java.lang.NullPointerException at org.eclipse.e4.ui.internal.workbench.PartServiceImpl.switchPerspective(PartServiceImpl.java:590) at org.eclipse.e4.ui.workbench.renderers.swt.PerspectiveStackRenderer.showTab(PerspectiveStackRenderer.java:127) at org.eclipse.e4.ui.workbench.renderers.swt.LazyStackRenderer$1.handleEvent(LazyStackRenderer.java:69) at org.eclipse.e4.ui.services.internal.events.UIEventHandler$1.run(UIEventHandler.java:40) at org.eclipse.swt.widgets.Synchronizer.syncExec(Synchronizer.java:187) at org.eclipse.ui.internal.UISynchronizer.syncExec(UISynchronizer.java:156) at org.eclipse.swt.widgets.Display.syncExec(Display.java:4734) at org.eclipse.e4.ui.internal.workbench.swt.E4Application$1.syncExec(E4Application.java:218) at org.eclipse.e4.ui.services.internal.events.UIEventHandler.handleEvent(UIEventHandler.java:36) at org.eclipse.equinox.internal.event.EventHandlerWrapper.handleEvent(EventHandlerWrapper.java:197) at org.eclipse.equinox.internal.event.EventHandlerTracker.dispatchEvent(EventHandlerTracker.java:197) at org.eclipse.equinox.internal.event.EventHandlerTracker.dispatchEvent(EventHandlerTracker.java:1) at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:230) at org.eclipse.osgi.framework.eventmgr.ListenerQueue.dispatchEventSynchronous(ListenerQueue.java:148) at org.eclipse.equinox.internal.event.EventAdminImpl.dispatchEvent(EventAdminImpl.java:135) at org.eclipse.equinox.internal.event.EventAdminImpl.sendEvent(EventAdminImpl.java:78) at org.eclipse.equinox.internal.event.EventComponent.sendEvent(EventComponent.java:39) at org.eclipse.e4.ui.services.internal.events.EventBroker.send(EventBroker.java:81) at org.eclipse.e4.ui.internal.workbench.UIEventPublisher.notifyChanged(UIEventPublisher.java:59) at org.eclipse.emf.common.notify.impl.BasicNotifierImpl.eNotify(BasicNotifierImpl.java:374) at org.eclipse.e4.ui.model.application.ui.advanced.impl.PerspectiveStackImpl.setSelectedElement(PerspectiveStackImpl.java:135) at org.eclipse.e4.ui.model.application.ui.advanced.impl.PerspectiveStackImpl.setSelectedElement(PerspectiveStackImpl.java:1) at org.eclipse.e4.ui.workbench.addons.perspectiveswitcher.PerspectiveSwitcher$16.widgetSelected(PerspectiveSwitcher.java:622) at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:248) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84) at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4353) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1061) at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4172) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3761) at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$9.run(PartRenderingEngine.java:1151) at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332) at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1032) at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:148) at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:636) at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332) at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:579) at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150) at mailapp.Application.start(Application.java:20) at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:380) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:235) 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:1465) at org.eclipse.equinox.launcher.Main.main(Main.java:1438)