java,枯燥中遇见美丽JFrame，窗体（网格布局）

package com.company;

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

public class Main extends JFrame {
    public Main(){
        setBounds(100,100,300,300);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        Container c=getContentPane();
       c.setLayout(new GridLayout(7,3,5,5));//设置为网格布局，7行3列，水平间距为5像素，垂直间距为5
        for (int i=1;i<=20;i++){
            c.add(new JButton("按钮"+i));
        }
        setVisible(true);
    }

    public static void main(String[] args) {
        new Main();
    // write your code here
    }
}

当设定的水平垂直，间距不再适应时，网格布局会自动调整