No suitable driver found for jdbc:mysql://localhost/centralsystem

缺少下边中的某一个

mysql:mysql-connector-java:5.1.40

mysql:mysql-connector-java:8.0.20

其次，还需要配置好你的url

String url = "jdbc:mysql://localhost/" + databaseName+"?useSSL=false&serverTimezone=GMT&characterEncoding=UTF-8";