控制台错误日志：
Description:Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured.Reason: Failed to determine a suitable driver classAction:Consider the following:If you want an embedded database (H2, HSQL or Derby), please put it on the classpath.If you have database settings to be loaded from a particular profile you may need to activate it (no profiles are currently active).1.使用了数据库，但没有在application.properties里配置mysql的配置
重新启动即可
2.没有用到数据库但是导入了相关依赖，只需在pom.xml里将相关的依赖注释掉即可
重新启动即可
