如何在java swing中创建3个按钮来占据它们所添加到的面板的1/3？

import javax.swing.*;
import java.awt.*;

public class ButtonPanel extends JPanel {
    public ButtonPanel() {
        setLayout(new GridLayout(1, 3)); // 使用GridLayout布局管理器，将面板分为1行3列

        JButton button1 = new JButton("Button 1");
        JButton button2 = new JButton("Button 2");
        JButton button3 = new JButton("Button 3");

        add(button1);
        add(button2);
        add(button3);
    }

    public static void main(String[] args) {
        JFrame frame = new JFrame("Button Panel");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        ButtonPanel buttonPanel = new ButtonPanel();
        frame.getContentPane().add(buttonPanel);

        frame.pack();
        frame.setVisible(true);
    }
}