求助，为什么这个FLEX和SERVLET上传图片总是出错！！
FLEX端得代码：
<?xml version="1.0" encoding="utf-8"?><mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" xmlns="*" creationComplete="init();"><mx:Script><![CDATA[import flash.net.FileReference;import mx.controls.Alert;import mx.events.CloseEvent;import flash.events.*;private var file: FileReference;private function init(): void{Security.allowDomain("*");file = new FileReference();file.addEventListener(ProgressEvent.PROGRESS, onProgress);file.addEventListener(Event.SELECT, onSelect);}private function upload(): void{var imageTypes:FileFilter = new FileFilter("Images (*.jpg, *.jpeg, *.png)", "*.jpg;*.jpeg;*.png");var allTypes:Array = new Array(imageTypes);file.browse(allTypes);file.browse();}private function onSelect(e: Event): void{Alert.show("上传 " + file.name + " (共 "+Math.round(file.size)+" 字节)?","确认上传",Alert.YES|Alert.NO,null,proceedWithUpload);}private function onProgress(e: ProgressEvent): void{lbProgress.text = " 已上传 " + e.bytesLoaded + " 字节，共 " + e.bytesTotal + " 字节";var proc: uint = e.bytesLoaded / e.bytesTotal * 100;bar.setProgress(proc, 100);bar.label= "当前进度: " + " " + proc + "%";}private function proceedWithUpload(e: CloseEvent): void{if (e.detail == Alert.YES){var request: URLRequest = new URLRequest("http://pc2010032013pib:8080/Upload/servlet/FileUploadServlet");try {file.upload(request);} catch (error:Error) {trace("上传失败");}}}]]></mx:Script><mx:Canvas width="100%" height="100%" x="10" y="170" fontSize="15"><mx:VBox width="100%" horizontalAlign="center"><mx:Label id="lbProgress" text="上传"/><mx:ProgressBar id="bar" labelPlacement="bottom" themeColor="#F20D7A"minimum="0" visible="true" maximum="100" label="当前进度: 0%" direction="right" mode="manual" width="200"/><mx:Button label="上传文件" click="upload();"/> </mx:VBox></mx:Canvas></mx:Application>import java.io.*;import java.util.*;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.apache.commons.fileupload.FileItem;import org.apache.commons.fileupload.FileUploadException;import org.apache.commons.fileupload.disk.DiskFileItemFactory;import org.apache.commons.fileupload.servlet.ServletFileUpload;/** * * @author crystal */public class FileUploadServlet extends HttpServlet { /** * Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods. * @param request servlet request * @param response servlet response */ // 定义文件的上传路径 private String uploadPath = "E:\\upload\\";// 限制文件的上传大小 private int maxPostSize = 1024 * 1024 * 1024; public FileUploadServlet() { super(); } public void destroy() { super.destroy(); } protected void processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { System.out.println("Access !"); response.setContentType("text/html;charset=UTF-8"); PrintWriter out = response.getWriter(); DiskFileItemFactory factory = new DiskFileItemFactory(); factory.setSizeThreshold(4096); ServletFileUpload upload = new ServletFileUpload(factory); upload.setSizeMax(maxPostSize); try { [color=#FF0000] List fileItems = upload.parseRequest(request);[/color] Iterator iter = fileItems.iterator(); while (iter.hasNext()) { FileItem item = (FileItem) iter.next(); if (!item.isFormField()) { String name = item.getName(); System.out.println(name); try { item.write(new File(uploadPath + name)); [color=#00FF00] // SaveFile s = new SaveFile(); // s.saveFile(name);[/color] } catch (Exception e) { e.printStackTrace(); } } } } catch (FileUploadException e) { e.printStackTrace(); System.out.println(e.getMessage() + "结束"); } } // <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code."> /** * Handles the HTTP <code>GET</code> method. * @param request servlet request * @param response servlet response */ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { processRequest(request, response); } /** * Handles the HTTP <code>POST</code> method. * @param request servlet request * @param response servlet response */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { processRequest(request, response); }}