即使有 jar 文件也无法将 Java 连接到 MySQL 数据库

Cannot connect Java to MySQL database even after having jar file

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class DbManager {
    public static Connection conn = null; // mysql
    public static void setMysqlDbConnection() throws SQLException, ClassNotFoundException {
        try {
            Class.forName("com.mysql.cj.jdbc.Driver");
            System.out.println("jdbc:mysql://localhost:3306/testdatabase");
            System.out.println("test1");

            conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/testdatabase", "root", "Password");
            System.out.println("test2");
            if (!conn.isClosed())
                System.out.println("Successfully connected to MySQL server");

            } catch (Exception e) {
            System.err.println("Cannot connect to database server");
        }
     }
}

输出为:

jdbc:mysql://localhost:3306/testdatabase
test1
Cannot connect to database server

连接未按预期工作。我已经确认安装的 jar 和连接正在使用终端上的用户名和密码。有谁知道我做错了什么?

在代码中明确提到 serverTimezone 以解决问题。

conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/testdatabase?serverTimezone=UTC", "root", "MyPassword");