写完testController后，mvn clean install内的test报错，内容是找不到 com.mysql.cj.jdbc.Driver
但我的版本及配置多次检查后，没有写过任何com.mysql.cj.jdbc.Driver的信息，这是为何呢。。。
您好，我这边试了很久，一直没有能够复现：
依赖：
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
<version>5.1.47</version>
</dependency>
配置：
spring:
datasource:
url: jdbc:mysql://localhost:3306/user_center?useUnicode=true&characterEncoding=utf8&useSSL=false
username: root
password: root123
driver-class-name: com.mysql.jdbc.Driver
能否帮忙把代码托管到GitHub或者Gitee，我来看看哈。
另外，不建议用Spring Boot 2.2版本进行测试。原因有2：
-
2.2.0版本和课上的2.1.5版本有一定差异，容易采坑。不说别的，数据源的配置就不一样哈
-
Spring Cloud Alibaba和Spring Boot有一定的版本映射关系，在4-2节有详解。目前即使最新的Spring Cloud Alibaba 2.1.0，也只支持Spring Boot 2.1.x
建议严格按照课上选择的版本玩哦，在最近（双十一之前），课程就会更新到最新的版本，并且未来也会持续更新。帮助大家避免采坑的哈。
我下载了hikari的sourceCode，从配置到报错逐层debug，貌似某一层级是根据com.mysql.cj.jdbc.Driver 这个格式去取配置的，配置的com.mysql.jdbc.Driver没有生效。我本地以及平时用mysql5.7比较多，故而为了后面考虑想使用5.7，查看了connector的best practice，貌似8.x是为了兼容mysql的8.x，推荐5.7mysql使用的依旧是5.1.x的connector
2019-10-29
共2条回复
[ERROR] Tests run: 1, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 1.861 s <<< FAILURE! - in com.yaopig.usercenter.UserCenterApplicationTests
[ERROR] contextLoads Time elapsed: 0.001 s <<< ERROR!
java.lang.IllegalStateException: Failed to load ApplicationContext
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'testController': Unsatisfied dependency expressed through field 'userMapper'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userMapper' defined in file [/private/var/www/http/user-center/target/classes/com/yaopig/usercenter/dao/user/UserMapper.class]: Unsatisfied dependency expressed through bean property 'sqlSessionFactory'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [tk/mybatis/mapper/autoconfigure/MapperAutoConfiguration.class]: Unsatisfied dependency expressed through method 'sqlSessionFactory' 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$Hikari.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.zaxxer.hikari.HikariDataSource]: Factory method 'dataSource' threw exception; nested exception is org.springframework.boot.context.properties.bind.BindException: Failed to bind properties under '' to com.zaxxer.hikari.HikariDataSource
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userMapper' defined in file [/private/var/www/http/user-center/target/classes/com/yaopig/usercenter/dao/user/UserMapper.class]: Unsatisfied dependency expressed through bean property 'sqlSessionFactory'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [tk/mybatis/mapper/autoconfigure/MapperAutoConfiguration.class]: Unsatisfied dependency expressed through method 'sqlSessionFactory' parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$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 org.springframework.boot.context.properties.bind.BindException: Failed to bind properties under '' to com.zaxxer.hikari.HikariDataSource
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [tk/mybatis/mapper/autoconfigure/MapperAutoConfiguration.class]: Unsatisfied dependency expressed through method 'sqlSessionFactory' 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$Hikari.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.zaxxer.hikari.HikariDataSource]: Factory method 'dataSource' threw exception; nested exception is org.springframework.boot.context.properties.bind.BindException: Failed to bind properties under '' to com.zaxxer.hikari.HikariDataSource
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'dataSource' defined in class path resource [org/springframework/boot/autoconfigure/jdbc/DataSourceConfiguration$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 org.springframework.boot.context.properties.bind.BindException: Failed to bind properties under '' to com.zaxxer.hikari.HikariDataSource
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.zaxxer.hikari.HikariDataSource]: Factory method 'dataSource' threw exception; nested exception is org.springframework.boot.context.properties.bind.BindException: Failed to bind properties under '' to com.zaxxer.hikari.HikariDataSource
Caused by: org.springframework.boot.context.properties.bind.BindException: Failed to bind properties under '' to com.zaxxer.hikari.HikariDataSource
Caused by: java.lang.IllegalStateException: Unable to set value for property driver-class-name
Caused by: java.lang.reflect.InvocationTargetException
Caused by: java.lang.RuntimeException: Failed to load driver class com.mysql.cj.jdbc.Driver in either of HikariConfig class loader or Thread context classloader
spring:
datasource:
url: jdbc:mysql://localhost:3306/user_center?useUnicode=true&characterEncoding=utf8&useSSL=false
username: 123
password: 123
driver-class-name: com.mysql.jdbc.Driver
# hikari:
# username: 123
# password: 123
# # >= 6.x com.mysql.cj.jdbc.Driver
# # <= 5.x com.mysql.jdbc.Driver
# driver-class-name: com.mysql.jdbc.Driver
替换调hikari后可以通过了。。难道是版本问题，5xx没有cj的不可以用hikari？
spring:
datasource:
url: jdbc:mysql://localhost:3306/user_center?useUnicode=true&characterEncoding=utf8&useSSL=false
hikari:
username: 123
password: 123
# >= 6.x com.mysql.cj.jdbc.Driver
# <= 5.x com.mysql.jdbc.Driver
driver-class-name: com.mysql.jdbc.Driver
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.2.0.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.yaopig</groupId>
<artifactId>user-center</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>user-center</name>
<description>aaa user-center</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>tk.mybatis</groupId>
<artifactId>mapper-spring-boot-starter</artifactId>
<version>2.1.5</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.48</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-maven-plugin</artifactId>
<version>1.3.6</version>
<configuration>
<configurationFile>
${basedir}/src/main/resources/generator/generatorConfig.xml
</configurationFile>
<overwrite>true</overwrite>
<verbose>true</verbose>
</configuration>
<dependencies>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.48</version>
</dependency>
<dependency>
<groupId>tk.mybatis</groupId>
<artifactId>mapper</artifactId>
<version>4.1.5</version>
</dependency>
</dependencies>
</plugin>
</plugins>
</build>
</project>
