程序代码：

package demo;

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();
        JPanel panel = new JPanel();
        JButton okBtn = new JButton("确定");                
        frame.setSize(513,341);        
        frame.setContentPane(panel);
        panel.setLayout(null);    
        panel.add(okBtn);        
        okBtn.setBounds(351, 281, 69, 20);            
        frame.setVisible(true);        
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
}

程序代码：

package demo;

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

public class Test {
    public static void main(String[] args) {
        final JFrame frame = new JFrame();
        JPanel panel = new JPanel();
        final JButton okBtn = new JButton("确定");
        frame.setSize(513, 341);
        frame.setContentPane(panel);
        panel.setLayout(null);
        panel.add(okBtn);
        okBtn.setBounds(351, 281, 69, 20);
        frame.setVisible(true);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        frame.addComponentListener(new ComponentAdapter() {
            @Override
            public void componentResized(ComponentEvent e) {
                okBtn.setBounds(frame.getWidth() - 513 + 351, frame.getHeight() - 341 + 281, 69, 20);
            }
        });
    }
}