3月16日，BoderLayoutDemo，每日20行。

import java.awt.*;
public class BoderLayoutDemo {

    public static void main(String[] args) {
        Frame f = new Frame("BorderLayout Sample");
        f.setLayout(new BorderLayout());
        Button north = new Button("North");
        Button south = new Button("South");
        Button west = new Button("West");
        Button east = new Button("East");
        Button center = new Button("Center");
        f.add(north,BorderLayout.NORTH);
        f.add(south,BorderLayout.SOUTH);
        f.add(west,BorderLayout.WEST);
        f.add(east,BorderLayout.EAST);
        f.add(center,BorderLayout.CENTER);
        f.setSize(400,400);
        f.setVisible(true);
    }

}