Widget disposed error on paste

[AObuchow]

While testing out Sample Commadner on windows, I got the following stacktrace in the problem view.

org.eclipse.core.commands.ExecutionException: Error executing 'org.eclipse.ui.edit.paste': org.eclipse.swt.SWTException: Widget is disposed
	at org.eclipse.e4.core.commands.internal.HandlerServiceHandler.execute(HandlerServiceHandler.java:170)
	at org.eclipse.core.commands.Command.executeWithChecks(Command.java:488)
	at org.eclipse.core.commands.ParameterizedCommand.executeWithChecks(ParameterizedCommand.java:487)
	at org.eclipse.e4.core.commands.internal.HandlerServiceImpl.executeHandler(HandlerServiceImpl.java:213)
	at org.eclipse.ui.internal.handlers.LegacyHandlerService.executeCommand(LegacyHandlerService.java:389)
	at org.eclipse.ui.menus.CommandContributionItem.handleWidgetSelection(CommandContributionItem.java:785)
	at org.eclipse.ui.menus.CommandContributionItem.lambda$3(CommandContributionItem.java:762)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:89)
	at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4213)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1037)
	at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4030)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3630)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1158)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:338)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1047)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:155)
	at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:658)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:338)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:557)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:154)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:150)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:203)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:137)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:107)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:401)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:255)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:567)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:657)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:594)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1447)
Caused by: org.eclipse.e4.core.di.InjectionException: org.eclipse.swt.SWTException: Widget is disposed
	at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:68)
	at org.eclipse.e4.core.internal.di.InjectorImpl.invokeUsingClass(InjectorImpl.java:319)
	at org.eclipse.e4.core.internal.di.InjectorImpl.invoke(InjectorImpl.java:253)
	at org.eclipse.e4.core.contexts.ContextInjectionFactory.invoke(ContextInjectionFactory.java:173)
	at org.eclipse.e4.core.commands.internal.HandlerServiceHandler.execute(HandlerServiceHandler.java:156)
	... 32 more
Caused by: org.eclipse.swt.SWTException: Widget is disposed
	at org.eclipse.swt.SWT.error(SWT.java:4723)
	at org.eclipse.swt.SWT.error(SWT.java:4638)
	at org.eclipse.swt.SWT.error(SWT.java:4609)
	at org.eclipse.swt.dnd.DND.error(DND.java:296)
	at org.eclipse.swt.dnd.DND.error(DND.java:241)
	at org.eclipse.swt.dnd.Clipboard.checkWidget(Clipboard.java:139)
	at org.eclipse.swt.dnd.Clipboard.getContents(Clipboard.java:331)
	at org.eclipse.swt.dnd.Clipboard.getContents(Clipboard.java:285)
	at com.aobuchow.sample.commander.FileClipBoard.paste(FileClipBoard.java:47)
	at com.aobuchow.sample.commander.editor.FileManagerEditor.paste(FileManagerEditor.java:532)
	at com.aobuchow.sample.commander.handlers.PasteHandler.execute(PasteHandler.java:17)
	at org.eclipse.ui.internal.handlers.HandlerProxy.execute(HandlerProxy.java:283)
	at org.eclipse.ui.internal.handlers.E4HandlerProxy.execute(E4HandlerProxy.java:97)
	at jdk.internal.reflect.GeneratedMethodAccessor62.invoke(Unknown Source)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:567)
	at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:58)
	... 36 more

Seems the clipboard got disposed

[AObuchow]

I believe the issue is that when a FIleManagerEditor was being disposed of, it'd dispose of the FileClipBoard.
The FileClipBoard should only be disposed when the plugin shuts down, although this was causing issues related to https://bugs.eclipse.org/bugs/show_bug.cgi?id=265741

@ingomohr have you run into this issue before by any chance?

[ingomohr]

I believe the issue is that when a FIleManagerEditor was being disposed of, it'd dispose of the FileClipBoard.
The FileClipBoard should only be disposed when the plugin shuts down, although this was causing issues related to https://bugs.eclipse.org/bugs/show_bug.cgi?id=265741

@ingomohr have you run into this issue before by any chance?

@AObuchow No, not yet. I haven't checked the code yet, but maybe the FileClipBoard is bound to the dispose-listener of the FIleManagerEditor (if it has some).

[AObuchow]

@ingomohr yes that was the issue :) now I just have to find out when/how to properly dispose the clipboard

[ingomohr]

@ingomohr yes that was the issue :) now I just have to find out when/how to properly dispose the clipboard

IRC we dispose the Clipboard right away everytime we use it. For that I wrote a util class to e.g. push a StructuredSelection to the clipboard - using some ClipboardUtil.pushSelection(sel) which creates the Clipboard, pushes the given selection and then disposes the Clipboard again.

Maybe, there's a better option for this (the class is really old) - but it's working.