java怎么换mysql数据库

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

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

        try {
            // 1. 注册JDBC驱动
            Class.forName("com.mysql.jdbc.Driver");

            // 2. 建立数据库连接
            connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/database_name", "username", "password");

            // 3. 创建Statement对象，用于执行SQL语句
            statement = connection.createStatement();

            // 4. 执行SQL查询
            resultSet = statement.executeQuery("SELECT * FROM table_name");

            // 5. 处理结果集
            while (resultSet.next()) {
                // 获取结果集中的数据
                String column1 = resultSet.getString("column1");
                int column2 = resultSet.getInt("column2");
                // 其他操作...
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } finally {
            try {
                // 6. 关闭连接和释放资源
                if (resultSet != null) {
                    resultSet.close();
                }
                if (statement != null) {
                    statement.close();
                }
                if (connection != null) {
                    connection.close();
                }
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}