Root Cause of Curator Exception

Question

My Spring Boot Application threw this exception during runtime and crashed ? Can anyone explain me the reason.

2023-02-16 17:03:15,576 [Curator-TreeCache-1] [45] org.apache.curator.framework.recipes.cache.TreeCache:827 -  java.lang.IllegalStateException: Shutdown in progress       
   at org.springframework.util.Assert.state(Assert.java:76 undefined)       
   at org.springframework.boot.SpringApplicationShutdownHook.assertNotInProgress(SpringApplicationShutdownHook.java:166 undefined)       
   at org.springframework.boot.SpringApplicationShutdownHook.registerApplicationContext(SpringApplicationShutdownHook.java:75 undefined)       
   at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:413 undefined)       
   at org.springframework.boot.SpringApplication.run(SpringApplication.java:303 undefined)       
   at org.springframework.boot.builder.SpringApplicationBuilder.run(SpringApplicationBuilder.java:164 undefined)       
   at org.springframework.cloud.context.refresh.LegacyContextRefresher.addConfigFilesToEnvironment(LegacyContextRefresher.java:78 undefined)       
   at org.springframework.cloud.context.refresh.LegacyContextRefresher.updateEnvironment(LegacyContextRefresher.java:56 undefined)       
   at org.springframework.cloud.context.refresh.ContextRefresher.refreshEnvironment(ContextRefresher.java:101 undefined)       
   at org.springframework.cloud.context.ContextRefresher.refresh.refresh(ContextRefresher.java:94 undefined)       
   at org.springframework.cloud.endpoint.event.RefreshEventListener.handle(RefreshEventListener.java:72 undefined)       
   at org.springframework.cloud.endpoint.event.RefreshEventListener.onApplicationEvent(RefreshEventListener.java:61 undefined)       
   at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:176 undefined)       
   at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:169 undefined)       
   at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:143 undefined)       
   at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:421 undefined)       
   at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:378 undefined)       
   at org.springframework.cloud.zookeeper.config.ConfigWatcher.childEvent(ConfigWatcher.java:118 undefined)       
   at org.apache.curator.framework.recipes.cache.TreeCache.lambda$callListeners$0(TreeCache.java:810 undefined)       
   at org.apache.curator.framework.listen.MappingListenerManager.lambda$forEach$0(MappingListenerManager.java:92 undefined)       
   at org.apache.curator.framework.listen.MappingListenerManager.forEach(MappingListenerManager.java:89 undefined)       
   at org.apache.curator.framework.listen.StandardListenerManager.forEach(StandardListenerManager.java:89 undefined)       
   at org.apache.curator.framework.recipes.cache.TreeCache.callListeners(TreeCache.java:806 undefined)       
   at org.apache.curator.framework.recipes.cache.TreeCache.access$1800(TreeCache.java:78 undefined)       
   at org.apache.curator.framework.recipes.cache.TreeCache$2.run(TreeCache.java:908 undefined)       
   at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539 undefined)       
   at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264 undefined)       
   at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136 undefined)       
   at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635 undefined)       
   at java.base/java.lang.Thread.run(Thread.java:833 undefined)

Here is the another exception log just before the previous one.

2023-02-16 16:01:11,320 [main-EventThread] [17] org.apache.curator.framework.imps.CuratorFrameworkImpl:699 - Background exception was not retry-able or retry gave up java.lang.NullPointerException: Cannot invoke "java.net.InetAddress.getHostAddress()" because the return value of "java.net.InetSocketAddress.getAddress()" is null at org.apache.curator.utils.Compatibility.getHostAddress(Compatibility.java:116) at org.apache.curator.framework.imps.EnsembleTracker.configToConnectionString(EnsembleTracker.java:185) at org.apache.curator.framework.imps.EnsembleTracker.processConfigData(EnsembleTracker.java:206) at org.apache.curator.framework.imps.EnsembleTracker.access$300(EnsembleTracker.java:50) at org.apache.curator.framework.imps.EnsembleTracker$2.processResult(EnsembleTracker.java:150) at org.apache.curator.framework.imps.CuratorFrameworkImpl.sendToBackgroundCallback(CuratorFrameworkImpl.java:892) at org.apache.curator.framework.imps.CuratorFrameworkImpl.processBackgroundOperation(CuratorFrameworkImpl.java:649) at org.apache.curator.framework.imps.WatcherRemovalFacade.processBackgroundOperation(WatcherRemovalFacade.java:152) at org.apache.curator.framework.imps.GetConfigBuilderImpl$2.processResult(GetConfigBuilderImpl.java:222) at org.apache.zookeeper.ClientCnxn$EventThread.processEvent(ClientCnxn.java:634) at org.apache.zookeeper.ClientCnxn$EventThread.run(ClientCnxn.java:553