1、遇到如下问题

Sun Jan 09 14:19:41 CST 2022 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. 
For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. 
You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification.

2、解决方法

在url后面加上如图的内容

如url后又多个参数，这样加入即可

spring.datasource.url=jdbc:mysql://localhost:3306/springboot?characterEncoding=utf-8&useSSL=false