问题

eureka 使用 RestTemplate 调用服务时，出现如下错误。

2019-12-18 17:32:23.129 ERROR 12204 --- [nio-9913-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.web.client.ResourceAccessException: I/O error on GET request for "http://wbw-stu-user-service/user/getAll": wbw-stu-user-service; nested exception is java.net.UnknownHostException: wbw-stu-user-service] with root causejava.net.UnknownHostException: wbw-stu-user-serviceat java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:184) ~[na:1.8.0_191]at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172) ~[na:1.8.0_191]at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392) ~[na:1.8.0_191]at java.net.Socket.connect(Socket.java:589) ~[na:1.8.0_191]at java.net.Socket.connect(Socket.java:538) ~[na:1.8.0_191]at sun.net.NetworkClient.doConnect(NetworkClient.java:180) ~[na:1.8.0_191]at sun.net.www.http.HttpClient.openServer(HttpClient.java:463) ~[na:1.8.0_191]at sun.net.www.http.HttpClient.openServer(HttpClient.java:558) ~[na:1.8.0_191]at sun.net.www.http.HttpClient.<init>(HttpClient.java:242) ~[na:1.8.0_191]at sun.net.www.http.HttpClient.New(HttpClient.java:339) ~[na:1.8.0_191]at sun.net.www.http.HttpClient.New(HttpClient.java:357) ~[na:1.8.0_191]at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:1220) ~[na:1.8.0_191]at sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1156) ~[na:1.8.0_191]at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1050) ~[na:1.8.0_191]at sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:984) ~[na:1.8.0_191]at org.springframework.http.client.SimpleBufferingClientHttpRequest.executeInternal(SimpleBufferingClientHttpRequest.java:76) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.http.client.AbstractBufferingClientHttpRequest.executeInternal(AbstractBufferingClientHttpRequest.java:48) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.http.client.AbstractClientHttpRequest.execute(AbstractClientHttpRequest.java:53) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:723) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:680) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.client.RestTemplate.getForEntity(RestTemplate.java:359) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at cn.wbw.study.controller.ProductController.list(ProductController.java:27) ~[classes/:na]at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_191]at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_191]at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_191]at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_191]at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102) ~[spring-webmvc-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:877) ~[spring-webmvc-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:783) ~[spring-webmvc-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991) ~[spring-webmvc-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925) ~[spring-webmvc-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974) ~[spring-webmvc-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:866) ~[spring-webmvc-5.0.7.RELEASE.jar:5.0.7.RELEASE]at javax.servlet.http.HttpServlet.service(HttpServlet.java:635) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851) ~[spring-webmvc-5.0.7.RELEASE.jar:5.0.7.RELEASE]at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-embed-websocket-8.5.31.jar:8.5.31]at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:158) ~[spring-boot-actuator-2.0.3.RELEASE.jar:2.0.3.RELEASE]at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.filterAndRecordMetrics(WebMvcMetricsFilter.java:126) ~[spring-boot-actuator-2.0.3.RELEASE.jar:2.0.3.RELEASE]at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:111) ~[spring-boot-actuator-2.0.3.RELEASE.jar:2.0.3.RELEASE]at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.springframework.boot.actuate.web.trace.servlet.HttpTraceFilter.doFilterInternal(HttpTraceFilter.java:90) ~[spring-boot-actuator-2.0.3.RELEASE.jar:2.0.3.RELEASE]at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:109) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-5.0.7.RELEASE.jar:5.0.7.RELEASE]at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) ~[tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:496) [tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) [tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) [tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803) [tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:790) [tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1468) [tomcat-embed-core-8.5.31.jar:8.5.31]at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.31.jar:8.5.31]at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_191]at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_191]at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.31.jar:8.5.31]at java.lang.Thread.run(Thread.java:748) [na:1.8.0_191]

原因

错误提示是未识别服务地址。

使用 RestTemplate 时需要注册，配置错误是找不到服务列表的，所以出现此错误，同时，服务调用服务名称要和eureka的应用名称一致。

server:port: 9913
spring:application:name: wbw-stu-product-service
logging:file: logs/${spring.application.name}.logeureka:instance:ip-address: trueclient:register-with-eureka: true#    获取已注册的服务fetch-registry: trueservice-url:defaultZone: http://localhost:9911/eureka#    同步时间秒数registry-fetch-interval-seconds: 30

import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.stereotype.Component;
import org.springframework.web.client.RestTemplate;/*** 模板远程** @author wbw* @date 2019/12/18 17:18*/
@Component
@Configuration
public class ServiceTemplate {@Bean(value = "restTemplate")@LoadBalancedpublic RestTemplate restTemplate() {return new RestTemplate();}
}

使用 RestTemplate

@RestController
@RequestMapping("/product")
public class ProductController {@Autowired@Qualifier(value = "restTemplate")private RestTemplate template;@RequestMapping("/user/list")public Object list() {return template.getForEntity("http://WBW-STU-USER-SERVICE/user/getAll", List.class).getBody();}
}

@LoadBalanced注解的作用

1.开启负载均衡的功能：开启负载均衡很简单，只需要在RestTemplate的bean上再添加一个@LoadBalanced注解即可。

2.由于加了@LoadBalanced注解，使用RestTemplateCustomizer对所有标注了@LoadBalanced的RestTemplate Bean添加了一个LoadBalancerInterceptor拦截器。利用RestTempllate的拦截器，spring可以对restTemplate bean进行定制，加入loadbalance拦截器进行ip:port的替换，也就是将请求的地址中的服务逻辑名转为具体的服务地址。

3、另外当spring容器中有多个相同类型的bean的时候，可以通过@LoadBalanced来进行区分，以便在注入的时候明确表明你要注入具体的哪个bean,消除歧义。

4、@LoadBalanced就是一个修饰符，和@Qualifier一样，标注了@Qualifier("invalid")的user bean都会自动注入到Bean、List和Map中去。

SpringCloud RestTemplate | java.net.UnknownHostException: xxx相关推荐

Docker部署微服务时Springcloud网关报错 java.net.UnknownHostException: xxx: Name or service not known
文章目录一.问题二.原因三.解决办法一.问题 eureka.gateway 和微服务应用部署好后用网关访问应用时报错 java.net.UnknownHostException: 235e ...
Spring Cloud Alibaba 服务消费者调用 nacos 服务报错：java.net.UnknownHostException: xxx
目录 1. 服务消费者启动类 1.1. 服务消费者 controller 2. 服务提供者启动类 2.1. 服务提供者 controller 3. 服务报错 4. nacos 信息 5. 解决思路 5 ...
linux,java.net.UnknownHostException:XXX:XXX: Name or service not known
vi /etc/hosts 127.0.0.1 iZuf6cu3sus3ygds9nmswzZ XXX 当前主机名称添加以后的结果 127.0.0.1 iZuf6cu3sus3ygds9nmswz ...
UnknownHostException: xxx异常
今天出现个问题,解决了半天,说到底还是自己踩的坑太少太年轻,自己太菜.这里就简单的跟大家分享一下. 异常为:java.net.UnknownHostException: xxx: at org.apa ...
Spring cloud Eureka consumer 调用 provider ERROR:java.net.UnknownHostException: XXX-PAYMENT-SERVICE
日常踩坑不是在填坑,那就是在去挖坑的路上控制台详情: 2020-08-01 10:48:02.709 ERROR 31608 --- [p-nio-80-exec-1] o.a.c.c.C.[.[ ...
com.sun.jersey.api.client.ClientHandlerException: java.net.UnknownHostException: eureka8001
最近启动SpringCloud 微服务项目客户端启动项目时报了下面的错误: 2021-01-08 16:47:19.682 ERROR 29172 --- [ restartedMain] c.n.d ...
java.net.UnknownHostException异常处理
1.问题描述最近迁移环境,在Linux系统下部署Java产品的应用,后台报出如下异常,系统报找不到名为"xxx-houtai1"的主机: 1 java.net.UnknownHo ...
java.net.UnknownHostException 请求地址出现异常问题
java.net.UnknownHostException: www.xxx.cn: Temporary failure in name resolution 就是项目调用三方地址出现问题,记录一下 ...
java.net.UnknownHostException: CLOUD-XXXXX-SERVICE 问题错误报错。。。
1. 问题原因,由于你自己的微服务提供者设置了集群你通过访问注册中心的注册名如: CLOUD-XXXXX-SERVICE 注册中心并不知道你要访问你集群下面的哪一个服务,所以报错. 2. 问题报 ...

SpringCloud RestTemplate | java.net.UnknownHostException: xxx

问题

原因

使用 RestTemplate

@LoadBalanced注解的作用

SpringCloud RestTemplate | java.net.UnknownHostException: xxx相关推荐

最新文章

热门文章