rotation.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. 7.9_03: rotation.jsp
	功能: 图形对象的旋转
-->
<%@ page language="java" contentType="image/png;charset=GB2312"
	import="java.awt.*"
	import="javax.imageio.*"
	import="java.awt.geom.*"
	import="java.awt.image.*"
%>

<%
// 清空缓冲区
response.reset();

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

// 创建一个 500X375 的图像
int width = 500, height = 375;

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

// 创建Java2D对象
Graphics2D g2d = image.createGraphics();

// 填充背景
g2d.setColor(Color.WHITE);
g2d.fillRect(0, 0, width, height);

String s = "精通 Java Web图表编程";
Font f = new Font("宋体", Font.BOLD, 16);
Color[] colors = {Color.BLUE, Color.RED};
g2d.setFont(f);

// 平移原点到图形环境的中心
g2d.translate(width/2, height/2);
        
// 旋转文本
for (int i=0; i<12; i++) 
{
	g2d.rotate(30*Math.PI/180);
	g2d.setPaint(colors[i%2]);
	g2d.drawString(s, 0, 0);
}

// 部署图形
g2d.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.                                 *
 **************************************************************************/
%>