JavaFX无法将数字添加到数据库列

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.stage.Stage;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;

String url = "jdbc:mysql://localhost:3306/database_name";
String username = "your_username";
String password = "your_password";

Connection connection = DriverManager.getConnection(url, username, password);

public class Main extends Application {
    @Override
    public void start(Stage primaryStage) {
        Button addButton = new Button("Add Number");
        addButton.setOnAction(e -> {
            try {
                // 获取用户输入的数字
                int number = 123;

                // 准备插入数据的SQL语句
                String sql = "INSERT INTO table_name (column_name) VALUES (?)";

                // 创建预处理语句对象
                PreparedStatement statement = connection.prepareStatement(sql);

                // 设置参数
                statement.setInt(1, number);

                // 执行插入操作
                statement.executeUpdate();

                // 关闭预处理语句
                statement.close();
            } catch (SQLException ex) {
                ex.printStackTrace();
            }
        });

        Scene scene = new Scene(new StackPane(addButton), 300, 200);
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}