eclipse停找不到图片，请大神帮忙_Eclipse

eclipse下找不到图片，请大神帮忙！
我制作的类：
package samples.javabean;

import java.awt.Color;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;
import javax.imageio.stream.ImageOutputStream;
import javax.swing.JFrame;
import javax.swing.JScrollPane;

import org.jgraph.JGraph;
import org.jgraph.graph.DefaultCellViewFactory;
import org.jgraph.graph.DefaultGraphCell;
import org.jgraph.graph.DefaultGraphModel;
import org.jgraph.graph.DefaultPort;
import org.jgraph.graph.GraphConstants;
import org.jgraph.graph.GraphLayoutCache;
import org.jgraph.graph.GraphModel;

public class Graphic {
   String webroot;
   String filename;
   String random;
   public Graphic()
   {
   webroot="e:\\workspace\\DBtest\\res";
   filename="number.png";
   }

public String getFilename() {
return filename;
}
public void setFilename(String filename) {
this.filename = filename;
}

public String getRandom() {
return random;
}
public void setRandom(String random) {
this.random = random;
}

   public void paint()
   {
   GraphModel model=new DefaultGraphModel();
   GraphLayoutCache view=new GraphLayoutCache(model,new DefaultCellViewFactory());
   JGraph graph=new JGraph(model,view);
   DefaultGraphCell cell=new DefaultGraphCell(random);
   GraphConstants.setBounds(cell.getAttributes(),new Rectangle2D.Double(0,0,100,40));
   GraphConstants.setGradientColor(cell.getAttributes(),Color.orange);
   GraphConstants.setOpaque(cell.getAttributes(),true);
   DefaultPort port=new DefaultPort();
   cell.add(port);
   graph.getGraphLayoutCache().insert(cell);
   JFrame frame=new JFrame();
   frame.getContentPane().add(new JScrollPane(graph));
   frame.pack();
   frame.setVisible(false);

   try{
   File f=new File(webroot,filename);
   ImageOutputStream ios=ImageIO.createImageOutputStream(f);
   BufferedImage img=graph.getImage(graph.getBackground(),1);
   ImageIO.write(img,"png",ios);
   ios.flush();
   ios.close();
      }
       catch(IOException e)
       {
        e.printStackTrace();
       }

   }
}

调用的此类的jsp文件：

<%@ page language="java" contentType="text/html; charset=GB2312"
    pageEncoding="GB2312"%>
<%@ page import="samples.javabean.*" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GB2312">