报错原因: Exception in thread "main" com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server. 看重点:The last packet sent successfully to the se...
CJCommunicationsException: Communications link failure The last packet successfully received from the server was 319 milliseconds ago. The last packet sent successfully to the server was 319 milliseconds ago. 1 2 问题二 Caused by: com.mysql.cj.exceptions.InvalidConnectionAttributeException: The server ...