JDBC连接Mysql时警告：Establishing SSL connection without server’s identity verification is not recommended

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.

Reason：

      在MySQL高版本中需要指明是否进行SSL，进行数据加密

       不建议在没有服务器身份验证的情况下建立SSL连接。根据MySQL 5.5.45+、5.6.26+和5.7.6+的要求，如果没有设置明确的选项，SSL连接必须默认建立。为了符合不使用SSL的现有应用程序，verifyServerCertificate属性被设置为 "false"。你需要通过设置useSSL=false明确地禁用SSL，或者设置useSSL=true并为服务器证书验证提供truststore。

Solution：

       连接数据URL时添加 useSSL=false，即可：

static final String DB_URL="jdbc:mysql://localhost:3306/book_test?serverTimezone=CTT&useSSL=false";