NPE caused by areObjectsEqual passed with storedMatch==null

Seeing these continually throughout our logs:

2015-03-17 05:11:30,428 | WARN | ds-oper-thread-0 | StatisticsManagerImpl | 246 - org.opendaylight.openflowplugin.applications.statistics-manager - 0.1.0.SNAPSHOT | Unhandled exception during processing statistics. Restarting transaction chain.
java.lang.NullPointerException
at org.opendaylight.openflowplugin.applications.statistics.manager.impl.helper.MatchComparatorFactory$11.areObjectsEqual(MatchComparatorFactory.java:211)[246:org.opendaylight.openflowplugin.applications.statistics-manager:0.1.0.SNAPSHOT]
at org.opendaylight.openflowplugin.applications.statistics.manager.impl.helper.MatchComparatorFactory$11.areObjectsEqual(MatchComparatorFactory.java:205)[246:org.opendaylight.openflowplugin.applications.statistics-manager:0.1.0.SNAPSHOT]

On further investigation:

FlowComparatorFactory Line144 calls
-> matchComp.areObjectsEqual(statsMatch, storedMatch) where storedMatch==null.

MatchComparatorFactory Line211 tries to access storedMatch.getEthernetMatch() where storedMatch==null.

The real question is whether the case where storedMatch should ever be null…

I think it is, as it is all kicked off by StatListenCommitFlow Line360, for which our cfgFlow is a “drop|null” which won’t have a match…

Actually this repeated pattern of “areObjectsEqual()” doesn’t seem to check if parameters are null before accessing their getters.

areObjectsEqual should
if(storedMatch==null) return false;

Submitting patch for fix with UnitTest