概述
Feign能干什么
feign旨在使編寫java http客戶端變的更容易
前面在使用Ribbon+RestTemplate時(shí)，利用RestTemplate對(duì)http請(qǐng)求的封裝處理所刀，形成了一套膜版畫的調(diào)用方法。但是在實(shí)際開發(fā)中山涡，由于對(duì)服務(wù)依賴的調(diào)用可能不止一處幻碱，往往一個(gè)接口會(huì)被多處調(diào)用狂秦，所以通常都會(huì)針對(duì)每個(gè)微服務(wù)自行封裝一些客戶端類來包裝這些依賴服務(wù)的調(diào)用。所以治专，F(xiàn)eign在此基礎(chǔ)上做了進(jìn)一步封裝卖陵，由他來幫助我們定義和實(shí)現(xiàn)依賴服務(wù)接口的定義。在Feign的實(shí)現(xiàn)下张峰，我們只需要?jiǎng)?chuàng)建一個(gè)接口并使用注解的方式來配置他(以前是在DAO接口上面標(biāo)注Mapper注解泪蔫，現(xiàn)在是在一個(gè)微服務(wù)接口上面標(biāo)注一個(gè)Feign注解即可),即可完成對(duì)服務(wù)提供方的接口綁定，簡(jiǎn)化了使用Spring cloud Ribbon時(shí)喘批，自動(dòng)封裝服務(wù)調(diào)用客戶端的開發(fā)量撩荣。
Feign集成了Ribbon
利用Ribbon維護(hù)了SPRINGBOOT-MYBATIS-PROVIDER-001的服務(wù)列表信息，并且通過輪詢實(shí)現(xiàn)了客戶端的負(fù)載均衡饶深。而與Ribbon不同額是餐曹，通過feign只需要定義服務(wù)綁定接口且以聲明式的方法，優(yōu)雅而簡(jiǎn)單的實(shí)現(xiàn)了服務(wù)調(diào)用
公共api中包括要提供出去的服務(wù)接口以及實(shí)體類敌厘，在此先上一些踩過的坑
當(dāng)api項(xiàng)目的pom.xml中依賴的是下面代碼中的包時(shí)
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-feign</artifactId>
<version>1.4.7.RELEASE</version>
</dependency>
服務(wù)提供者依賴了api包台猴，啟動(dòng)類啟動(dòng)時(shí)報(bào)如下錯(cuò)誤
org.springframework.beans.factory.BeanDefinitionStoreException: Failed to process import candidates for configuration class [com.hc.config.SwaggerConfig]; nested exception is java.io.FileNotFoundException: class path resource [org/springframework/boot/autoconfigure/web/ServerPropertiesAutoConfiguration.class] cannot be opened because it does not exist
at org.springframework.context.annotation.ConfigurationClassParser.processImports(ConfigurationClassParser.java:596) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassParser.access$900(ConfigurationClassParser.java:108) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassParser$DeferredImportSelectorGroupingHandler.lambda$processGroupImports$1(ConfigurationClassParser.java:805) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at java.util.ArrayList.forEach(ArrayList.java:1257) ~[na:1.8.0_191]
at org.springframework.context.annotation.ConfigurationClassParser$DeferredImportSelectorGroupingHandler.processGroupImports(ConfigurationClassParser.java:801) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassParser$DeferredImportSelectorHandler.process(ConfigurationClassParser.java:771) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:185) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:315) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:232) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:275) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:95) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:705) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:531) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) ~[spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:742) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:389) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:311) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1213) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1202) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at com.hc.ApplicationProvider001.main(ApplicationProvider001.java:90) [classes/:na]
Caused by: java.io.FileNotFoundException: class path resource [org/springframework/boot/autoconfigure/web/ServerPropertiesAutoConfiguration.class] cannot be opened because it does not exist
at org.springframework.core.io.ClassPathResource.getInputStream(ClassPathResource.java:180) ~[spring-core-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.core.type.classreading.SimpleMetadataReader.<init>(SimpleMetadataReader.java:51) ~[spring-core-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:103) ~[spring-core-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.boot.type.classreading.ConcurrentReferenceCachingMetadataReaderFactory.createMetadataReader(ConcurrentReferenceCachingMetadataReaderFactory.java:86) ~[spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at org.springframework.boot.type.classreading.ConcurrentReferenceCachingMetadataReaderFactory.getMetadataReader(ConcurrentReferenceCachingMetadataReaderFactory.java:73) ~[spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:81) ~[spring-core-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassParser.asSourceClass(ConfigurationClassParser.java:682) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassParser$SourceClass.getRelated(ConfigurationClassParser.java:1074) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassParser$SourceClass.getAnnotationAttributes(ConfigurationClassParser.java:1055) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassParser.collectImports(ConfigurationClassParser.java:538) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassParser.getImports(ConfigurationClassParser.java:511) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassParser.doProcessConfigurationClass(ConfigurationClassParser.java:302) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassParser.processConfigurationClass(ConfigurationClassParser.java:242) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.annotation.ConfigurationClassParser.processImports(ConfigurationClassParser.java:586) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
... 19 common frames omitted
最終經(jīng)查證，發(fā)現(xiàn)feign的包應(yīng)該依賴如下：
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
<version>2.1.2.RELEASE</version>
</dependency>
-----------end----------最終解決了提供者啟動(dòng)報(bào)錯(cuò)問題俱两。
=================================================================
springboot-mybatis-consumer-feign中的代碼如下：
啟動(dòng)類
package com.hc;
import org.apache.log4j.Logger;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;
@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})
@EnableDiscoveryClient
@EnableFeignClients(basePackages = {"com.hc"}) //使用feign代替ribbon
public class AppUserConsumerFeign001 {
private static Logger logger = Logger.getLogger(AppUserConsumerFeign001.class);
/**
* Start
*/
public static void main(String[] args) {
SpringApplication.run(AppUserConsumerFeign001.class, args);
// logger.info("SpringBoot Start Success");
}
}
controller類
package com.hc.controller;
import com.hc.model.User;
import com.hc.service.UserClientService;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.client.RestTemplate;
import java.util.List;
/**
*/
@Controller
@RequestMapping("/consumerFeign001")
public class UserClientController {
private Logger logger = Logger.getLogger(UserClientController.class);
@Autowired
UserClientService userClientService;
@RequestMapping("/getUsers")
@ResponseBody
public List<User> getUsers() {
return userClientService.getUsers();
}
}
依賴的公共接口提供模塊api(spring-mybatis-api)饱狂，代碼如下：
@FeignClient(value="SPRINGBOOT-MYBATIS-PROVIDER-001")
public interface UserClientService {
@RequestMapping("/getUsers")
List<User> getUsers();
}
服務(wù)提供者(springboot-mybatis-provider)controller中代碼如下：
@RequestMapping("/getUserInfo")
@ResponseBody
public List<User> getUserInfo() {
List<User> userList = userService.getUserInfo();
if(userList!=null){
System.out.println("user.getName():"+userList.get(0).getName());
logger.info("user.getAge():"+userList.get(0).getAge());
}
return userList;
}
方法名不規(guī)范，請(qǐng)忽略宪彩，此方法是查詢所有用戶的
首次訪問結(jié)果如下：
報(bào)錯(cuò)信息
排查原因------------------------start--------------------------------------
發(fā)現(xiàn)api中提供的接口路徑與提供者提供的接口路徑不一致休讳，如下：
#api中service中代碼片段
@FeignClient(value="SPRINGBOOT-MYBATIS-PROVIDER-001")
public interface UserClientService {
@RequestMapping("/getUsers")
List<User> getUsers();
}
#提供者controller中代碼片段
@RequestMapping("/getUserInfo")
@ResponseBody
public List<User> getUserInfo() {
List<User> userList = userService.getUserInfo();
if(userList!=null){
System.out.println("user.getName():"+userList.get(0).getName());
logger.info("user.getAge():"+userList.get(0).getAge());
}
return userList;
}
結(jié)果發(fā)現(xiàn)兩者的路徑不同，然后將api中的路徑與提供者controller中的路徑進(jìn)行統(tǒng)一
#api中service中代碼片段
@FeignClient(value="SPRINGBOOT-MYBATIS-PROVIDER-001")
public interface UserClientService {
@RequestMapping("/getUserInfo")
List<User> getUsers();
}
#提供者controller中代碼片段
@RequestMapping("/getUserInfo")
@ResponseBody
public List<User> getUserInfo() {
List<User> userList = userService.getUserInfo();
if(userList!=null){
System.out.println("user.getName():"+userList.get(0).getName());
logger.info("user.getAge():"+userList.get(0).getAge());
}
return userList;
}
再次訪問毯焕，結(jié)果如下：
默認(rèn)feign使用的是輪詢算法
排查原因------------------------end--------------------------------------
注意：此處也給大家展示一個(gè)濤哥踩得大坑衍腥，這個(gè)坑是真的坑，而且是稍不注意就會(huì)導(dǎo)致大家話費(fèi)很長(zhǎng)的時(shí)間來找纳猫，并且不一定能找到的坑
api（springb-mybatis-api）中的原代碼，會(huì)導(dǎo)致springboot-mybatis-feign的啟動(dòng)報(bào)錯(cuò)
報(bào)錯(cuò)信息是這樣的
org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userConsumerFeign002Controller': Unsatisfied dependency expressed through field 'userClientService'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.hc.service.UserClientService': FactoryBean threw exception on object creation; nested exception is java.lang.IllegalStateException: PathVariable annotation was empty on param 0.
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:596) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:90) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:374) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1411) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:592) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:845) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:877) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549) ~[spring-context-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) ~[spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:742) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:389) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:311) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1213) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1202) [spring-boot-2.1.6.RELEASE.jar:2.1.6.RELEASE]
at com.hc.ApplicationConsumerfeign002.main(ApplicationConsumerfeign002.java:20) [classes/:na]
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.hc.service.UserClientService': FactoryBean threw exception on object creation; nested exception is java.lang.IllegalStateException: PathVariable annotation was empty on param 0.
at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:178) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.getObjectFromFactoryBean(FactoryBeanRegistrySupport.java:101) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getObjectForBeanInstance(AbstractBeanFactory.java:1674) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.getObjectForBeanInstance(AbstractAutowireCapableBeanFactory.java:1249) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:257) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:277) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.addCandidateEntry(DefaultListableBeanFactory.java:1474) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1431) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1214) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1171) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:593) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
... 19 common frames omitted
Caused by: java.lang.IllegalStateException: PathVariable annotation was empty on param 0.
at feign.Util.checkState(Util.java:130) ~[feign-core-10.2.3.jar:na]
at org.springframework.cloud.openfeign.annotation.PathVariableParameterProcessor.processArgument(PathVariableParameterProcessor.java:52) ~[spring-cloud-openfeign-core-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at org.springframework.cloud.openfeign.support.SpringMvcContract.processAnnotationsOnParameter(SpringMvcContract.java:292) ~[spring-cloud-openfeign-core-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at feign.Contract$BaseContract.parseAndValidateMetadata(Contract.java:110) ~[feign-core-10.2.3.jar:na]
at org.springframework.cloud.openfeign.support.SpringMvcContract.parseAndValidateMetadata(SpringMvcContract.java:188) ~[spring-cloud-openfeign-core-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at feign.Contract$BaseContract.parseAndValidatateMetadata(Contract.java:66) ~[feign-core-10.2.3.jar:na]
at feign.ReflectiveFeign$ParseHandlersByName.apply(ReflectiveFeign.java:154) ~[feign-core-10.2.3.jar:na]
at feign.ReflectiveFeign.newInstance(ReflectiveFeign.java:52) ~[feign-core-10.2.3.jar:na]
at feign.Feign$Builder.target(Feign.java:251) ~[feign-core-10.2.3.jar:na]
at org.springframework.cloud.openfeign.HystrixTargeter.target(HystrixTargeter.java:36) ~[spring-cloud-openfeign-core-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at org.springframework.cloud.openfeign.FeignClientFactoryBean.loadBalance(FeignClientFactoryBean.java:238) ~[spring-cloud-openfeign-core-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at org.springframework.cloud.openfeign.FeignClientFactoryBean.getTarget(FeignClientFactoryBean.java:267) ~[spring-cloud-openfeign-core-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at org.springframework.cloud.openfeign.FeignClientFactoryBean.getObject(FeignClientFactoryBean.java:247) ~[spring-cloud-openfeign-core-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:171) ~[spring-beans-5.1.8.RELEASE.jar:5.1.8.RELEASE]
... 30 common frames omitted
產(chǎn)生這個(gè)錯(cuò)誤的原因如下
@FeignClient(value="SPRINGBOOT-MYBATIS-PROVIDER-001")
UserClientServiceFallbackFactory.class)
public interface UserClientService {
@RequestMapping("/getUserInfo")
List<User> getUsers();
@RequestMapping(value = "/getRealUserInfo/{id}" , method = RequestMethod.GET)
// 原先不規(guī)范寫法會(huì)導(dǎo)致消費(fèi)端啟動(dòng)報(bào)錯(cuò)竹捉，大家一定要注意
User getRealUserInfo(@PathVariable Integer id);
// 規(guī)范的寫法
// User getRealUserInfo(@PathVariable("id") Integer id);
}
