dubbo-filter

本文介绍了如何创建一个Dubbo过滤器模块,引入dubbo依赖,定义了一个@Activate的DubboInvokerFilter类,用于记录调用时间。然后在配置文件META-INF/dubbo下的org.apache.dubbo.rpc.Filter中注册该过滤器,并在其他项目中引入模块进行测试。

1、编写模块 dubbo-filter,引入 dubbo jar 包

<dependencies>
     <dependency>
         <groupId>org.apache.dubbo</groupId>
         <artifactId>dubbo</artifactId>
         <version>2.7.5</version>
     </dependency>
</dependencies>

2、编写 filter 类,按照规范

@Activate(group = {CommonConstants.CONSUMER,CommonConstants.PROVIDER})
public class DubboInvokerFilter implements Filter {
    @Override
    public Result invoke(Invoker<?> invoker, Invocation invocation) throws RpcException {
        long start = System.currentTimeMillis();
        try {
            return invoker.invoke(invocation);
        }finally {
            System.out.println("invoke time:" + (System.currentTimeMillis() - start) + "毫秒");
        }
    }
}

3、在配置文件中注册过滤器

在指定文件夹下创建指定文件名称的文件

包名:META-INF/dubbo

文件名:org.apache.dubbo.rpc.Filter

timerFilter=com.lagou.filter.DubboInvokerFilter

4、在 demo-base 中引入该过滤器模块,进行测试

代码: @DubboService public class ItemDubbo implements ItemClient { private ItemService itemService; @Override public List<ItemDTO> queryItemByIds(Collection<Long> ids){ if (ids == null || ids.isEmpty()) { return Collections.emptyList(); } List<ItemDTO> items = itemService.queryItemByIds(ids); return items != null ? items : Collections.emptyList(); } @Override public void deductStock(List<OrderDetailDTO> items) { itemService.deductStock(items); } } DCartApplication: 20:58:04:658 INFO 4236 --- [erverWorker-5-2] o.a.d.r.t.netty4.NettyChannelHandler : [DUBBO] The connection [id: 0x1c88a03e, L:/10.44.85.106:50052 - R:/10.44.85.106:4038] of 10.44.85.106:4038 -> 10.44.85.106:50052 is established., dubbo version: 3.3.0, current host: 10.44.85.106 20:58:04:661 DEBUG 4236 --- [erverWorker-5-2] .a.d.r.p.t.r.m.RestRequestHandlerMapping : [DUBBO] Received http request: ServletHttpRequestAdapter{method='GET', uri='/carts', contentType='null'}, dubbo version: 3.3.0, current host: 10.44.85.106 20:58:04:661 DEBUG 4236 --- [erverWorker-5-2] .r.p.t.r.m.DefaultRequestMappingRegistry : [DUBBO] Matched rest mapping=RequestMapping{name='CartControllerImpl#queryMyCarts', path=PathCondition{paths=[/carts]}, methods=MethodsCondition{methods=[GET]}}, method=MethodMeta{method=com.hmall.cartdubbo.controller.CartController.queryMyCarts(), service=CartControllerImpl@64aab3fd}, dubbo version: 3.3.0, current host: 10.44.85.106 20:58:04:661 DEBUG 4236 --- [erverWorker-5-2] .a.d.r.p.t.r.m.RestRequestHandlerMapping : [DUBBO] Content-type negotiate result: request='null', response='application/json', dubbo version: 3.3.0, current host: 10.44.85.106 20:58:04:662 DEBUG 4236 --- [:50052-thread-6] eataTransactionPropagationProviderFilter : [DUBBO] Server side xid in RpcContext[null], dubbo version: 3.3.0, current host: 10.44.85.106 坤坤invoke执行力! 20:58:04:665 DEBUG 4236 --- [:50052-thread-6] c.h.c.mapper.CartMapper.selectList : ==> Preparing: SELECT id,user_id,item_id,num,name,spec,price,image,create_time,update_time FROM cart WHERE (user_id = ?) 20:58:04:665 DEBUG 4236 --- [:50052-thread-6] c.h.c.mapper.CartMapper.selectList : ==> Parameters: 1(Long) 20:58:04:668 DEBUG 4236 --- [:50052-thread-6] c.h.c.mapper.CartMapper.selectList : <== Total: 5 20:58:04:669 DEBUG 4236 --- [:50052-thread-6] o.a.d.r.c.s.wrapper.ScopeClusterInvoker : [DUBBO] Performing remote call for method: queryItemByIds of service: com.hmall.apidubbo.client.ItemClient, dubbo version: 3.3.0, current host: 10.44.85.106 20:58:04:670 DEBUG 4236 --- [:50052-thread-6] eataTransactionPropagationConsumerFilter : [DUBBO] Client side xid in RootContext[null], dubbo version: 3.3.0, current host: 10.44.85.106 坤坤invoke执行力! 20:58:04:838 ERROR 4236 --- [:50052-thread-6] o.a.dubbo.rpc.filter.ExceptionFilter : [DUBBO] Got unchecked and undeclared exception which called by 10.44.85.106. service: com.hmall.cartdubbo.controller.CartController, method: queryMyCarts, exception: java.lang.NullPointerException: null, dubbo version: 3.3.0, current host: 10.44.85.106, error code: 5-36. This may be caused by , go to https://dubbo.apache.org/faq/5/36 to find instructions. java.lang.NullPointerException: null at com.hmall.itemdubbo.controller.ItemDubbo.queryItemByIds(ItemDubbo.java:23) ~[na:na] at com.hmall.itemdubbo.controller.ItemDubboDubboWrap0.invokeMethod(ItemDubboDubboWrap0.java) ~[na:na] at org.apache.dubbo.rpc.proxy.javassist.JavassistProxyFactory$1.doInvoke(JavassistProxyFactory.java:89) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.proxy.AbstractProxyInvoker.invoke(AbstractProxyInvoker.java:100) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.config.invoker.DelegateProviderMetaDataInvoker.invoke(DelegateProviderMetaDataInvoker.java:55) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.InvokerWrapper.invoke(InvokerWrapper.java:56) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.ClassLoaderCallbackFilter.invoke(ClassLoaderCallbackFilter.java:38) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.HttpContextCallbackFilter.invoke(HttpContextCallbackFilter.java:37) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.rest.filter.RestFilterAdapter.invoke(RestFilterAdapter.java:38) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at com.alibaba.dubbo.rpc.Invoker$CompatibleInvoker.invoke(Invoker.java:77) ~[dubbo-3.3.0.jar:3.3.0] at io.seata.integration.dubbo.alibaba.AlibabaDubboTransactionPropagationFilter.invoke(AlibabaDubboTransactionPropagationFilter.java:45) ~[seata-all-2.0.0.jar:2.0.0] at com.alibaba.dubbo.rpc.Filter.invoke(Filter.java:34) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at com.hmall.commondubbo.filter.UserInfoDubboFilter.invoke(UserInfoDubboFilter.java:40) ~[classes/:na] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.dubbo.filter.TraceFilter.invoke(TraceFilter.java:80) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.TimeoutFilter.invoke(TimeoutFilter.java:45) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.seata.SeataTransactionPropagationProviderFilter.invoke(SeataTransactionPropagationProviderFilter.java:66) ~[dubbo-filter-seata-1.0.2.jar:1.0.2] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.monitor.support.MonitorFilter.invoke(MonitorFilter.java:109) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.ExceptionFilter.invoke(ExceptionFilter.java:55) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.AccessLogFilter.invoke(AccessLogFilter.java:120) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.GenericFilter.invoke(GenericFilter.java:222) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.HttpContextFilter.invoke(HttpContextFilter.java:50) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.ClassLoaderFilter.invoke(ClassLoaderFilter.java:54) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.EchoFilter.invoke(EchoFilter.java:41) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.metrics.filter.MetricsFilter.invoke(MetricsFilter.java:86) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.metrics.filter.MetricsProviderFilter.invoke(MetricsProviderFilter.java:37) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.ProfilerServerFilter.invoke(ProfilerServerFilter.java:66) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.ContextFilter.invoke(ContextFilter.java:191) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CallbackRegistrationInvoker.invoke(FilterChainBuilder.java:197) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.AbstractServerCallListener.invoke(AbstractServerCallListener.java:69) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.UnaryServerCallListener.onComplete(UnaryServerCallListener.java:50) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.http2.GenericHttp2ServerTransportListener$Http2StreamingDecodeListener.onClose(GenericHttp2ServerTransportListener.java:201) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.remoting.http12.message.DefaultListeningDecoder.close(DefaultListeningDecoder.java:47) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.remoting.http12.message.StreamingDecoder$DefaultFragmentListener.onClose(StreamingDecoder.java:60) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.remoting.http12.message.LengthFieldStreamingDecoder.deliver(LengthFieldStreamingDecoder.java:135) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.remoting.http12.message.LengthFieldStreamingDecoder.close(LengthFieldStreamingDecoder.java:81) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.http2.GenericHttp2ServerTransportListener.onDataCompletion(GenericHttp2ServerTransportListener.java:143) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.http2.GenericHttp2ServerTransportListener.onDataCompletion(GenericHttp2ServerTransportListener.java:49) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.AbstractServerTransportListener.doOnData(AbstractServerTransportListener.java:187) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.AbstractServerTransportListener.lambda$onData$1(AbstractServerTransportListener.java:171) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.common.threadpool.serial.SerializingExecutor.run(SerializingExecutor.java:105) ~[dubbo-3.3.0.jar:3.3.0] at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) ~[na:na] at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) ~[na:na] at org.apache.dubbo.common.threadlocal.InternalRunnable.run(InternalRunnable.java:39) ~[dubbo-3.3.0.jar:3.3.0] at java.base/java.lang.Thread.run(Thread.java:829) ~[na:na] 20:58:04:841 DEBUG 4236 --- [:50052-thread-6] .d.r.h.AbstractServerHttpChannelObserver : [DUBBO] Http response body sent: '{"status":"500"}' by [org.apache.dubbo.remoting.http12.netty4.h1.NettyHttp1Channel@59140dd4], dubbo version: 3.3.0, current host: 10.44.85.106 20:58:04:842 DEBUG 4236 --- [:50052-thread-6] .d.r.h.AbstractServerHttpChannelObserver : [DUBBO] Http response headers sent: NettyHttp1HttpHeaders{headers=DefaultHttpHeaders[:status: 500, content-type: application/json, alt-svc: h2=":50052", content-length: 16]}, dubbo version: 3.3.0, current host: 10.44.85.106 DItemApplication: 20:58:04:802 ERROR 12688 --- [:50053-thread-2] o.a.dubbo.rpc.filter.ExceptionFilter : [DUBBO] Got unchecked and undeclared exception which called by 10.44.85.106. service: com.hmall.apidubbo.client.ItemClient, method: queryItemByIds, exception: java.lang.NullPointerException: null, dubbo version: 3.3.0, current host: 10.44.85.106, error code: 5-36. This may be caused by , go to https://dubbo.apache.org/faq/5/36 to find instructions. java.lang.NullPointerException: null at com.hmall.itemdubbo.controller.ItemDubbo.queryItemByIds(ItemDubbo.java:23) ~[classes/:na] at com.hmall.itemdubbo.controller.ItemDubboDubboWrap0.invokeMethod(ItemDubboDubboWrap0.java) ~[classes/:na] at org.apache.dubbo.rpc.proxy.javassist.JavassistProxyFactory$1.doInvoke(JavassistProxyFactory.java:89) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.proxy.AbstractProxyInvoker.invoke(AbstractProxyInvoker.java:100) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.config.invoker.DelegateProviderMetaDataInvoker.invoke(DelegateProviderMetaDataInvoker.java:55) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.InvokerWrapper.invoke(InvokerWrapper.java:56) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.ClassLoaderCallbackFilter.invoke(ClassLoaderCallbackFilter.java:38) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.HttpContextCallbackFilter.invoke(HttpContextCallbackFilter.java:37) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.rest.filter.RestFilterAdapter.invoke(RestFilterAdapter.java:38) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at com.alibaba.dubbo.rpc.Invoker$CompatibleInvoker.invoke(Invoker.java:77) ~[dubbo-3.3.0.jar:3.3.0] at io.seata.integration.dubbo.alibaba.AlibabaDubboTransactionPropagationFilter.invoke(AlibabaDubboTransactionPropagationFilter.java:45) ~[seata-all-2.0.0.jar:2.0.0] at com.alibaba.dubbo.rpc.Filter.invoke(Filter.java:34) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at com.hmall.commondubbo.filter.UserInfoDubboFilter.invoke(UserInfoDubboFilter.java:40) ~[classes/:na] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.dubbo.filter.TraceFilter.invoke(TraceFilter.java:80) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.TimeoutFilter.invoke(TimeoutFilter.java:45) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.seata.SeataTransactionPropagationProviderFilter.invoke(SeataTransactionPropagationProviderFilter.java:66) ~[dubbo-filter-seata-1.0.2.jar:1.0.2] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.monitor.support.MonitorFilter.invoke(MonitorFilter.java:109) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.ExceptionFilter.invoke(ExceptionFilter.java:55) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.AccessLogFilter.invoke(AccessLogFilter.java:120) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.GenericFilter.invoke(GenericFilter.java:222) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.HttpContextFilter.invoke(HttpContextFilter.java:50) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.ClassLoaderFilter.invoke(ClassLoaderFilter.java:54) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.EchoFilter.invoke(EchoFilter.java:41) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.metrics.filter.MetricsFilter.invoke(MetricsFilter.java:86) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.metrics.filter.MetricsProviderFilter.invoke(MetricsProviderFilter.java:37) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.ProfilerServerFilter.invoke(ProfilerServerFilter.java:66) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.filter.ContextFilter.invoke(ContextFilter.java:191) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CopyOfFilterChainNode.invoke(FilterChainBuilder.java:349) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.cluster.filter.FilterChainBuilder$CallbackRegistrationInvoker.invoke(FilterChainBuilder.java:197) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.AbstractServerCallListener.invoke(AbstractServerCallListener.java:69) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.UnaryServerCallListener.onComplete(UnaryServerCallListener.java:50) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.http2.GenericHttp2ServerTransportListener$Http2StreamingDecodeListener.onClose(GenericHttp2ServerTransportListener.java:201) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.remoting.http12.message.DefaultListeningDecoder.close(DefaultListeningDecoder.java:47) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.remoting.http12.message.StreamingDecoder$DefaultFragmentListener.onClose(StreamingDecoder.java:60) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.remoting.http12.message.LengthFieldStreamingDecoder.deliver(LengthFieldStreamingDecoder.java:135) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.remoting.http12.message.LengthFieldStreamingDecoder.close(LengthFieldStreamingDecoder.java:81) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.http2.GenericHttp2ServerTransportListener.onDataCompletion(GenericHttp2ServerTransportListener.java:143) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.http2.GenericHttp2ServerTransportListener.onDataCompletion(GenericHttp2ServerTransportListener.java:49) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.AbstractServerTransportListener.doOnData(AbstractServerTransportListener.java:187) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.rpc.protocol.tri.h12.AbstractServerTransportListener.lambda$onData$1(AbstractServerTransportListener.java:171) ~[dubbo-3.3.0.jar:3.3.0] at org.apache.dubbo.common.threadpool.serial.SerializingExecutor.run(SerializingExecutor.java:105) ~[dubbo-3.3.0.jar:3.3.0] at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) ~[na:na] at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) ~[na:na] at org.apache.dubbo.common.threadlocal.InternalRunnable.run(InternalRunnable.java:39) ~[dubbo-3.3.0.jar:3.3.0] at java.base/java.lang.Thread.run(Thread.java:829) ~[na:na]
最新发布
08-11
从你提供的代码和日志来看,问题依然出在 `ItemDubbo.queryItemByIds()` 方法中,抛出了 `NullPointerException`。我们来深入分析并提出解决方案。 --- ### ✅ 问题定位 代码如下: ```java @DubboService public class ItemDubbo implements ItemClient { private ItemService itemService; @Override public List<ItemDTO> queryItemByIds(Collection<Long> ids){ if (ids == null || ids.isEmpty()) { return Collections.emptyList(); } List<ItemDTO> items = itemService.queryItemByIds(ids); return items != null ? items : Collections.emptyList(); } } ``` 日志显示错误发生在: ``` java.lang.NullPointerException: null at com.hmall.itemdubbo.controller.ItemDubbo.queryItemByIds(ItemDubbo.java:23) ``` **第 23 行是:** ```java List<ItemDTO> items = itemService.queryItemByIds(ids); ``` --- ### ❌ 问题原因 `itemService` 是 `null`,说明没有被 Spring 正确注入。 尽管类上有 `@DubboService` 注解,但没有使用 `@Autowired` 或构造函数注入 `ItemService`。 --- ### ✅ 解决方案 #### ✅ 方法一:添加 `@Autowired` 注解 修改代码如下: ```java @DubboService public class ItemDubbo implements ItemClient { @Autowired private ItemService itemService; @Override public List<ItemDTO> queryItemByIds(Collection<Long> ids){ if (ids == null || ids.isEmpty()) { return Collections.emptyList(); } List<ItemDTO> items = itemService.queryItemByIds(ids); return items != null ? items : Collections.emptyList(); } } ``` #### ✅ 方法二:使用构造函数注入(推荐) ```java @DubboService public class ItemDubbo implements ItemClient { private final ItemService itemService; @Autowired public ItemDubbo(ItemService itemService) { this.itemService = itemService; } @Override public List<ItemDTO> queryItemByIds(Collection<Long> ids){ if (ids == null || ids.isEmpty()) { return Collections.emptyList(); } List<ItemDTO> items = itemService.queryItemByIds(ids); return items != null ? items : Collections.emptyList(); } } ``` --- ### ✅ 验证建议 1. **重启服务**,确保 Spring 容器正确加载。 2. **检查日志**,确认 `ItemDubbo` 是否成功注入 `ItemService`。 3. **调用接口 `/carts`**,验证是否还抛出 `NullPointerException`。 --- ### ✅ 总结 - **根本原因**:`ItemService` 没有被注入,导致调用时报空指针。 - **解决方法**:为 `ItemService` 添加 `@Autowired` 注解或使用构造函数注入。 - **建议实践**:优先使用构造函数注入,避免字段注入导致的测试困难和潜在的空指针问题。 ---
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