When calling stopProviding more than once in these classes (for example deploying MBean, stopProviding(), startProviding(), undeploying MBean) a NullPointerException occurs.

Example stack trace:

javax.management.RuntimeMBeanException
at org.jboss.mx.interceptor.ReflectedDispatcher.handleInvocationExceptions(ReflectedDispatcher.java:176)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:163)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:86)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.varia.scheduler.AbstractScheduleProvider.stopScheduleProviderService(AbstractScheduleProvider.java:227)
at org.jboss.varia.scheduler.AbstractScheduleProvider.stopService(AbstractScheduleProvider.java:202)
at org.jboss.system.ServiceMBeanSupport.jbossInternalStop(ServiceMBeanSupport.java:315)
at org.jboss.system.ServiceMBeanSupport.jbossInternalLifecycle(ServiceMBeanSupport.java:247)
at sun.reflect.GeneratedMethodAccessor3.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:86)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.system.ServiceController$ServiceProxy.invoke(ServiceController.java:978)
at $Proxy0.stop(Unknown Source)
at org.jboss.system.ServiceController.stop(ServiceController.java:508)
at sun.reflect.GeneratedMethodAccessor112.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:86)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.mx.util.MBeanProxyExt.invoke(MBeanProxyExt.java:210)
at $Proxy4.stop(Unknown Source)
at org.jboss.deployment.SARDeployer.stop(SARDeployer.java:336)
at org.jboss.deployment.MainDeployer.stop(MainDeployer.java:667)
at org.jboss.deployment.MainDeployer.undeploy(MainDeployer.java:638)
at org.jboss.deployment.MainDeployer.undeploy(MainDeployer.java:632)
at org.jboss.deployment.MainDeployer.undeploy(MainDeployer.java:615)
at sun.reflect.GeneratedMethodAccessor132.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.interceptor.AbstractInterceptor.invoke(AbstractInterceptor.java:133)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.interceptor.ModelMBeanOperationInterceptor.invoke(ModelMBeanOperationInterceptor.java:142)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.mx.util.MBeanProxyExt.invoke(MBeanProxyExt.java:210)
at $Proxy9.undeploy(Unknown Source)
at org.jboss.deployment.scanner.URLDeploymentScanner.undeploy(URLDeploymentScanner.java:450)
at org.jboss.deployment.scanner.URLDeploymentScanner.scan(URLDeploymentScanner.java:570)
at org.jboss.deployment.scanner.AbstractDeploymentScanner$ScannerThread.doScan(AbstractDeploymentScanner.java:263)
at org.jboss.deployment.scanner.AbstractDeploymentScanner$ScannerThread.loop(AbstractDeploymentScanner.java:274)
at org.jboss.deployment.scanner.AbstractDeploymentScanner$ScannerThread.run(AbstractDeploymentScanner.java:225)
Caused by: javax.management.RuntimeMBeanException
at org.jboss.mx.interceptor.ReflectedDispatcher.handleInvocationExceptions(ReflectedDispatcher.java:176)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:163)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:86)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.varia.scheduler.ScheduleManager.unregisterProvider(ScheduleManager.java:242)
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.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
... 52 more
Caused by: javax.management.RuntimeMBeanException
at org.jboss.mx.interceptor.ReflectedDispatcher.handleInvocationExceptions(ReflectedDispatcher.java:176)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:163)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:94)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:86)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:659)
at org.jboss.varia.scheduler.AbstractScheduleProvider.removeSchedule(AbstractScheduleProvider.java:163)
at org.jboss.varia.scheduler.XMLScheduleProvider.stopProviding(XMLScheduleProvider.java:239)
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.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
... 62 more
Caused by: java.lang.NullPointerException
at org.jboss.varia.scheduler.ScheduleManager.removeSchedule(ScheduleManager.java:332)
at sun.reflect.GeneratedMethodAccessor153.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:155)
... 73 more

Looking at the implementation:

/**

• Stops the Provider from providing causing
• the provider to remove the Schedule
  *
• @jmx:managed-operation
  */
  public void stopProviding() {
  Iterator i = mIDList.iterator();
  while( i.hasNext() )
  Unknown macro: { Integer lID = (Integer) i.next(); try { removeSchedule( lID.intValue() ); } catch( JMException jme ) { log.error( "Could not remove Schedule in stop providing", jme ); } }

  }

it seems to lack i.remove() while iterating. During next stopProviding() call a non-existing schedule is being removed and NullPointerException is thrown. As a result no further schedules are removed.