fontinfo.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_02_01: fontInfo.jsp
	功能: 获取字符的精确信息
-->
<%@ 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);
		Font[] font = new Font[2];
		font[0] = new Font("方正粗宋简体", Font.PLAIN, 20);
		font[1] = new Font("华文隶书", Font.BOLD, 18);
		String title="欢迎来到Java Web图表编程的世界";
		String info="";

		int ascent, descent, fontHeight, leading, stringLength;
		for (int i= 0; i<font.length; i++)
		{
			g.setFont(font[i]);
			ascent = g.getFontMetrics().getAscent();
			descent = g.getFontMetrics().getDescent();
			fontHeight = g.getFontMetrics().getHeight();
			leading = g.getFontMetrics().getLeading();
			
			stringLength = g.getFontMetrics().stringWidth(title);

			info = "高度是: " + fontHeight + ", 上升值是: " + 
				   ascent + ", 下降值是: " + descent +  
				   ", 超出值是: " + leading;	
			
			g.drawString("当前字体:" + font[i].getName() + 
				         ", 字体信息:" , 10, 50 + i*100);
			g.drawString(info , 10, 80 + i* 100);
			g.drawString("字符串:\""+ title +"\"的长度是:"+ stringLength, 
				   10, 110 + i*100);
        }

		// 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.                                 *
 **************************************************************************/
%>