在我的Angular 2应用程序中，我有一个通信服务，我用它来广播其他角度组件的消息。
2016-07-21 10:35:24.912 INFO 1455 --- [ restartedMain] a.b.p.App2App : Started App2App in 14.944 seconds (JVM running for 15.912)
2016-07-21 10:35:24.913 INFO 1455 --- [ restartedMain] a.b.p.App2App :
----------------------------------------------------------
Application 'app2' is running! Access URLs:
Local: http://127.0.0.1:8081
External: http://192.168.1.104:8081
----------------------------------------------------------
2016-07-21 10:35:24.913 INFO 1455 --- [ restartedMain] a.b.p.App2App :
----------------------------------------------------------
Config Server: Connected to the JHipster Registry running in Docker
----------------------------------------------------------
2016-07-21 10:35:24.915 DEBUG 1455 --- [nfoReplicator-0] s.n.www.protocol.http.HttpURLConnection : sun.net.www.MessageHeader@33e72d406 pairs: {GET /config/application/prod/master HTTP/1.1: null}{Accept: application/json, application/*+json}{Authorization: Basic YWRtaW46YWRtaW4=}{User-Agent: Java/1.8.0_65}{Host: localhost:8761}{Connection: keep-alive}
2016-07-21 10:35:25.057 DEBUG 1455 --- [nfoReplicator-0] s.n.www.protocol.http.HttpURLConnection : sun.net.www.MessageHeader@d6320d811 pairs: {null: HTTP/1.1 200 OK}{Server: Apache-Coyote/1.1}{X-Content-Type-Options: nosniff}{X-XSS-Protection: 1; mode=block}{Cache-Control: no-cache, no-store, max-age=0, must-revalidate}{Pragma: no-cache}{Expires: 0}{X-Application-Context: jhipster-registry:dev,native:8761}{Content-Type: application/json;charset=UTF-8}{Transfer-Encoding: chunked}{Date: Thu, 21 Jul 2016 13:35:24 GMT}
2016-07-21 10:35:25.058 INFO 1455 --- [nfoReplicator-0] com.netflix.discovery.DiscoveryClient : DiscoveryClient_APP2/app2:cddc722884843f95abdcf09d4996623d: registering service...
2016-07-21 10:35:25.059 ERROR 1455 --- [nfoReplicator-0] c.n.d.s.t.d.RedirectingEurekaHttpClient : Request execution error
com.sun.jersey.api.client.ClientHandlerException: java.net.UnknownHostException: registry
at com.sun.jersey.client.apache4.ApacheHttpClient4Handler.handle(ApacheHttpClient4Handler.java:187)
at com.sun.jersey.api.client.filter.GZIPContentEncodingFilter.handle(GZIPContentEncodingFilter.java:123)
at com.netflix.discovery.EurekaIdentityHeaderFilter.handle(EurekaIdentityHeaderFilter.java:27)
at com.sun.jersey.api.client.Client.handle(Client.java:652)
at com.sun.jersey.api.client.WebResource.handle(WebResource.java:682)
at com.sun.jersey.api.client.WebResource.access$200(WebResource.java:74)
at com.sun.jersey.api.client.WebResource$Builder.post(WebResource.java:570)
at com.netflix.discovery.shared.transport.jersey.AbstractJerseyEurekaHttpClient.register(AbstractJerseyEurekaHttpClient.java:56)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator$1.execute(EurekaHttpClientDecorator.java:59)
at com.netflix.discovery.shared.transport.decorator.MetricsCollectingEurekaHttpClient.execute(MetricsCollectingEurekaHttpClient.java:73)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.register(EurekaHttpClientDecorator.java:56)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator$1.execute(EurekaHttpClientDecorator.java:59)
at com.netflix.discovery.shared.transport.decorator.RedirectingEurekaHttpClient.executeOnNewServer(RedirectingEurekaHttpClient.java:118)
at com.netflix.discovery.shared.transport.decorator.RedirectingEurekaHttpClient.execute(RedirectingEurekaHttpClient.java:79)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.register(EurekaHttpClientDecorator.java:56)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator$1.execute(EurekaHttpClientDecorator.java:59)
at com.netflix.discovery.shared.transport.decorator.RetryableEurekaHttpClient.execute(RetryableEurekaHttpClient.java:119)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.register(EurekaHttpClientDecorator.java:56)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator$1.execute(EurekaHttpClientDecorator.java:59)
at com.netflix.discovery.shared.transport.decorator.SessionedEurekaHttpClient.execute(SessionedEurekaHttpClient.java:77)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.register(EurekaHttpClientDecorator.java:56)
at com.netflix.discovery.DiscoveryClient.register(DiscoveryClient.java:810)
at com.netflix.discovery.InstanceInfoReplicator.run(InstanceInfoReplicator.java:103)
at com.netflix.discovery.InstanceInfoReplicator$1.run(InstanceInfoReplicator.java:87)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.net.UnknownHostException: registry
at java.net.InetAddress.getAllByName0(InetAddress.java:1280)
at java.net.InetAddress.getAllByName(InetAddress.java:1192)
at java.net.InetAddress.getAllByName(InetAddress.java:1126)
at org.apache.http.impl.conn.SystemDefaultDnsResolver.resolve(SystemDefaultDnsResolver.java:45)
at org.apache.http.impl.conn.DefaultClientConnectionOperator.resolveHostname(DefaultClientConnectionOperator.java:259)
at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:159)
at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:144)
at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:131)
at org.apache.http.impl.client.DefaultRequestDirector.tryConnect(DefaultRequestDirector.java:611)
at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:446)
at org.apache.http.impl.client.AbstractHttpClient.doExecute(AbstractHttpClient.java:882)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:117)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:55)
at com.sun.jersey.client.apache4.ApacheHttpClient4Handler.handle(ApacheHttpClient4Handler.java:173)
... 30 common frames omitted
2016-07-21 10:35:25.059 WARN 1455 --- [nfoReplicator-0] c.n.d.s.t.d.RetryableEurekaHttpClient : Request execution failure
2016-07-21 10:35:25.060 WARN 1455 --- [nfoReplicator-0] com.netflix.discovery.DiscoveryClient : DiscoveryClient_APP2/app2:cddc722884843f95abdcf09d4996623d - registration failed Cannot execute request on any known server
com.netflix.discovery.shared.transport.TransportException: Cannot execute request on any known server
at com.netflix.discovery.shared.transport.decorator.RetryableEurekaHttpClient.execute(RetryableEurekaHttpClient.java:111)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.register(EurekaHttpClientDecorator.java:56)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator$1.execute(EurekaHttpClientDecorator.java:59)
at com.netflix.discovery.shared.transport.decorator.SessionedEurekaHttpClient.execute(SessionedEurekaHttpClient.java:77)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.register(EurekaHttpClientDecorator.java:56)
at com.netflix.discovery.DiscoveryClient.register(DiscoveryClient.java:810)
at com.netflix.discovery.InstanceInfoReplicator.run(InstanceInfoReplicator.java:103)
at com.netflix.discovery.InstanceInfoReplicator$1.run(InstanceInfoReplicator.java:87)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
2016-07-21 10:35:25.060 WARN 1455 --- [nfoReplicator-0] c.n.discovery.InstanceInfoReplicator : There was a problem with the instance info replicator
com.netflix.discovery.shared.transport.TransportException: Cannot execute request on any known server
at com.netflix.discovery.shared.transport.decorator.RetryableEurekaHttpClient.execute(RetryableEurekaHttpClient.java:111)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.register(EurekaHttpClientDecorator.java:56)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator$1.execute(EurekaHttpClientDecorator.java:59)
at com.netflix.discovery.shared.transport.decorator.SessionedEurekaHttpClient.execute(SessionedEurekaHttpClient.java:77)
at com.netflix.discovery.shared.transport.decorator.EurekaHttpClientDecorator.register(EurekaHttpClientDecorator.java:56)
at com.netflix.discovery.DiscoveryClient.register(DiscoveryClient.java:810)
at com.netflix.discovery.InstanceInfoReplicator.run(InstanceInfoReplicator.java:103)
at com.netflix.discovery.InstanceInfoReplicator$1.run(InstanceInfoReplicator.java:87)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
这很有效，但有时我知道我想发送哪个组件的消息：RxJs可以向特定的观察者发送消息吗？
答案 0 :(得分：1)
Observables意味着与Observers分离，因此如果您希望这样做，则无法通过命名查找来实现此目的。话虽这么说，您可以使用filter进行可选的过滤操作。
//In a consumer of your service
communicationService.broadcast$
//Will allow through events based on an optional field
.filter(({name}) => !name || name === 'component1')
.subscribe(x => /**/);