Bug 220697 [Undo] Exceptions when validating a delete operation
Build ID: M20071023-1652 Steps To Reproduce: It is hard to reproduce. But it happens from time to time. From our editor, when user saves the file, we write to an IFile. We get the exception shown below. We are using File.setContents(stream, true, true, progressmonitor); So we are setting keep history to true and we are using force flag. More information: Problems occurred when invoking code from plug-in: "org.eclipse.core.resources". java.lang.NullPointerException at org.eclipse.ui.ide.undo.AbstractResourcesOperation.computeCreateStatus(AbstractResourcesOperation.java:164) at org.eclipse.ui.ide.undo.DeleteResourcesOperation.computeUndoableStatus(DeleteResourcesOperation.java:156) at org.eclipse.ui.internal.ide.undo.WorkspaceUndoMonitor.checkOperationHistory(WorkspaceUndoMonitor.java:235) at org.eclipse.ui.internal.ide.undo.WorkspaceUndoMonitor.access$4(WorkspaceUndoMonitor.java:209) at org.eclipse.ui.internal.ide.undo.WorkspaceUndoMonitor$1.resourceChanged(WorkspaceUndoMonitor.java:132) at org.eclipse.core.internal.events.NotificationManager$2.run(NotificationManager.java:282) at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:37) at org.eclipse.core.internal.events.NotificationManager.notify(NotificationManager.java:276) at org.eclipse.core.internal.events.NotificationManager.broadcastChanges(NotificationManager.java:148) at org.eclipse.core.internal.resources.Workspace.broadcastPostChange(Workspace.java:311) at org.eclipse.core.internal.resources.Workspace.endOperation(Workspace.java:1018) at org.eclipse.core.internal.resources.File.setContents(File.java:363) at org.eclipse.core.internal.resources.File.setContents(File.java:458) at com.fnfr.documents.helpers.DocumentHelper.writeToDocument(DocumentHelper.java:216) at com.fnfr.documents.helpers.DocumentHelper.writeToDocument(DocumentHelper.java:223) at com.fnfr.svt.ui.common.editors.FanfareFormEditor.saveDocumentToFile(FanfareFormEditor.java:979) at com.fnfr.svt.ui.common.editors.FanfareFormEditor$5.doPersistence(FanfareFormEditor.java:810) at com.fnfr.svt.ui.common.interfaces.AbstractPersistenceDelegate.persist(AbstractPersistenceDelegate.java:34) at com.fnfr.svt.ui.common.editors.FanfareFormEditor.managePersistence(FanfareFormEditor.java:935) at com.fnfr.svt.ui.common.editors.FanfareFormEditor.doSave(FanfareFormEditor.java:830) at org.eclipse.ui.internal.SaveableHelper$1.run(SaveableHelper.java:143) at org.eclipse.ui.internal.SaveableHelper$4.run(SaveableHelper.java:266) at org.eclipse.jface.operation.ModalContext.runInCurrentThread(ModalContext.java:369) at org.eclipse.jface.operation.ModalContext.run(ModalContext.java:313) at org.eclipse.jface.window.ApplicationWindow$1.run(ApplicationWindow.java:758) at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:67) at org.eclipse.jface.window.ApplicationWindow.run(ApplicationWindow.java:755) at org.eclipse.ui.internal.WorkbenchWindow.run(WorkbenchWindow.java:2451) at org.eclipse.ui.internal.SaveableHelper.runProgressMonitorOperation(SaveableHelper.java:274) at org.eclipse.ui.internal.SaveableHelper.runProgressMonitorOperation(SaveableHelper.java:253) at org.eclipse.ui.internal.SaveableHelper.savePart(SaveableHelper.java:148) at org.eclipse.ui.internal.EditorManager.savePart(EditorManager.java:1345) at org.eclipse.ui.internal.WorkbenchPage.savePart(WorkbenchPage.java:3184) at org.eclipse.ui.internal.WorkbenchPage.saveEditor(WorkbenchPage.java:3197) at org.eclipse.ui.internal.SaveAction.run(SaveAction.java:73) at org.eclipse.jface.action.Action.runWithEvent(Action.java:498) at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:545) at org.eclipse.jface.action.ActionContributionItem.access$2(ActionContributionItem.java:490) at org.eclipse.jface.action.ActionContributionItem$6.handleEvent(ActionContributionItem.java:443) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:66) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:938) at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3682) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3293) at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2389) at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2353) at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2219) at org.eclipse.ui.internal.Workbench$4.run(Workbench.java:466) at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:289) at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:461) at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149) at com.fnfr.svt.rcp.Application.runWorkbench(Application.java:144) at com.fnfr.svt.rcp.Application.start(Application.java:132) at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:153) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:106) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:76) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:363) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:176) 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:504) at org.eclipse.equinox.launcher.Main.basicRun(Main.java:443) at org.eclipse.equinox.launcher.Main.run(Main.java:1169)
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/ide/undo/AbstractWorkspaceOperation.java
*         <code>null</code> if there are no scheduling restrictions for
	 *         this operation.
	 * 
	 * @see IWorkspace#run(IWorkspaceRunnable, ISchedulingRule, int,
	 *      IProgressMonitor)
	 */
	protected ISchedulingRule getUndoSchedulingRule() {
		return getWorkspace().getRoot();
	}
	/**
	 * Return a scheduling rule appropriate for redoing this operation.
	 * 
	 * The default implementation considers the redo scheduling rule the same as
	 * the original execution scheduling rule.
	 * 
	 * @return the scheduling rule to use when redoing this operation, or
	 *         <code>null</code> if there are no scheduling restrictions for
	 *         this operation.
	 * 
	 * @see IWorkspace#run(IWorkspaceRunnable, ISchedulingRule, int,
	 *      IProgressMonitor)
	 */
	protected ISchedulingRule getRedoSchedulingRule() {
		return getExecuteSchedulingRule();
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.commands.operations.IAdvancedUndoableOperation2#setQuietCompute(boolean)
	 */