JAVA GUI SimpleShape.java

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

public class SimpleShape extends JPanel
{
public void paintComponent(Graphics g){
//請上層容器重畫，已清除原有的內容
super.paintComponent(g);
//取得面板的寬與高
double Width = getSize().width - 10;
double Height = getSize().height / 4 - 10;
Graphics2D g2 = (Graphics2D) g;
g2.draw(new Line2D.Double(5,5,5+Width,5+Height)); //畫線
g2.draw(new Rectangle2D.Double(5,10+Height,Width,Height)); //畫矩形
g2.draw(new RoundRectangle2D.Double(5,15+2*Height,Width,Height,20,30)); //化園角矩型
g2.draw(new Ellipse2D.Double(5,20+ 3*Height,Width,Height)); //畫橢圓


}
public static void main(String[] args){
JFrame f = new JFrame("幾何圖形");
f.getContentPane().add(new SimpleShape());
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(640,480);
f.setVisible(true);
}
}