Error querying database. Cause: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communicat

Solution: when connecting to the database, change usessl = true to usessl = false. Of course, if usessl = true is not written, it is true by default.

Note: however, I don’t know why I did it. What’s more, the tutorial I read only uses true, and why I report an error. If a boss sees it, he hopes to answer it.

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