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Bug 332925

Summary: [DataBinding] Set input on TableViewer causes NPE while editing
Product: [Eclipse Project] Platform Reporter: Thomas Kratz <eiswind>
Component: UIAssignee: Platform UI Triaged <platform-ui-triaged>
Status: CLOSED WONTFIX QA Contact:
Severity: normal    
Priority: P3 CC: remy.suen
Version: 4.1   
Target Milestone: ---   
Hardware: PC   
OS: Windows 7   
Whiteboard: stalebug
Bug Depends on:    
Bug Blocks: 357568    
Attachments:
Description Flags
Patch on snippet to test replacing input none

Description Thomas Kratz CLA 2010-12-20 04:09:51 EST 
Build Identifier: 3.7M4

I don't know if this is a bug, but I found it a little strange. In this example stacktrace I need to rebind on save of the editor and it happens when users presses CTRL+S while editing. I worked around by .cancelEditing before setting the input. This example Stacktrace is generated on 4.1

java.lang.NullPointerException
	at org.eclipse.core.databinding.ValueBinding.doUpdate(ValueBinding.java:151)
	at org.eclipse.core.databinding.ValueBinding.updateTargetToModel(ValueBinding.java:112)
	at org.eclipse.jface.databinding.viewers.ObservableValueEditingSupport.saveCellEditorValue(ObservableValueEditingSupport.java:220)
	at org.eclipse.jface.viewers.ColumnViewerEditor.saveEditorValue(ColumnViewerEditor.java:455)
	at org.eclipse.jface.viewers.ColumnViewerEditor.applyEditorValue(ColumnViewerEditor.java:311)
	at org.eclipse.jface.viewers.ColumnViewer.applyEditorValue(ColumnViewer.java:411)
	at org.eclipse.jface.viewers.AbstractTableViewer.internalRefresh(AbstractTableViewer.java:646)
	at org.eclipse.jface.viewers.AbstractTableViewer.internalRefresh(AbstractTableViewer.java:636)
	at org.eclipse.jface.viewers.AbstractTableViewer$2.run(AbstractTableViewer.java:592)
	at org.eclipse.jface.viewers.StructuredViewer.preservingSelection(StructuredViewer.java:1422)
	at org.eclipse.jface.viewers.StructuredViewer.preservingSelection(StructuredViewer.java:1383)
	at org.eclipse.jface.viewers.AbstractTableViewer.inputChanged(AbstractTableViewer.java:590)
	at org.eclipse.jface.viewers.ContentViewer.setInput(ContentViewer.java:280)
	at org.eclipse.jface.viewers.StructuredViewer.setInput(StructuredViewer.java:1669)
	at de.eiswind.paris.client.ui.book.BookCategoriesPage.initDataBindings(BookCategoriesPage.java:234)
	at de.eiswind.paris.client.ui.book.BookCategoriesPage.rebind(BookCategoriesPage.java:100)
	at de.eiswind.paris.client.ui.book.BookEditor.rebind(BookEditor.java:236)
	at de.eiswind.paris.client.ui.book.BookEditor.saveHelper(BookEditor.java:224)
	at de.eiswind.paris.client.ui.book.BookEditor.doSave(BookEditor.java:192)
	at org.eclipse.ui.internal.SaveableHelper$2.run(SaveableHelper.java:151)
	at org.eclipse.ui.internal.SaveableHelper$5.run(SaveableHelper.java:274)
	at org.eclipse.jface.operation.ModalContext.runInCurrentThread(ModalContext.java:464)
	at org.eclipse.jface.operation.ModalContext.run(ModalContext.java:372)
	at org.eclipse.ui.internal.WorkbenchWindow$8.run(WorkbenchWindow.java:1527)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
	at org.eclipse.ui.internal.WorkbenchWindow.run(WorkbenchWindow.java:1524)
	at org.eclipse.ui.internal.SaveableHelper.runProgressMonitorOperation(SaveableHelper.java:282)
	at org.eclipse.ui.internal.SaveableHelper.runProgressMonitorOperation(SaveableHelper.java:261)
	at org.eclipse.ui.internal.SaveableHelper.savePart(SaveableHelper.java:156)
	at org.eclipse.ui.internal.e4.compatibility.CompatibilityPart.doSave(CompatibilityPart.java:247)
	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:52)
	at org.eclipse.e4.core.internal.di.InjectorImpl.invokeUsingClass(InjectorImpl.java:226)
	at org.eclipse.e4.core.internal.di.InjectorImpl.invokeUsingClass(InjectorImpl.java:232)
	at org.eclipse.e4.core.internal.di.InjectorImpl.invoke(InjectorImpl.java:196)
	at org.eclipse.e4.core.contexts.ContextInjectionFactory.invoke(ContextInjectionFactory.java:86)
	at org.eclipse.e4.ui.internal.workbench.PartServiceImpl.savePart(PartServiceImpl.java:1032)
	at org.eclipse.ui.internal.WorkbenchPage.saveSaveable(WorkbenchPage.java:2552)
	at org.eclipse.ui.internal.WorkbenchPage.saveEditor(WorkbenchPage.java:2570)
	at org.eclipse.ui.internal.SaveAction.run(SaveAction.java:76)
	at org.eclipse.jface.action.Action.runWithEvent(Action.java:498)
	at org.eclipse.jface.commands.ActionHandler.execute(ActionHandler.java:121)
	at org.eclipse.ui.internal.handlers.E4HandlerProxy.execute(E4HandlerProxy.java:58)
	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:52)
	at org.eclipse.e4.core.internal.di.InjectorImpl.invokeUsingClass(InjectorImpl.java:226)
	at org.eclipse.e4.core.internal.di.InjectorImpl.invoke(InjectorImpl.java:207)
	at org.eclipse.e4.core.contexts.ContextInjectionFactory.invoke(ContextInjectionFactory.java:123)
	at org.eclipse.e4.core.commands.internal.HandlerServiceImpl.executeHandler(HandlerServiceImpl.java:122)
	at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.executeCommand(KeyBindingDispatcher.java:266)
	at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.press(KeyBindingDispatcher.java:465)
	at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.processKeyEvent(KeyBindingDispatcher.java:515)
	at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.filterKeySequenceBindings(KeyBindingDispatcher.java:348)
	at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher.access$0(KeyBindingDispatcher.java:294)
	at org.eclipse.e4.ui.bindings.keys.KeyBindingDispatcher$KeyDownFilter.handleEvent(KeyBindingDispatcher.java:76)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
	at org.eclipse.swt.widgets.Display.filterEvent(Display.java:1254)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1052)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1077)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1062)
	at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:1103)
	at org.eclipse.swt.widgets.Text.sendKeyEvent(Text.java:1454)
	at org.eclipse.swt.widgets.Widget.sendKeyEvent(Widget.java:1099)
	at org.eclipse.swt.widgets.Widget.wmChar(Widget.java:1508)
	at org.eclipse.swt.widgets.Control.WM_CHAR(Control.java:4273)
	at org.eclipse.swt.widgets.Text.WM_CHAR(Text.java:2252)
	at org.eclipse.swt.widgets.Control.windowProc(Control.java:4165)
	at org.eclipse.swt.widgets.Text.windowProc(Text.java:2247)
	at org.eclipse.swt.widgets.Display.windowProc(Display.java:4891)
	at org.eclipse.swt.internal.win32.OS.DispatchMessageW(Native Method)
	at org.eclipse.swt.internal.win32.OS.DispatchMessage(OS.java:2465)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3673)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$6.run(PartRenderingEngine.java:808)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:724)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:89)
	at org.eclipse.ui.internal.Workbench$3.run(Workbench.java:534)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:516)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
	at de.eiswind.paris.client.core.Application.start(Application.java:35)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:369)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
	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:622)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:577)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1410)
	at org.eclipse.equinox.launcher.Main.main(Main.java:1386)

Reproducible: Always

Steps to Reproduce:
1. Create a TableViewer with Observable Content Provider
2. Create an Inline TextCellEditor with Databinding
3. Edit the Cell
4. Set a new Input while editing is ongoing
Comment 1 Matthew Hall CLA 2011-09-19 02:50:10 EDT 
The stack trace seems to indicate that the source observable (observing the cell editor control) is being disposed. Widget observables dispose themselves when the source widget is disposed, so that might be the problem somehow.

I'll try to reproduce with one of a cell editor example snippet and get back to you.
Comment 2 Matthew Hall CLA 2011-09-20 00:22:53 EDT 
Created attachment 203635 [details]
Patch on snippet to test replacing input

I tried to duplicate this behavior with this patch, but could not get the same exception.

Thomas, are you still able to duplicate this problem in Eclipse Indigo?
Comment 3 Thomas Kratz CLA 2011-09-20 02:52:52 EDT 
Yes I still see that, last case I saw something similar was when I tried to remove an entry from the input while editing. It happens only when the editor is active. Maybe its a ComboBoxEditor?
Comment 4 Matthew Hall CLA 2011-09-20 09:40:04 EDT 
Can you modify the attached patch to demonstrate the error? I'd like to help you, but I'm not sure where the problem lies.
Comment 5 Eclipse Genie CLA 2019-11-05 11:38:19 EST 
This bug hasn't had any activity in quite some time. Maybe the problem got resolved, was a duplicate of something else, or became less pressing for some reason - or maybe it's still relevant but just hasn't been looked at yet.

If you have further information on the current state of the bug, please add it. The information can be, for example, that the problem still occurs, that you still want the feature, that more information is needed, or that the bug is (for whatever reason) no longer relevant.

--
The automated Eclipse Genie.