NullPointerException thrown while calling SchedulerEngineHelperImpl.unregister

• Type: Bug
• Status: Resolved
• Resolution: No Longer Reproducible
• Affects Version/s: 7.0.0 DXP FP32
• Fix Version/s: 7.0.X, Master
• Component/s: Portal Services > Scheduler
• Labels: None

Exception below is thrown while shutting down the portal:

java.lang.NullPointerException
	at com.liferay.portal.scheduler.internal.SchedulerEngineHelperImpl.lambda$unregister$0(SchedulerEngineHelperImpl.java:687)
	at java.util.concurrent.ConcurrentHashMap.compute(ConcurrentHashMap.java:1853)
	at com.liferay.portal.scheduler.internal.SchedulerEngineHelperImpl.unregister(SchedulerEngineHelperImpl.java:684)
	at com.liferay.recent.documents.web.internal.messaging.RecentDocumentsMessageListener.deactivate(RecentDocumentsMessageListener.java:91)
	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:498)
	at org.apache.felix.scr.impl.inject.BaseMethod.invokeMethod(BaseMethod.java:224)
	at org.apache.felix.scr.impl.inject.BaseMethod.access$500(BaseMethod.java:39)
	at org.apache.felix.scr.impl.inject.BaseMethod$Resolved.invoke(BaseMethod.java:617)
	at org.apache.felix.scr.impl.inject.BaseMethod.invoke(BaseMethod.java:501)
	at org.apache.felix.scr.impl.inject.ActivateMethod.invoke(ActivateMethod.java:302)
	at org.apache.felix.scr.impl.inject.ActivateMethod.invoke(ActivateMethod.java:294)
	at org.apache.felix.scr.impl.manager.SingleComponentManager.disposeImplementationObject(SingleComponentManager.java:343)
	at org.apache.felix.scr.impl.manager.SingleComponentManager.deleteComponent(SingleComponentManager.java:152)
	at org.apache.felix.scr.impl.manager.AbstractComponentManager.doDeactivate(AbstractComponentManager.java:813)
	at org.apache.felix.scr.impl.manager.AbstractComponentManager.deactivateInternal(AbstractComponentManager.java:787)
	at org.apache.felix.scr.impl.manager.DependencyManager.deactivateComponentManager(DependencyManager.java:2225)
	at org.apache.felix.scr.impl.manager.DependencyManager.access$500(DependencyManager.java:55)
	at org.apache.felix.scr.impl.manager.DependencyManager$SingleStaticCustomizer.removedService(DependencyManager.java:1082)
	at org.apache.felix.scr.impl.manager.DependencyManager$SingleStaticCustomizer.removedService(DependencyManager.java:968)
	at org.apache.felix.scr.impl.manager.ServiceTracker$Tracked.customizerRemoved(ServiceTracker.java:1241)
	at org.apache.felix.scr.impl.manager.ServiceTracker$Tracked.customizerRemoved(ServiceTracker.java:1136)
	at org.apache.felix.scr.impl.manager.ServiceTracker$AbstractTracked.untrack(ServiceTracker.java:996)
	at org.apache.felix.scr.impl.manager.ServiceTracker$Tracked.serviceChanged(ServiceTracker.java:1175)
	at org.apache.felix.scr.impl.BundleComponentActivator$ListenerInfo.serviceChanged(BundleComponentActivator.java:127)
	at org.eclipse.osgi.internal.serviceregistry.FilteredServiceListener.serviceChanged(FilteredServiceListener.java:109)
	at org.eclipse.osgi.internal.framework.BundleContextImpl.dispatchEvent(BundleContextImpl.java:917)
	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.osgi.internal.serviceregistry.ServiceRegistry.publishServiceEventPrivileged(ServiceRegistry.java:862)
	at org.eclipse.osgi.internal.serviceregistry.ServiceRegistry.publishServiceEvent(ServiceRegistry.java:801)
	at org.eclipse.osgi.internal.serviceregistry.ServiceRegistrationImpl.unregister(ServiceRegistrationImpl.java:222)
	at com.liferay.registry.internal.ServiceRegistrationWrapper.unregister(ServiceRegistrationWrapper.java:77)
	at com.liferay.portal.servlet.MainServlet.destroy(MainServlet.java:150)
	at org.apache.catalina.core.StandardWrapper.unload(StandardWrapper.java:1443)
	at org.apache.catalina.core.StandardWrapper.stopInternal(StandardWrapper.java:1775)
	at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:224)
	at org.apache.catalina.core.StandardContext.stopInternal(StandardContext.java:5465)
	at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:224)
	at org.apache.catalina.core.ContainerBase$StopChild.call(ContainerBase.java:1424)
	at org.apache.catalina.core.ContainerBase$StopChild.call(ContainerBase.java:1413)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)

Suggested fix:

https://github.com/liferay/liferay-portal/blob/master/modules/apps/foundation/portal-scheduler/portal-scheduler/src/main/java/com/liferay/portal/scheduler/internal/SchedulerEngineHelperImpl.java#L684

Replace call to

 _serviceRegistrations.compute 

with

 computeIfPresent