[SpringBoot Error] Cannot load driver class: com.mysql.cj.jdbc.Driver (해결)

 

SpringBoot 환경설정 중 책과 오픈소스들로 스터디 하는 중 해당 에러가 발생했다.

처음 환경 잡을때는 발생하지 않다가 Controller 작업하다가 DB 접근 해야되서 발생한건지? 모르겠지만 application 설정 관련 에러인것 같다.

 

정확하게 전체 에러는 다음과 같았다.

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'inMemoryDatabaseShutdownExecutor' defined in class path resource [org/springframework/boot/devtools/autoconfigure/DevToolsDataSourceAutoConfiguration.class]: Unsatisfied dependency expressed through method 'inMemoryDatabaseShutdownExecutor' parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Hikari.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.zaxxer.hikari.HikariDataSource]: Factory method 'dataSource' threw exception; nested exception is java.lang.IllegalStateException: Cannot load driver class: com.mysql.cj.jdbc.Driver
	at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:732) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:474) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1247) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1096) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:535) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:495) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$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.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:304) ~[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.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1089) ~[spring-context-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:859) ~[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.tide.ami.TideAmiApplication.main(TideAmiApplication.java:10) [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.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) [spring-boot-devtools-2.0.4.RELEASE.jar:2.0.4.RELEASE]
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$Hikari.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.zaxxer.hikari.HikariDataSource]: Factory method 'dataSource' threw exception; nested exception is java.lang.IllegalStateException: Cannot load driver class: com.mysql.cj.jdbc.Driver
	at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:590) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1247) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1096) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:535) ~[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.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:251) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1135) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1062) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:818) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:724) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	... 26 common frames omitted
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.zaxxer.hikari.HikariDataSource]: Factory method 'dataSource' threw exception; nested exception is java.lang.IllegalStateException: Cannot load driver class: com.mysql.cj.jdbc.Driver
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:582) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	... 39 common frames omitted
Caused by: java.lang.IllegalStateException: Cannot load driver class: com.mysql.cj.jdbc.Driver
	at org.springframework.util.Assert.state(Assert.java:94) ~[spring-core-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	at org.springframework.boot.autoconfigure.jdbc.DataSourceProperties.determineDriverClassName(DataSourceProperties.java:224) ~[spring-boot-autoconfigure-2.0.4.RELEASE.jar:2.0.4.RELEASE]
	at org.springframework.boot.autoconfigure.jdbc.DataSourceProperties.initializeDataSourceBuilder(DataSourceProperties.java:176) ~[spring-boot-autoconfigure-2.0.4.RELEASE.jar:2.0.4.RELEASE]
	at org.springframework.boot.autoconfigure.jdbc.DataSourceConfiguration.createDataSource(DataSourceConfiguration.java:43) ~[spring-boot-autoconfigure-2.0.4.RELEASE.jar:2.0.4.RELEASE]
	at org.springframework.boot.autoconfigure.jdbc.DataSourceConfiguration$Hikari.dataSource(DataSourceConfiguration.java:83) ~[spring-boot-autoconfigure-2.0.4.RELEASE.jar:2.0.4.RELEASE]
	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.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
	... 40 common frames omitted

 

맨 위 에러부터 구글링 했는데 해당 에러 해결에는 도움되진 않았고, 제일 아래 에러가 원인이였는데 

com.mysql.cj.jdbc.driver 클래스를 못찾는게 원인이였다.

 

 

해결방법

SpringBoot 프로젝트경로 기준 src/main/resources의 application.properties 파일 내용을 수정해준다.

spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

위와 같이 설정된 부분을 

 

spring.datasource.driver-class-name=com.mysql.jdbc.Driver

com.mysql. 뒤 cj를 지워준다.

원인은 SpringBoot 프로젝트에서는  mysql 버전에 따라 드라이버를 다르게 명시해주어야 하나보다.

cj를 지워주고 빌드하니 에러없이 아주 잘되는것을 확인했다.