drawarcs.jsp

提供 精通Java Web动态图表编程 一书的源代码, 大家赶快下载呀

<!--
	Fig. 6.04_05_01: drawArcs.jsp
	功能:绘制圆弧
-->
<%@ page language="java" contentType="image/png;charset=GB2312"
	import="java.awt.image.*"
	import="java.awt.*"
	import="javax.imageio.*"
%>

<%
		// 清空缓冲区
		response.reset();

		// 注意这里的MIME类型
		response.setContentType("image/png");

		// 创建一个 640X480 的图像
		int width = 640, height = 480;

		BufferedImage image = new BufferedImage(width, height,
		  BufferedImage.TYPE_INT_RGB);
		Graphics g = image.getGraphics();

		// 填充背景
		g.setColor(Color.WHITE);
		g.fillRect(0, 0, width, height);

		g.setColor(Color.BLACK);
		
        //设置字体
        g.setFont(new Font("汉真广标", Font.PLAIN, 35));
        g.drawString("圆弧的画法", 10, 40);

        // 绘制浅灰色矩形
        g.setColor(Color.LIGHT_GRAY);
        g.drawRect(10, 60, 150, 120);
        g.drawRect(210, 60, 120, 120);
        g.drawRect(10, 210, 150, 120);
        g.drawRect(210, 210, 120, 120);

        g.setColor(Color.BLUE);

        //绘制空心圆弧1		
        g.drawArc(10, 60, 150, 120, 0, 360);

        // 绘制空心圆弧2
        g.drawArc(210, 60, 120, 120, 90, 270);

        g.setColor(Color.RED);

        //绘制空心圆弧3
        g.drawArc(10, 210, 150, 120, 30, - 150);

        // 绘制空心圆弧4
        g.drawArc(210, 210, 120, 120,  - 90,  - 270);

		// 绘制浅灰色矩形
        g.setColor(Color.LIGHT_GRAY);
        g.drawRect(350, 60, 150, 120);
        g.drawRect(510, 60, 120, 120);
        g.drawRect(350, 210, 150, 120);
        g.drawRect(510, 210, 120, 120);

        g.setColor(Color.BLUE);

        // 绘制实心圆弧1		
        g.fillArc(350, 60, 150, 120, 0, 360);

        // 绘制实心圆弧2
        g.fillArc(510, 60, 120, 120, 90, 270);

        g.setColor(Color.RED);

        // 绘制实心圆弧3
        g.fillArc(350, 210, 150, 120, 30,  - 150);

        // 绘制实心圆弧4
        g.fillArc(510, 210, 120, 120,  - 90,  - 270);
		
		// 部署图形
		g.dispose();

		// 利用ImageIO类的write方法对图像进行编码
		ServletOutputStream sos = response.getOutputStream();
		ImageIO.write(image, "PNG", sos);
		sos.close();
%>


<%
/**************************************************************************
 * (C) Copyright 2004-2005 by Jingkui Zhong(钟京馗) and Huan Tang(唐桓).  *
 * All Rights Reserved.                                                   *
 *                                                                        *
 * DISCLAIMER: The authors of this code have used their                   *
 * best efforts in preparing the code. These efforts include the          *
 * development, research, and testing of the theories and programs        *
 * to determine their effectiveness. The authors and publisher make       *
 * no warranty of any kind, expressed or implied, with regard to these    *
 * programs or to the documentation contained in these codes. The authors *
 * shall not be liable in any event for incidental or consequential       *
 * damages in connection with, or arising out of, the furnishing,         *
 * performance, or use of these programs.                                 *
 **************************************************************************/

%>