drawarcs.java

本java源程序包括了大量的学习程序（共27章）方便大家学习

import java.awt.*;
import javax.swing.*;
public class DrawArcs extends JFrame
{
	public DrawArcs()
	{
	  super("Draw Arcs");
	  DrawPanel drawPanel = new DrawPanel();
	  Container content = getContentPane();  
	  //使用getContentPane()返回Container的对象，该对象中可以填入其他组件
	  content.add(drawPanel);
	  //在content对象中加入面板DrawPanel的对象drawPanel
		this.setSize(300, 170);
		this.setVisible(true);
	}
	public static void main(String[] args) 
	{
		DrawArcs application = new DrawArcs();
		application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	}
}
class DrawPanel extends JPanel
{	
	public void paintComponent(Graphics g)
	{    
	    g.setColor(Color.BLUE);
	    g.drawRect(15, 35, 80, 80);
        //绘制弧形，起始角度为0，弧形扫过的度数为360,
	    //边界矩形的左上角坐标为(15,35),宽度为80,高度为80
	    g.drawArc(15, 35, 80, 80, 0, 360);
	    
	    g.setColor(Color.BLUE);
	    g.drawRect(100, 35, 80, 80);
        //绘制弧形，起始角度为0，弧形扫过的度数为110,
	    //边界矩形的左上角坐标为(100,35),宽度为80,高度为80
	    g.drawArc(100, 35, 80, 80, 0, 110);
	    
	    g.setColor(Color.BLUE);
	    g.drawRect(185, 35, 80, 80);
        //绘制弧形，起始角度为0，弧形扫过的度数为-270,
	    //边界矩形的左上角坐标为(185,35),宽度为80,高度为80
	    g.drawArc(185, 35, 80, 80, 0, -270);
	    
	    //绘制实心弧形,即扇形
	    g.fillArc(15, 120, 80, 40, 0, 360);
	    g.fillArc(100, 120, 80, 40, 270, -90);
	    g.fillArc(185, 120, 80, 40, 0, -270);
	}   
}