Description Andrey Loskutov 2017-01-09 07:18:56 EST

No steps to reproduce, but the error root cause is clear: async tasks have always check if their targets are still alive.

Regression from 9dc142efc9b8252e1c07716db1286e1cbe0e1c7e bug 495007.

eclipse.buildId=4.7.0.I20161121-2000
java.version=1.8.0_111
java.vendor=Oracle Corporation
BootLoader constants: OS=linux, ARCH=x86_64, WS=gtk, NL=en_US
Command-line arguments:  -os linux -ws gtk -arch x86_64

org.eclipse.ui
Error
Mon Jan 09 12:49:25 CET 2017
Unhandled event loop exception

org.eclipse.swt.SWTException: Widget is disposed
	at org.eclipse.swt.SWT.error(SWT.java:4533)
	at org.eclipse.swt.SWT.error(SWT.java:4448)
	at org.eclipse.swt.SWT.error(SWT.java:4419)
	at org.eclipse.swt.widgets.Widget.error(Widget.java:487)
	at org.eclipse.swt.widgets.Widget.checkWidget(Widget.java:424)
	at org.eclipse.swt.widgets.Label.setText(Label.java:669)
	at org.eclipse.jface.wizard.ProgressMonitorPart.done(ProgressMonitorPart.java:175)
	at org.eclipse.ui.internal.wizards.datatransfer.DelegateProgressMonitorInUIThreadAndPreservingFocus.lambda$5(DelegateProgressMonitorInUIThreadAndPreservingFocus.java:81)
	at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:37)
	at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:182)
	at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:4483)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:4096)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$4.run(PartRenderingEngine.java:1133)
	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:153)
	at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:698)

I have a trivial patch.