Description Pierre-Charles David 2014-04-30 10:36:55 EDT

Steps to reproduce:
1. Create a basic project, create a VSM inside and open it in the VSM editor.
2. Close the project.

It works, but produces a new entry in the error log:

eclipse.buildId=4.4.0.I20140306-1200
java.version=1.8.0
java.vendor=Oracle Corporation
BootLoader constants: OS=linux, ARCH=x86_64, WS=gtk, NL=fr_FR
Command-line arguments:  -os linux -ws gtk -arch x86_64

org.eclipse.ui
Error
Wed Apr 30 16:29:57 CEST 2014
Unhandled event loop exception

org.eclipse.swt.SWTException: Failed to execute runnable (java.lang.NullPointerException)
	at org.eclipse.swt.SWT.error(SWT.java:4441)
	at org.eclipse.swt.SWT.error(SWT.java:4356)
	at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:139)
	at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3748)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3396)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$9.run(PartRenderingEngine.java:1122)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
	at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1006)
	at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:147)
	at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:630)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:574)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150)
	at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:125)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:133)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:103)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:378)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:232)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:483)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:648)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:603)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1462)
	at org.eclipse.equinox.launcher.Main.main(Main.java:1438)
Caused by: java.lang.NullPointerException
	at org.eclipse.ui.part.MultiPageEditorPart.deactivateSite(MultiPageEditorPart.java:930)
	at org.eclipse.ui.part.MultiPageEditorPart.dispose(MultiPageEditorPart.java:501)
	at org.eclipse.sirius.editor.editorPlugin.SiriusEditor.dispose(SiriusEditor.java:1319)
	at org.eclipse.sirius.editor.tools.internal.presentation.CustomSiriusEditor.dispose(CustomSiriusEditor.java:370)
	at org.eclipse.sirius.editor.editorPlugin.SiriusEditor$3$1.run(SiriusEditor.java:409)
	at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
	at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:136)
	... 24 more


org.eclipse.sirius.editor.editorPlugin.SiriusEditor$3$1.run(SiriusEditor.java:409) seems to be the culprit: on the line above we explicitly close the editor, which already calls dispose() on it, and then on line 409 we call dispose() again. dispose() then tries to access resources which were already removed before. The code in SiriusEditor is very old, maybe it dates from old versions of Eclipse where closing the editor did not call dispose? We need to check if the NPE is specific to Luna, to e4, or if it is present in all the releases we support.