如何使用JDBC更新MySQL-PreparedStatement中未知数量的列？

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

String url = "jdbc:mysql://localhost:3306/mydatabase";
String username = "root";
String password = "password";
Connection connection = DriverManager.getConnection(url, username, password);

String sql = "UPDATE table_name SET column1 = ?, column2 = ?, column3 = ? WHERE condition";
PreparedStatement statement = connection.prepareStatement(sql);

statement.setString(1, value1);
statement.setString(2, value2);
statement.setString(3, value3);

int rowsAffected = statement.executeUpdate();

statement.close();
connection.close();