jdbc怎么连接mysql数据库代码

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

public class JDBCTutorial {
    public static void main(String[] args) {
        Connection connection = null;
        Statement statement = null;
        ResultSet resultSet = null;

        try {
            // 注册JDBC驱动程序
            Class.forName("com.mysql.cj.jdbc.Driver");

            // 打开连接
            String url = "jdbc:mysql://localhost:3306/mydatabase";
            String user = "username";
            String password = "password";
            connection = DriverManager.getConnection(url, user, password);

            // 执行查询
            statement = connection.createStatement();
            String sql = "SELECT id, name, age FROM users";
            resultSet = statement.executeQuery(sql);

            // 处理结果集
            while (resultSet.next()) {
                int id = resultSet.getInt("id");
                String name = resultSet.getString("name");
                int age = resultSet.getInt("age");
                System.out.println("ID: " + id + ", Name: " + name + ", Age: " + age);
            }
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            // 关闭资源
            try {
                if (resultSet != null) resultSet.close();
                if (statement != null) statement.close();
                if (connection != null) connection.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}