Details
-
Bug
-
Status: Closed
-
Major
-
Resolution: Fixed
-
0.15
-
None
-
None
Description
We are seeing the follow NPE whilst connecting the Qpid Management Console to the Broker. The NPE seems to be non-deterministic.
java.lang.NullPointerException
at org.apache.qpid.management.ui.views.NavigationView.doesMBeanNodeAlreadyExist(NavigationView.java:584)
at org.apache.qpid.management.ui.views.NavigationView.addManagedBean(NavigationView.java:685)
at org.apache.qpid.management.ui.views.NavigationView.populateServer(NavigationView.java:510)
at org.apache.qpid.management.ui.views.NavigationView.addNewServer(NavigationView.java:314)
at org.apache.qpid.management.ui.actions.AddServer.run(AddServer.java:72)
at org.eclipse.ui.internal.PluginAction.runWithEvent(PluginAction.java:251)
at org.eclipse.ui.internal.WWinPluginAction.runWithEvent(WWinPluginAction.java:229)
at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:583)
at org.eclipse.jface.action.ActionContributionItem.access$2(ActionContributionItem.java:500)
at org.eclipse.jface.action.ActionContributionItem$6.handleEvent(ActionContributionItem.java:452)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1158)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3401)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3033)
at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2382)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2346)
at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2198)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:493)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:288)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:488)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
at org.apache.qpid.management.ui.Application.run(Application.java:46)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.eclipse.equinox.internal.app.EclipseAppContainer.callMethodWithException(EclipseAppContainer.java:574)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:195)
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:386)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:549)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:504)
at org.eclipse.equinox.launcher.Main.run(Main.java:1236)
at org.eclipse.equinox.launcher.Main.main(Main.java:1212)
Investigation has shown that the NPE is caused between an interaction between the ShutdownPlugin and the NavigationView#addManagedBean method of the UI.
As the Shutdown Plugin has no name (only a type), if it is processed by the addManagedBean algorithm first all is well. However if it is processed after another MBean the NPE occurs. The non deterministic nature of the NPE is caused by the order in which the MBeans are reported.
Removing the Shutdown plugin from the lib/plugin directory works around the problem.