该问题可能是由于流布局在边界布局中的位置造成的。可以尝试将流布局放置在边界布局的中央部分，或使用其他布局替代流布局。以下是一个示例代码：

import java.awt.BorderLayout; import java.awt.FlowLayout; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JPanel;

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

BorderLayout borderLayout = new BorderLayout();
JPanel mainPanel = new JPanel(borderLayout);

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

JPanel flowPanel = new JPanel(new FlowLayout());
flowPanel.add(new JButton("Flow Button 1"));
flowPanel.add(new JButton("Flow Button 2"));
flowPanel.add(new JButton("Flow Button 3"));

mainPanel.add(button1, BorderLayout.NORTH);
mainPanel.add(button2, BorderLayout.SOUTH);
mainPanel.add(flowPanel, BorderLayout.CENTER);

frame.getContentPane().add(mainPanel);
frame.pack();
frame.setVisible(true);

} }