/**
 *　在面板中繪制2D圖形
 */

import javax.swing.JFrame;
import java.awt.Toolkit;
import java.awt.Image;
import java.awt.Dimension;
import java.awt.Container;
import java.awt.Graphics;
import javax.swing.JPanel;
import java.awt.geom.Rectangle2D;
import java.awt.geom.Line2D;
import java.awt.geom.Ellipse2D;
import java.awt.Graphics2D;

public class DrawShapeTest
{
	public static void main(String[] args)
	{
		BlankFrame frame = new BlankFrame();
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.show();
	} 
}

/**
 *　這是定制自己的框架
 */
class BlankFrame extends JFrame
{
	private static final int WIDTH = 400;
	private static final int HEIGHT = 300;
	public BlankFrame()
	{
		Container con = getContentPane();//得到了內容窗格
		
		Toolkit kit = Toolkit.getDefaultToolkit();
		Dimension screenSize = kit.getScreenSize();
		int width = screenSize.width;
		int height = screenSize.height;
		int x = (width - WIDTH)/2;
		int y = (height - HEIGHT)/2;
		setLocation(x, y);//設置坐標起點
		setSize(WIDTH, HEIGHT);//設置框架的大小
		Image image = kit.getImage("duke.gif");// duke.gif為圖像文件名
		setIconImage(image);//設置框架圖標
		setTitle("這是我美化的框架");
		setResizable(false);
		
		StringPanel panel = new StringPanel();//得到定制的面板
		con.add(panel);//將面板添加到內容窗格中
	}
}

/**
 *　這是繼承了JPanel面板類，它重載了繪制的方法
 */
class StringPanel extends JPanel
{
	public static final double WIDTH = 200;
	public static final double HEIGHT = 100;
	public static final double X = 100;
	public static final double Y = 100;
	
	public void paintComponent(Graphics g)
	{
		super.paintComponent(g);
		Graphics2D g2 = (Graphics2D)g;
		
		//繪制矩形
		Rectangle2D rec = new Rectangle2D.Double(X, Y, WIDTH, HEIGHT);
		g2.draw(rec);
		
		//得到矩形的中心坐標值
		double centerX = rec.getCenterX();
		double centerY = rec.getCenterY();
		
		//根據矩形的外框，繪制內接橢圓
		Ellipse2D e = new Ellipse2D.Double();
		e.setFrame(rec);
		g2.draw(e);
		
		//根據矩形的中心，繪制與長徑相切同心圓形
		Ellipse2D circle1 = new Ellipse2D.Double();
		circle1.setFrameFromCenter(centerX, centerY, centerX + WIDTH/2, centerY + WIDTH/2);
		g2.draw(circle1);
		
		//根據矩形的中心，繪制與短徑相切同心圓形
		Ellipse2D circle2 = new Ellipse2D.Double();
		circle2.setFrameFromCenter(centerX, centerY, centerX + HEIGHT/2, centerY + HEIGHT/2);
		g2.draw(circle2);
		
		//根據矩形的兩點繪制直線
		Line2D line = new Line2D.Double(X, Y, X + WIDTH, Y + HEIGHT);
		g2.draw(line);		
	}
}