SpringCloud：Feign模塊引用版本問題

1.問題報錯

org.springframework.beans.factory.BeanDefinitionStoreException: Failed to process import candidates for configuration class [com.fdzang.microservice.gateway.GatewayApplication]; nested exception is java.io.FileNotFoundException: class path resource [org/springframework/boot/autoconfigure/web/ServerPropertiesAutoConfiguration.class] cannot be opened because it does not exist
   
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-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.core.type.classreading.SimpleMetadataReader.<init>(SimpleMetadataReader.java:51) ~[spring-core-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:103) ~[spring-core-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.boot.type.classreading.ConcurrentReferenceCachingMetadataReaderFactory.createMetadataReader(ConcurrentReferenceCachingMetadataReaderFactory.java:86) ~[spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
    at org.springframework.boot.type.classreading.ConcurrentReferenceCachingMetadataReaderFactory.getMetadataReader(ConcurrentReferenceCachingMetadataReaderFactory.java:73) ~[spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
    at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:81) ~[spring-core-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.context.annotation.ConfigurationClassParser.asSourceClass(ConfigurationClassParser.java:682) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.context.annotation.ConfigurationClassParser$SourceClass.getRelated(ConfigurationClassParser.java:1074) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.context.annotation.ConfigurationClassParser$SourceClass.getAnnotationAttributes(ConfigurationClassParser.java:1055) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.context.annotation.ConfigurationClassParser.collectImports(ConfigurationClassParser.java:538) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.context.annotation.ConfigurationClassParser.getImports(ConfigurationClassParser.java:511) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.context.annotation.ConfigurationClassParser.doProcessConfigurationClass(ConfigurationClassParser.java:302) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.context.annotation.ConfigurationClassParser.processConfigurationClass(ConfigurationClassParser.java:242) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.context.annotation.ConfigurationClassParser.processImports(ConfigurationClassParser.java:586) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    ... 19 common frames omitted

從報錯來看是文件找不到異常，推測是引用有問題，應該有依賴沒有加進來

pom文件以下：

<dependency>
　　<groupId>org.springframework.cloud</groupId>
　　<artifactId>spring-cloud-starter-feign</artifactId>
　　<version>1.4.7.RELEASE</version>
</dependency>

因而加入Hystrix相關依賴，依舊報錯

2.解決辦法

百度：https://blog.csdn.net/poem_2010/article/details/88847285

查看以後有點思路，就是Feign版本的問題，忽然想起來以前寫的一篇博客：https://www.cnblogs.com/fdzang/p/10304143.html

在新版本springcloud中新增了一個組件：spring-cloud-openfeign

Spring Cloud對Feign的支持由org.springframework.cloud:spring-cloud-netflix-core移到org.springframework.cloud:spring-cloud-openfeign-core

因而去maven倉庫搜索：spring-cloud-openfeign，沒找到，找到了：spring-cloud-starter-openfeign

<!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-openfeign -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-openfeign</artifactId>
    <version>2.1.3.RELEASE</version>
</dependency>

因而替換pom中feign相關依賴，並更新以前的註解引用，重啓，完成。