SpringCloud 程序启动报错 Correct the classpath of your application so that it contains compatible versions

一、报错信息

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APPLICATION FAILED TO START
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Description:

An attempt was made to call a method that does not exist. The attempt was made from the following location:

    org.apache.catalina.authenticator.AuthenticatorBase.startInternal(AuthenticatorBase.java:1318)

The following method did not exist:

    javax.servlet.ServletContext.getVirtualServerName()Ljava/lang/String;

The calling method's class, org.apache.catalina.authenticator.AuthenticatorBase, was loaded from the following location:

    jar:file:/C:/Users/wang_xinxin/.m2/repository/org/apache/tomcat/embed/tomcat-embed-core/9.0.58/tomcat-embed-core-9.0.58.jar!/org/apache/catalina/authenticator/AuthenticatorBase.class

The called method's class, javax.servlet.ServletContext, is available from the following locations:

    jar:file:/C:/Users/wang_xinxin/.m2/repository/javax/servlet/servlet-api/2.5/servlet-api-2.5.jar!/javax/servlet/ServletContext.class
    jar:file:/C:/Users/wang_xinxin/.m2/repository/org/apache/tomcat/embed/tomcat-embed-core/9.0.58/tomcat-embed-core-9.0.58.jar!/javax/servlet/ServletContext.class

The called method's class hierarchy was loaded from the following locations:

    javax.servlet.ServletContext: file:/C:/Users/wang_xinxin/.m2/repository/javax/servlet/servlet-api/2.5/servlet-api-2.5.jar


Action:

Correct the classpath of your application so that it contains compatible versions of the classes org.apache.catalina.authenticator.AuthenticatorBase and javax.servlet.ServletContext

二、报错分析

大概讲的是有两个/javax/servlet/ServletContext.class，导致冲突了。绿色框出来的是哪两个jar包，servlet-api-2.5.jar和tomcat-embed-core-9.0.58.jar。

三、问题解决

1.使用 maven helper 插件（没有的可以idea安装插件），查看 servlet-api 这个jar包是从哪个依赖引进来的，发现是 spring-cloud-starter-netflix-eureka-client 这个依赖引入的。

查看 spring-cloud-starter-netflix-eureka-client 依赖信息：

    org.springframework.cloud
    spring-cloud-starter-netflix-eureka-client
    3.1.1

猜测出错原因：按理说依赖的父模块有spring-cloud-dependencies依赖，子模块引入相关依赖时不应该再指定版本，但是去掉3.1.1后依赖报错。

2. 因为是项目子模块报错，查看父模块的pom.xml
   发现 spring-cloud-dependencies 缺少 pomimport，同时去掉spring-cloud-starter-netflix-eureka-client的版本号，刷新maven，程序不再报错。