AJAX实现进度条

AJAX实现进度条 public class UploadListener implements OutputStreamListener { private HttpServletRequest request; private long delay = 0; private long startTime = 0; private int totalToRead = 0; private int totalBytesRead = 0; private int totalFiles = -1; public UploadListener(HttpServletRequest request, long debugDelay) { this.request = request; this.delay = debugDelay; totalToRead = request.getContentLength(); this.startTime = System.currentTimeMillis(); } public void start() { totalFiles ++; updateUploadInfo("start"); } public void bytesRead(int bytesRead) { totalBytesRead = totalBytesRead + bytesRead; updateUploadInfo("progress"); try { Thread.sleep(delay); } catch (InterruptedException e) { e.printStackTrace(); } } public void error(String message) { updateUploadInfo("error"); } public void done() { updateUploadInfo("done"); } private long getDelta() { return (System.currentTimeMillis() - startTime) / 1000; } private void updateUploadInfo(String status) { long delta = (System.currentTimeMillis() - startTime) / 1000; request.getSession().setAttribute("uploadInfo", new UploadInfo(totalFiles, totalToRead, totalBytesRead,delta,status)); } } ÉÏÃæµÄ?úÂëÖÐ??Ô,×?ÕßΪÁËÑÝÊ????ú?Ù×?ÉϵÄÏÔÊ?Ð??û??ÌØ?ð?ÓÈëÁËdebugDelay×öÑÓÊ???Àí??ÔÚʵ?ÊÓ?ÓÃÖÐ?ÉÒÔÉ??ý?? upload.jsp: <%@ page import="be.telio.mediastore.ui.upload.MonitoredDiskFileItemFactory" %> <%@ page import="be.telio.mediastore.ui.upload.UploadListener" %> <%@ page import="org.apache.commons.fileupload.FileItem" %> <%@ page import="org.apache.commons.fileupload.FileItemFactory" %> <%@ page import="org.apache.commons.fileupload.FileUploadException" %> <%@ page import="org.apache.commons.fileupload.servlet.ServletFileUpload" %> <%@ page contentType="text/html;charset=UTF-8" language="java" %> <%-- /* Licence: * Use this however/wherever you like, just don't blame me if it breaks anything. * * Credit: * If you're nice, you'll leave this bit: * * Class by Pierre-Alexandre Losson -- * email : plosson@users.sourceforge.net */ --%> <% UploadListener listener = new UploadListener(request, 30); // Create a factory for disk-based file items FileItemFactory factory = new MonitoredDiskFileItemFactory(listener); // Create a new file upload handler ServletFileUpload upload = new ServletFileUpload(factory); try { // process uploads .. upload.parseRequest(request); //....??ÀíÉÏ??ÎÄ?þ } catch (FileUploadException e) { e.printStackTrace(); //To change body of catch statement use File | Settings | File Templates. } %>