Exception in thread "ForkJoinPool-2-worker-2" java.lang.NullPointerException: Cannot invoke "com.google.common.util.concurrent.FluentFuture.addCallback(com.google.common.util.concurrent.FutureCallback, java.util.concurrent.Executor)" because the return value of "org.opendaylight.mdsal.binding.api.WriteTransaction.commit()" is null
	at org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterSequential$FlowHandlerTask.run(FlowWriterSequential.java:135)
	at java.base/java.util.concurrent.ForkJoinTask$RunnableExecuteAction.exec(ForkJoinTask.java:1395)
	at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:373)
	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1182)
	at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1655)
	at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1622)
	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:165)
[ForkJoinPool-7-worker-1] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowReader - Flow found: mockNode
[ForkJoinPool-7-worker-1] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowReader - Total Flows read: 1
Exception in thread "ForkJoinPool-2-worker-3" java.lang.NullPointerException: Cannot invoke "com.google.common.util.concurrent.FluentFuture.addCallback(com.google.common.util.concurrent.FutureCallback, java.util.concurrent.Executor)" because the return value of "org.opendaylight.mdsal.binding.api.WriteTransaction.commit()" is null
	at org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterConcurrent$FlowHandlerTask.run(FlowWriterConcurrent.java:134)
	at java.base/java.util.concurrent.ForkJoinTask$RunnableExecuteAction.exec(ForkJoinTask.java:1395)
	at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:373)
	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1182)
	at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1655)
	at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1622)
	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:165)
[main] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterTxChain - Using Ping Pong Flow Tester Impl
[main] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterTxChain - Using Transaction Chain Flow Writer Impl
[main] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterTxChain - Number of Txn for dpId: openflow:1 is: 10
[main] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterTxChain - Creating new txChain: Mock for TransactionChain, hashCode: 627677863 for dpid: openflow:1
[main] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterTxChain - Completed all flows installation for: dpid: openflow:1 in 1020163928069ns
[main] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterTxChain - Completed FlowHandlerTask thread for dpid: openflow:1
[main] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterTxChain - Using Ping Pong Flow Tester Impl
[main] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterTxChain - Using Transaction Chain Flow Writer Impl
[main] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterTxChain - Number of Txn for dpId: openflow:1 is: 10
[main] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterTxChain - Creating new txChain: Mock for TransactionChain, hashCode: 2040477002 for dpid: openflow:1
[main] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterTxChain - Completed all flows installation for: dpid: openflow:1 in 9462732ns
[main] INFO org.opendaylight.openflowplugin.applications.bulk.o.matic.FlowWriterTxChain - Completed FlowHandlerTask thread for dpid: openflow:1