記一次nacos啟動報錯：Could not initialize class org.hibernate.validator.internal.engine.valueextraction.ValueExtractorManager

背景

最近在學習nacos，拿了官方的樣例在本地跑，但是在跑nacos-spring-cloud-example時，一直啟動不起來，報錯信息如下：

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2021-08-06 18:58:34.385 ERROR 7733 --- [           main] o.s.boot.SpringApplication               : Application run failed

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'defaultValidator' defined in class path resource [org/springframework/boot/autoconfigure/validation/ValidationAutoConfiguration.class]: Invocation of init method failed; nested exception is java.lang.NoClassDefFoundError: Could not initialize class org.hibernate.validator.internal.engine.valueextraction.ValueExtractorManager
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1699) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:573) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:495) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:759) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:869) ~[spring-context-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) ~[spring-context-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) ~[spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:762) [spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:398) [spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:330) [spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1258) [spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1246) [spring-boot-2.0.4.RELEASE.jar:2.0.4.RELEASE]
	at com.alibaba.nacos.example.spring.cloud.NacosProviderApplication.main(NacosProviderApplication.java:19) [classes/:na]
Caused by: java.lang.NoClassDefFoundError: Could not initialize class org.hibernate.validator.internal.engine.valueextraction.ValueExtractorManager
	at org.hibernate.validator.internal.engine.ValidatorFactoryImpl.<init>(ValidatorFactoryImpl.java:140) ~[hibernate-validator-6.0.11.Final.jar:6.0.11.Final]
	at org.hibernate.validator.HibernateValidator.buildValidatorFactory(HibernateValidator.java:38) ~[hibernate-validator-6.0.11.Final.jar:6.0.11.Final]
	at org.hibernate.validator.internal.engine.ConfigurationImpl.buildValidatorFactory(ConfigurationImpl.java:364) ~[hibernate-validator-6.0.11.Final.jar:6.0.11.Final]
	at org.springframework.validation.beanvalidation.LocalValidatorFactoryBean.afterPropertiesSet(LocalValidatorFactoryBean.java:309) ~[spring-context-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1758) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1695) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	... 16 common frames omitted

分析

看報錯，是沒有"org.hibernate.validator.internal.engine.valueextraction.ValueExtractorManager"類定義導致的，但是我的maven倉庫里面是有這個jar包的，查看jar內容也是能看到存在該類的，也參考了https://www.iteye.com/blog/blessht-1104450的說法，耗費好長時間沒找出原因。懷疑是jar沖突導致的，但是我看maven引入的包也沒有其他類似的包，最后只嘗試換一個版本試下，結果跑成功了。。。

解決方案

            <dependency>
                <groupId>org.hibernate.validator</groupId>
                <artifactId>hibernate-validator</artifactId>
                <version>6.0.11.Final</version>
            </dependency>

把版本6.0.11.Final換成其他版本就成功了，例如6.0.20.Final

后續

以后如果技術有增進再來研究