Error message

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.

Solution:

#Modify database connection Add useSSL=true
jdbc:mysql://localhost:3306/aa?useUnicode=true&characterEncoding=utf-8&useSSL=true

Where usessl = true means that when the JDBC version is inconsistent with the MySQL version, when using JDBC to connect to your database, your JDBC version is incompatible with the MySQL version. The MySQL version is higher. Add “usessl =” true “after the connection statement to connect to the database.