利用JAVA绘图动态生成图片发送到客户端IE

package com.gepower.ps.eps.topissuesadmin.common;
import java.awt.*;
import java.awt.geom.Line2D;
import java.awt.image.BufferedImage;
import java.io.IOException;
import javax.imageio.IIOException;
import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.*;
import org.apache.commons.lang.NumberUtils;
/**
*
* <p>
* Title: TIMT
* </p>
* <p>
* Description: 2008-03
* </p>
* <p>
* Copyright: Copyright (c) 2006
* </p>
* <p>
* Company: TCS
* </p>
*
* @author Xujin.Jiao
* @version 4.0
*/
public class CinScoreImgServlet extends HttpServlet {
public static final long serialVersionUID = 123888839L;
    public CinScoreImgServlet() {
    }
    public void init() throws ServletException {
        super.init();
    }
    public void destroy() {
        super.destroy();
    }
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
                   throws ServletException, IOException {
        process(request, response);
    }
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
                   throws ServletException, IOException {
        process(request, response);
    }
    protected void process(HttpServletRequest request, HttpServletResponse response)
                   throws ServletException, IOException {
     boolean drawTriangle = true;
  int width = TopIssueAdminConstants.CIN_IMAGE_WIDTH;
  int height = TopIssueAdminConstants.CIN_IMAGE_HEIGHT;
        int halfTrag = (int)Math.round(height / Math.sqrt(3d));
  int axisWidth = width - halfTrag;
  int cinScore = 0;
  int tragXpos = axisWidth;
  String cinScoreStr = request.getParameter("cinScore");
  if (null != cinScoreStr && cinScoreStr.trim().length() > 0) {
   try {
    if (!NumberUtils.isNumber(cinScoreStr)) {
     drawTriangle = false;
    } else if (Integer.parseInt(cinScoreStr) < 0) {
     drawTriangle = false;
    } else {
        cinScore = Integer.parseInt(cinScoreStr);
        tragXpos = axisWidth - (int)Math.round((cinScore * axisWidth) / TopIssueAdminConstants.MAX_CIN_SCORE);
    }
   } catch (Exception e) {
    drawTriangle = false;
    EPSLogger.debug("process() : Error in CinScoreImgServlet : "+ e.getMessage());
   }
  }
  BufferedImage bi = new BufferedImage(width, height,
                                 BufferedImage.TYPE_INT_RGB);
  Graphics2D g2 = (Graphics2D)bi.getGraphics();
  g2.setBackground(Color.WHITE);
  g2.clearRect(0, 0, width, height);
     g2.setColor(Color.black);
     g2.drawLine(0, 0, 0, height);
     g2.drawLine(axisWidth / 2, 0, axisWidth / 2, height);
     g2.drawLine(axisWidth, 0, axisWidth, height);
     float dashes[] = {10, 2};
     g2.setPaint(Color.black);
     g2.setStroke(new BasicStroke(1, BasicStroke.CAP_BUTT,
                            BasicStroke.JOIN_MITER,
                                  10, dashes, 0 ));
     g2.draw(new Line2D.Double(0, height / 2, axisWidth, height / 2));
     if (drawTriangle) {
   int xValues[] = {tragXpos, tragXpos + halfTrag, tragXpos - halfTrag};
   int yValues[] = {0, height, height};
   g2.setColor(Color.CYAN);
   g2.fillPolygon(xValues, yValues, 3);
     }
        response.setContentType("image/jpg");
        try {
      ImageIO.write(bi, "jpg", response.getOutputStream());
        } catch(IIOException ex) {
         EPSLogger.debug("process() : Error in CinScoreImgServlet : "+ ex.getMessage());
        }
    }
}


在web.xml中加上这个:
==================================================================
<servlet>
    <servlet-name>DisplayCinImage</servlet-name>
    <servlet-class>com.gepower.ps.eps.topissuesadmin.common.CinScoreImgServlet</servlet-class>
</servlet>

<servlet-mapping>
    <servlet-name>DisplayCinImage</servlet-name>
    <url-pattern>/servlet/DisplayCinImage</url-pattern>
</servlet-mapping>


JSP中这样使用:
===============================================================
<td align="center">
  <img src="<%=request.getContextPath()%>/servlet/DisplayCinImage?cinScore=<%=roundOff(tMB.getCinScore())%>" alt="CIN Score=<%=roundOff(tMB.getCinScore())%>" />
</td>

效果图: