spring?cloud中Feign導入jar失敗的問題及解決方案

更新時間：2022年03月01日 11:16:46 作者：qq_33868430

這篇文章主要介紹了spring?cloud中Feign導入jar失敗的問題及解決方案，具有很好的參考價值，希望對大家有所幫助。如有錯誤或未考慮完全的地方，望不吝賜教

Feign導入jar失敗的問題

網上很多人在使用的feign時在pom.xml中填寫的是

? ?<dependency>?
? ? ? <groupId>org.springframework.cloud</groupId>?
? ? ? <artifactId>spring-cloud-starter-feign</artifactId>?
? ? </dependency>

但是在我個人的使用過程中沒能成功，像上面填好后一直報錯，說沒有指定版本，后來我有百度看是怎么回事：

?? ?<dependency>?
? ? ? <groupId>org.springframework.cloud</groupId>?
? ? ? <artifactId>spring-cloud-starter-feign</artifactId>?
? ? ? <version>1.3.1.RELEASE</version>?
? ? </dependency>

變成這個有版本號的了，以為成功了，準備寫@FeignClient發(fā)現沒有這個標簽，這下把我玩夠了，又在百度上找問題所在。

有的說是可能沒有下載完成導致的需要重新導入，搞了好久都沒有解決。最后我嘗試了最笨的方法，修改版本號看行不行，結果行了，把我玩夠了。下面這個在pom.xml 中導入就么有問題。

?? ?<dependency>?
? ? ? <groupId>org.springframework.cloud</groupId>?
? ? ? <artifactId>spring-cloud-starter-feign</artifactId>?
? ? ? <version>1.4.1.RELEASE</version>?
? ? </dependency>

經過自己在學習中發(fā)現

用以下的方式也能夠完美導入feign

? ? ? ? <dependency>
?? ??? ??? ?<groupId>org.springframework.cloud</groupId>
?? ??? ??? ?<artifactId>spring-cloud-starter-openfeign</artifactId>
?? ??? ?</dependency>

最后分析了一下可能是因為feign的版本更新太快導致的吧。

Springcloud feign 異常報錯及解決

報錯異常如下

There was an unexpected error (type=Internal Server Error, status=500).
Type definition error: [simple type, class demo.domain.ApiResult]; nested exception is com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `demo.domain.ApiResult` (no Creators, like default construct, exist): cannot deserialize from Object value (no delegate- or property-based Creator) at [Source: (PushbackInputStream); line: 1, column: 2]

Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is feign.FeignException$InternalServerError: status 500 reading FeignService#test()] with root cause

feign.FeignException$InternalServerError: status 500 reading FeignService#test()
   at feign.FeignException.errorStatus(FeignException.java:114) ~[feign-core-10.2.3.jar:na]
   at feign.FeignException.errorStatus(FeignException.java:86) ~[feign-core-10.2.3.jar:na]
   at feign.codec.ErrorDecoder$Default.decode(ErrorDecoder.java:93) ~[feign-core-10.2.3.jar:na]
   at feign.SynchronousMethodHandler.executeAndDecode(SynchronousMethodHandler.java:149) ~[feign-core-10.2.3.jar:na]
   at feign.SynchronousMethodHandler.invoke(SynchronousMethodHandler.java:78) ~[feign-core-10.2.3.jar:na]
   at feign.ReflectiveFeign$FeignInvocationHandler.invoke(ReflectiveFeign.java:103) ~[feign-core-10.2.3.jar:na]
   at com.sun.proxy.$Proxy77.test(Unknown Source) ~[na:na]
   at demo.controller.ConsumerController.test(ConsumerController.java:25) ~[classes/:na]
   at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_221]
   at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_221]
   at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_221]
   at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_221]
   at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190) ~[spring-web-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138) ~[spring-web-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104) ~[spring-webmvc-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:892) ~[spring-webmvc-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:797) ~[spring-webmvc-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1039) ~[spring-webmvc-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942) ~[spring-webmvc-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005) ~[spring-webmvc-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:897) ~[spring-webmvc-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at javax.servlet.http.HttpServlet.service(HttpServlet.java:634) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882) ~[spring-webmvc-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.22.jar:9.0.22]
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:118) ~[spring-web-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:92) ~[spring-web-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:118) ~[spring-web-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93) ~[spring-web-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:118) ~[spring-web-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200) ~[spring-web-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:118) ~[spring-web-5.1.9.RELEASE.jar:5.1.9.RELEASE]
   at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202) ~[tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490) [tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) [tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) [tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) [tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408) [tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:853) [tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1587) [tomcat-embed-core-9.0.22.jar:9.0.22]
   at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.22.jar:9.0.22]
   at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_221]
   at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_221]
   at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.22.jar:9.0.22]
   at java.lang.Thread.run(Thread.java:748) [na:1.8.0_221]