spring boot 异常： Cannot load driver class: com.mysql.jdbc.Driver

在整合mybatis时出现异常

Caused by: java.lang.IllegalStateException: Cannot load driver class: com.mysql.jdbc.Driver
	at org.springframework.util.Assert.state(Assert.java:70) ~[spring-core-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	at org.springframework.boot.autoconfigure.jdbc.DataSourceProperties.determineDriverClassName(DataSourceProperties.java:232) ~[spring-boot-autoconfigure-1.5.9.RELEASE.jar:1.5.9.RELEASE]
	at org.springframework.boot.autoconfigure.jdbc.DataSourceProperties.initializeDataSourceBuilder(DataSourceProperties.java:184) ~[spring-boot-autoconfigure-1.5.9.RELEASE.jar:1.5.9.RELEASE]
	at org.springframework.boot.autoconfigure.jdbc.DataSourceConfiguration.createDataSource(DataSourceConfiguration.java:42) ~[spring-boot-autoconfigure-1.5.9.RELEASE.jar:1.5.9.RELEASE]
	at org.springframework.boot.autoconfigure.jdbc.DataSourceConfiguration$Tomcat.dataSource(DataSourceConfiguration.java:56) ~[spring-boot-autoconfigure-1.5.9.RELEASE.jar:1.5.9.RELEASE]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_192]
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_192]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_192]
	at java.lang.reflect.Method.invoke(Unknown Source) ~[na:1.8.0_192]
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:162) ~[spring-beans-4.3.13.RELEASE.jar:4.3.13.RELEASE]
	... 62 common frames omitted

出现原因：maven仓库缺少依赖

解决办法：在pom.xml中添加依赖

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>5.1.38</version>
</dependency>

同时注意在application.properties 文件中的配置： spring.datasource.driver-class-name=com.mysql.jdbc.Driver，是否拼写正确，注意最后的空格