transparentpie3d.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. 7.13_01: transparentPie3D.jsp
	功能: 基于Java2D的Web图表实例16: 透明3D饼图
-->
<%@ page language="java" contentType="image/png;charset=GB2312"
	import="java.awt.*"
	import="javax.imageio.*"
	import="java.awt.geom.*"
	import="java.awt.image.*"
	import="java.text.*"
%>
<%!
	// 绘制饼图的说明
	public void drawTips(String tips, Color color, Arc2D.Double arc2d, Graphics2D g2d)
	{	 
		 Arc2D.Double position = arc2d;

		 position.setAngleExtent(arc2d.getAngleExtent()/2);
		 position.x = arc2d.x - 15;
		 position.y = arc2d.y - 15;
		 position.width = arc2d.getWidth() + 50 ;
		 position.height = arc2d.getHeight() + 50;
		 Point2D.Double startPoint = 
			 (Point2D.Double)position.getStartPoint();
		 Point2D.Double endPoint = (Point2D.Double)position.getEndPoint();

		 g2d.setPaint(color);
		 
		 int stringLength = g2d.getFontMetrics().stringWidth(tips);
		 
		 if (endPoint.x <= arc2d.getCenterX())
			g2d.drawString(tips, (float)endPoint.x - stringLength, (float)endPoint.y);
		 else
			g2d.drawString(tips, (float)endPoint.x, (float)endPoint.y );
	}    
%>

<%
// 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();

// 打开反锯齿功能，用于平滑处理相关背景,图表标题及饼图
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
            RenderingHints.VALUE_ANTIALIAS_ON);

// 填充整个背景
g2d.setPaint(Color.WHITE);
g2d.fillRect(0, 0, width, height);

// 绘制阴影，由灰色渐进圆角矩形组成
GradientPaint grayGP = new GradientPaint(0, 0, Color.GRAY, 
	width, height, new Color(218, 214, 212), false);
g2d.setPaint(grayGP);
RoundRectangle2D.Float bgRR = 
	new RoundRectangle2D.Float(5, 5, width-5, height-5 , 50, 50);
g2d.fill(bgRR);

// 绘制渐进蓝色圆角矩形背景
GradientPaint blueGP = new GradientPaint(0, 0, new Color(252, 197, 113), 
	width/2, height/2, new  Color(255, 255, 169), true);
g2d.setPaint(blueGP);
g2d.fillRoundRect(0, 0, width - 5, height - 5, 50, 50);

// 绘制深蓝色圆角矩形轮廓
BasicStroke bs = new BasicStroke(1.2f);
g2d.setStroke(bs);
g2d.setPaint(new Color(55,71, 105));
g2d.drawRoundRect(0, 0, width -5, height -5, 50, 50);

// 绘制图表标题
String chartTitle = "编程类图书销售量统计3D饼图";
g2d.setColor(Color.BLACK);
g2d.setFont(new Font("经典繁颜体", Font.PLAIN, 30));
int stringLength = g2d.getFontMetrics().stringWidth(chartTitle);
g2d.drawString(chartTitle, (width - stringLength) / 2, 25 );

// 定义圆弧
Arc2D.Double arc2d = new Arc2D.Double();

double startAngle = 30.0, arcAngle = 0.0;
double rectWidth = 280.0, rectHeight = 235.0;
Point2D.Double p2d = new Point2D.Double((width - rectWidth)/2, 70.0);
int arcType = Arc2D.PIE;

// 声明绘制数据
String bookTitle[] = {"Python", "JAVA", "C#", "Perl", "PHP"};
Color color[] = new Color[5];
color[0] = new Color(99,99,0);
color[1] = new Color(255,169,66);
color[2] = new Color(33,255, 66);
color[3] = new Color(33,0,255);
color[4] = new Color(255,0,66);

double bookSales[] = new double[5];
double totalSales = 0.0 ;
double proportion = 0.0;

// 定义厚度
int thickness = 25;

for (int i=0; i< bookSales.length; i++)
{
	bookSales[i] = 1 +  Math.random() * 99;
	totalSales += bookSales[i];
}

// 定义圆弧的起始角度
startAngle = 30 ;

for (int counter = thickness; counter > 0; counter--)
{
  for(int i = 0 ; i < bookTitle.length; i++)
  {   
	// 打开反锯齿功能，用于平滑处理饼图
	g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
            RenderingHints.VALUE_ANTIALIAS_ON);
	
	// 创建AlphaComposite对象，并设定透明度
    AlphaComposite ac = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, .3f);
	g2d.setComposite(ac);
	arcAngle = bookSales[i]*360 / totalSales;
	proportion = bookSales[i]/totalSales * 100 ;

	if (counter == 1 || counter == thickness)
	{
		g2d.setColor(color[i]);
		
		arc2d = new Arc2D.Double(p2d.x, p2d.y + counter, rectWidth, 
		rectHeight, startAngle, arcAngle, arcType);
		
		// 填充圆弧
		g2d.fill( arc2d) ;
		
		// 取消透明色,用于绘制饼图的轮廓
		ac = AlphaComposite.getInstance(AlphaComposite.SRC_OVER);
		g2d.setComposite(ac);

		// 描绘圆弧的轮廓
		BasicStroke s = new BasicStroke(1.2f);
		g2d.setStroke(s);
		g2d.setColor(Color.GRAY);
		g2d.draw(arc2d) ;
	}
	else
	{
		arc2d = new Arc2D.Double(p2d.x, p2d.y + counter, rectWidth, 
			rectHeight, startAngle, arcAngle, arcType);
		
		g2d.setColor( color[i].darker());
		
		// 填充圆弧
		g2d.draw( arc2d) ;
	}

	// 更新圆弧的起始角度
	startAngle += arcAngle;

	// 格式化浮点数的输出格式
	DecimalFormat twoDigits = new DecimalFormat("0.00");
	g2d.setFont(new Font("Courier New", Font.PLAIN, 12));

	if ( counter == 1)
	{
		// 取消透明色,用于绘制饼图的说明文字
		ac = AlphaComposite.getInstance(AlphaComposite.SRC_OVER);
		g2d.setComposite(ac);
		
		// 重新关闭反锯齿功能，用于绘制饼图的说明文字
		g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
				RenderingHints.VALUE_ANTIALIAS_OFF);

		// 绘制说明文字
		drawTips(bookTitle[i] + " " + twoDigits.format(proportion) + "%",
			Color.BLACK, arc2d, g2d);
	}
  }
}
// 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.                                 *
 **************************************************************************/
%>