spring cloud version 2021.0.4 spring-boot version 2.6.11 spring-cloud-alibaba version 2021.0.5.0 spring-cloud-starter-loadbalancer 3.1.4 JDK version 1.8.0_181 我使用 nacos 的discoveryClient.getInstances 可以获取到服务清单， 但是我使用loadbalancer loadBalancerClient.choose 获取清单的时候直接报了个空指针。 请大佬指点一下，看了好几天迷茫了。 配置什么的检查了好多遍 应该没问题。
`java.lang.NullPointerException: null at java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:936) ~[na:1.8.0_181] Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException: Error has been observed at the following site(s): __checkpoint ⇢ org.springframework.cloud.gateway.filter.WeightCalculatorWebFilter [DefaultWebFilterChain] __checkpoint ⇢ HTTP GET "/provider/readDemo/3" [ExceptionHandlingWebHandler] Original Stack Trace: at java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:936) ~[na:1.8.0_181] at java.util.concurrent.ConcurrentHashMap.containsKey(ConcurrentHashMap.java:964) ~[na:1.8.0_181] at org.springframework.cloud.context.named.NamedContextFactory.getContext(NamedContextFactory.java:105) ~[spring-cloud-context-3.1.4.jar:3.1.4] at org.springframework.cloud.context.named.NamedContextFactory.getProvider(NamedContextFactory.java:179) ~[spring-cloud-context-3.1.4.jar:3.1.4] at org.springframework.cloud.context.named.ClientFactoryObjectProvider.delegate(ClientFactoryObjectProvider.java:115) ~[spring-cloud-context-3.1.4.jar:3.1.4] at org.springframework.cloud.context.named.ClientFactoryObjectProvider.getIfAvailable(ClientFactoryObjectProvider.java:64) ~[spring-cloud-context-3.1.4.jar:3.1.4] at com.alibaba.cloud.nacos.loadbalancer.NacosLoadBalancer.choose(NacosLoadBalancer.java:125) ~[spring-cloud-starter-alibaba-nacos-discovery-2021.0.5.0.jar:2021.0.5.0] at org.springframework.cloud.gateway.filter.ReactiveLoadBalancerClientFilter.choose(ReactiveLoadBalancerClientFilter.java:180) ~[spring-cloud-gateway-server-3.1.4.jar:3.1.4] at org.springframework.cloud.gateway.filter.ReactiveLoadBalancerClientFilter.filter(ReactiveLoadBalancerClientFilter.java:119) ~[spring-cloud-gateway-server-3.1.4.jar:3.1.4] at org.springframework.cloud.gateway.handler.FilteringWebHandler$GatewayFilterAdapter.filter(FilteringWebHandler.java:137) ~[spring-cloud-gateway-server-3.1.4.jar:3.1.4] at org.springframework.cloud.gateway.filter.OrderedGatewayFilter.filter(OrderedGatewayFilter.java:44) ~[spring-cloud-gateway-server-3.1.4.jar:3.1.4] at org.springframework.cloud.gateway.handler.FilteringWebHandler$DefaultGatewayFilterChain.lambda$filter$0(FilteringWebHandler.java:117) ~[spring-cloud-gateway-server-3.1.4.jar:3.1.4] at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:44) [reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) [reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) [reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.Mono.subscribe(Mono.java:4397) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.subscribeNext(MonoIgnoreThen.java:263) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoIgnoreThen.subscribe(MonoIgnoreThen.java:51) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) [reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) [reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) [reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.Mono.subscribe(Mono.java:4397) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.subscribeNext(MonoIgnoreThen.java:263) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoIgnoreThen.subscribe(MonoIgnoreThen.java:51) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:157) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxSwitchIfEmpty$SwitchIfEmptySubscriber.onNext(FluxSwitchIfEmpty.java:74) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoNext$NextSubscriber.onNext(MonoNext.java:82) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.innerNext(FluxConcatMap.java:282) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxConcatMap$ConcatMapInner.onNext(FluxConcatMap.java:863) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxMap$MapSubscriber.onNext(FluxMap.java:122) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxSwitchIfEmpty$SwitchIfEmptySubscriber.onNext(FluxSwitchIfEmpty.java:74) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.Operators$MonoSubscriber.complete(Operators.java:1816) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:151) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxMap$MapSubscriber.onNext(FluxMap.java:122) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoNext$NextSubscriber.onNext(MonoNext.java:82) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.innerNext(FluxConcatMap.java:282) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxConcatMap$ConcatMapInner.onNext(FluxConcatMap.java:863) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxOnErrorResume$ResumeSubscriber.onNext(FluxOnErrorResume.java:79) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoPeekTerminal$MonoTerminalPeekSubscriber.onNext(MonoPeekTerminal.java:180) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.Operators$MonoSubscriber.complete(Operators.java:1816) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoFilterWhen$MonoFilterWhenMain.onNext(MonoFilterWhen.java:149) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.Operators$ScalarSubscription.request(Operators.java:2398) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoFilterWhen$MonoFilterWhenMain.onSubscribe(MonoFilterWhen.java:112) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoJust.subscribe(MonoJust.java:55) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.Mono.subscribe(Mono.java:4397) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.drain(FluxConcatMap.java:451) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.onNext(FluxConcatMap.java:251) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxDematerialize$DematerializeSubscriber.onNext(FluxDematerialize.java:98) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxDematerialize$DematerializeSubscriber.onNext(FluxDematerialize.java:44) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxIterable$IterableSubscription.slowPath(FluxIterable.java:272) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxIterable$IterableSubscription.request(FluxIterable.java:230) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxDematerialize$DematerializeSubscriber.request(FluxDematerialize.java:127) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.onSubscribe(FluxConcatMap.java:236) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxDematerialize$DematerializeSubscriber.onSubscribe(FluxDematerialize.java:77) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:165) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:87) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.InternalFluxOperator.subscribe(InternalFluxOperator.java:62) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxDefer.subscribe(FluxDefer.java:54) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.Mono.subscribe(Mono.java:4397) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.drain(FluxConcatMap.java:451) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxConcatMap$ConcatMapImmediate.onSubscribe(FluxConcatMap.java:219) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:165) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.FluxIterable.subscribe(FluxIterable.java:87) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) [reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) [reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.Mono.subscribe(Mono.java:4397) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.subscribeNext(MonoIgnoreThen.java:263) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoIgnoreThen.subscribe(MonoIgnoreThen.java:51) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.core.publisher.MonoDeferContextual.subscribe(MonoDeferContextual.java:55) ~[reactor-core-3.4.22.jar:3.4.22] at reactor.netty.http.server.HttpServer$HttpServerHandle.onStateChange(HttpServer.java:967) ~[reactor-netty-http-1.0.22.jar:1.0.22] at reactor.netty.ReactorNetty$CompositeConnectionObserver.onStateChange(ReactorNetty.java:677) ~[reactor-netty-core-1.0.22.jar:1.0.22] at reactor.netty.transport.ServerTransport$ChildObserver.onStateChange(ServerTransport.java:478) ~[reactor-netty-core-1.0.22.jar:1.0.22] at reactor.netty.http.server.HttpServerOperations.onInboundNext(HttpServerOperations.java:570) ~[reactor-netty-http-1.0.22.jar:1.0.22] at reactor.netty.channel.ChannelOperationsHandler.channelRead(ChannelOperationsHandler.java:93) ~[reactor-netty-core-1.0.22.jar:1.0.22] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at reactor.netty.http.server.HttpTrafficHandler.channelRead(HttpTrafficHandler.java:214) ~[reactor-netty-http-1.0.22.jar:1.0.22] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:436) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:327) ~[netty-codec-4.1.79.Final.jar:4.1.79.Final] at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:299) ~[netty-codec-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.CombinedChannelDuplexHandler.channelRead(CombinedChannelDuplexHandler.java:251) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1410) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:919) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:166) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:722) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:658) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:584) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:496) ~[netty-transport-4.1.79.Final.jar:4.1.79.Final] at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:997) ~[netty-common-4.1.79.Final.jar:4.1.79.Final] at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) ~[netty-common-4.1.79.Final.jar:4.1.79.Final] at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30) ~[netty-common-4.1.79.Final.jar:4.1.79.Final] at java.lang.Thread.run(Thread.java:748) ~[na:1.8.0_181]
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