multilinelayout.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. 7.11_03: multiLineLayout.jsp
	功能: 基于Java2D的Web图表实例14: 文本自动分行显示
-->
<%@ page language="java" contentType="image/png;charset=GB2312"
	import="java.awt.*"
	import="javax.imageio.*"
	import="java.awt.geom.*"
	import="java.awt.image.*"
	import="java.awt.font.*"
	import="java.text.*"
%>

<%
		// 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);
		g2d.setColor(Color.BLACK);
        
        Font font = new Font("华文隶书", Font.BOLD + Font.ITALIC, 35);
		String text = "欢迎来到《精通Java Web动态图表编程》。这本书展示了如何使用" +
					  "Java Applet、Servlet、Java Server Pages (JSP) 及JavaBean来" + 
					  "帮助你开发奇妙的Web图表应用程序 - 以一种跨平台的、小巧的和" +
					  "结构清晰的模式在Web上生成动态图表。               " + 
					  "作者:钟京馗、唐桓" ;

		AttributedString as = new AttributedString(text);
        as.addAttribute(TextAttribute.FONT, font);
        AttributedCharacterIterator aci = as.getIterator();
        
        FontRenderContext frc = g2d.getFontRenderContext();
        LineBreakMeasurer lbm = new LineBreakMeasurer(aci, frc);

	
		float x = 10.f;
		float y = 10.f;
		
		// 定义文本分行的宽度
		float wrappingWidth = 450;

        // 绘制文本，如果文本的长度超过wrappingWidth的值，则进行分行处理
		while (lbm.getPosition() < aci.getEndIndex()) 
		{
			  TextLayout textLayout = lbm.nextLayout(wrappingWidth);
			  y += textLayout.getAscent();
			  textLayout.draw(g2d, x, y);
			  
			  y += textLayout.getDescent() + textLayout.getLeading();
        }

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