用JFrame创建两个窗口

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

public class windows {
     public static void main(String[] args) {
		JFrame window1=new JFrame("第一个窗口");
		JFrame window2=new JFrame("第二个窗口");
		Container con=window1.getContentPane();
		con.setBackground(Color.yellow);
		window1.setBounds(60,100,188,108);
		window2.setBounds(260,100,188,108);
		window1.setVisible(true);
		window1.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
		window2.setVisible(true);
		window2.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);	
     }
}