NIFI-12370 Fixed Distributed Map Cache Client Service Shutdown

[exceptionfactory]

Summary

NIFI-12370 Corrects the behavior of the DistributedMapCacheClientService to close the supporting Netty thread pool when disabling the Controller Service.

The resolution moves the creation of the Netty NioEventLoopGroup from the Channel Pool Factory to the calling DistributedCacheClient so that the closeChannelPool() method can close both the ChannelPool and the EventLoopGroup.

This correction can be verified using the DistributedMapCacheClientService and the DistributedMapCacheServer together with the PutDistributedMapCache Processor. It is necessary to run the Processor at least once to create new threads. The presence of created threads can be verified using jconsole or a thread dump. After stopping the Processor and disabling the DistributedMapCacheClientService, the threads are no longer present in the JVM.

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Build

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  • JDK 21

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[esecules]

Pulled the branch, can confirm it's fixed.