struts2：上传多个文件时实现带进度条、进度详细信息的示范详解编程语言

上一篇文章讲了上传单个文件与上传多个文件（属性驱动）的例子。本例是上传多个文件（属性驱动），并且显示进度条、进度详细信息的示范。

在文件上传选择界面，允许用户增加、删除选择的文件，且只能上传指定类型的文件； 在文件上传选择界面，不允许用户直接输入文件名，必须通过按钮选择文件； 上传过程中，利用jQuery的progressbar的widget插件显示当前上传进度的百分比； 上传过程中，利用一个DIV显示上传进度的详细信息。

1. 设计上传的JSP页面（uploadTest3.jsp）
1.1 关于jQuery的进度条，有三段代码
1.2 轮询后台查询进度
2. 显示处理结果的JSP页面（showResult2.jsp）
3. 创建Action类及属性驱动类
4. 创建实现ProgressListener接口的类、创建实现查询进度的Action类、创建传递进度信息的实体类
5. 将上传进度类与Struts2关联
5.1 拷贝JakartaMultiPartRequest类并做适当修改
5.2 替换Struts2默认的上传关联类（修改struts.xml）
6. 修改struts.xml，加入Action配置
7. 设置上传文件相关参数（struts.properties）
8. 测试

1. 设计上传的JSP页面（uploadTest3.jsp）

对比于上一篇文章中的uploadTest2.jsp文件，加入了如下功能：

增加、删除上传文件，只能上传指定类型的文件；只能通过按钮选择文件，不可能直接输入文件名。方法：file_change()/remove_file()/insertFile()/f()等。 增加调用jQuery的AJAX方法轮询后台上传进度信息并显示在前台。方法：refreshProcessBar()/refreshProcessBarCallBack()/及function()初始化进度条等。 增加了引用jQuery进度条（progressbar）的相关CSS与JS文件：jquery.js/jquery.ui.core.js/jquery.ui.widget.js/jquery.ui.progressbar.js；至于CSS文件，为简单起见，我直接将示范目录themes/base/拷贝到项目中。

 %@ page language="java" import="java.util.*" pageEncoding="utf-8" % 

 %@ page isELIgnored="false" % 

 %@ taglib uri="/struts-tags" prefix="s" % 

 html xmlns="http://www.w3.org/1999/xhtml" 

 head 

 meta http-equiv="Content-Type" content="text/html; charset=utf-8" / 

 title 多文件上传，显示进度条实例 /title 

 style type="text/css" 

 !-- 

body, td, th { 

 font-size: 9pt; 

 /style 

 !--参考：http://api.jqueryui.com/progressbar/-- 

 link rel="stylesheet" href="../../css/themes/base/jquery.ui.all.css" 

 script src="../../js/jquery.js" /script 

 script src="../../js/jquery.ui.core.js" /script 

 script src="../../js/jquery.ui.widget.js" /script 

 script src="../../js/jquery.ui.progressbar.js" /script 

 script type="text/javascript" 

 // 下面这三个函数是生成与刷新进度条、进度详细信息的 

 // 初始化进度条 

 $(function() { 

 $("#progressbar").progressbar({ 

 value: 0 

 }); 

 }); 

 // 调用查询进度信息接口 

 function refreshProcessBar(){ 

 $.get("getState.action?timestamp=" + new Date().getTime(), function(data){ 

 refreshProcessBarCallBack(data); 

 }, xml); 

 // 查询进度信息接口回调函数 

 function refreshProcessBarCallBack(returnXMLParam){ 

 var returnXML = returnXMLParam; 

 var percent = $(returnXML).find(percent).text() 

 var showText = "进度是：" + percent + "%"; 

 showText = showText + "/n当前上传文件大小为：" + $(returnXML).find (uploadByte).text(); 

 showText = showText + "/n上传文件总大小为：" + $(returnXML).find (fileSizeByte).text(); 

 showText = showText + "/n当前上传文件为第：" + $(returnXML).find (fileIndex).text() + "个"; 

 showText = showText + "/n开始上传时间：" + $(returnXML).find (startTime).text(); 

 // 刷新进度详细信息 

 $(#progressDetail).empty(); 

 $(#progressDetail).text(showText); 

 // 刷新进度条 

 $("#progressbar").progressbar("option", "value", parseInt(percent)); 

 setTimeout("refreshProcessBar()", 1000); 

 // 下面这三个函数是控制添加、删除、修改附件的（允许增加、删除附件，只允许指定后缀的文件被选择等） 

 var a = 0; 

 function file_change(){ 

 //当文本域中的值改变时触发此方法 

 var postfix = this.value.substring(this.value.lastIndexOf(".") + 1).toUpperCase(); 

 //判断扩展是否合法 

 if (postfix == "JPG" || postfix == "GIF" || postfix == "PNG" || postfix == "BMP" || 

 postfix == "RAR" || 

 postfix == "ZIP" || 

 postfix == "TXT" || 

 postfix == "GHO" || 

 postfix == "PDF") { 

 else { 

 //如果不合法就删除相应的File表单及br标签 

 alert("您上传的文件类型不被支持，本系统只支持JPG,GIF,PNG,BMP,RAR,ZIP,TXT文件！"); 

 var testtest = $(this).attr(id); 

 testtest = # + testtest; 

 var sub_file = $(testtest); 

 var next_a_ele = sub_file.next();//取得a标记 

 var br1_ele = $(next_a_ele).next();//取得回车 

 var br2_ele = $(br1_ele).next();//取得回车 

 $(br2_ele).remove();//删除回车 

 $(br1_ele).remove();//删除回车 

 $(next_a_ele).remove();//删除a标签 

 $(sub_file).remove(); 

 //删除文本域，因为上传的文件类型出错，要删除动态创建的File表单 

 return; 

 function remove_file(){//删除File表单域的方法 

 //删除表单 

 var testtest = $(this).val(); 

 testtest = # + testtest; 

 var sub_file = $(testtest); 

 var next_a_ele = sub_file.next();//取得a标记 

 var br1_ele = $(next_a_ele).next();//取得回车 

 var br2_ele = $(br1_ele).next();//取得回车 

 $(br2_ele).remove();//删除回车 

 $(br1_ele).remove();//删除回车 

 $(next_a_ele).remove();//删除a标签 

 $(sub_file).remove();//删除File标记 

 function f(){ 

 //方法名为f的主要作用是不允许在File表单域中手动输入文件名，必须单击“浏览”按钮 

 return false; 

 function insertFile(){ 

 //新建File表单 

 var file_array = document.getElementsByTagName("input"); 

 var is_null = false; 

 //循环遍历判断是否有某一个File表单域的值为空 

 for (var i = 0; i file_array.length; i++) { 

 if (file_array[i].type == "file" file_array[i].name.substring(0, 15) == "fileUploadTools") { 

 if (file_array[i].value == "") { 

 alert("某一附件为空不能继续添加"); 

 is_null = true; 

 break; 

 if (is_null) { 

 return; 

 a++; 

 //新建file表单的基本信息 

 var new_File_element = $( input ); 

 new_File_element.attr(type, file); 

 new_File_element.attr(id, uploadFile + a); 

 new_File_element.attr(name, fileUploadTools.uploadFile); 

 new_File_element.attr(size, 55); 

 new_File_element.keydown(f); 

 new_File_element.change(file_change); 

 $(#fileForm).append(new_File_element); 

 //新建删除附件的a标签的基本信息 

 var new_a_element = $( a ); 

 new_a_element.html("删除附件"); 

 new_a_element.attr(id, "a_" + new_File_element.name); 

 new_a_element.attr(name, "a_" + new_File_element.name); 

 new_a_element.val($(new_File_element).attr(id)); 

 new_a_element.attr(href, "#"); 

 new_a_element.click(remove_file); 

 $(#fileForm).append(new_a_element); 

 var new_br_element = $(" br "); 

 $(#fileForm).append(new_br_element); 

 var new_br_element = $(" br "); 

 $(#fileForm).append(new_br_element); 

 // 提交表单，提交时触发刷新进度条函数 

 function submitForm(){ 

 setTimeout("refreshProcessBar()", 1000); 

 return true; 

 /script 

 /head 

 body 

 br/ 

 s:form action="uploadT2" method="post" enctype="multipart/form-data" onsubmit="return submitForm()" 

 table width="818" border="1" 

 td width="176" 

 div align="center" 

 用户账号 

 /div 

 /td 

 td width="626" 

 input type="text" name="fileUploadTools.username" / 

 /td 

 /tr 

 div align="center" 

 用户附件 

 br/ 

 a href="javascript:insertFile()" 添加附件 /a 

 /div 

 /td 

 td id="fileForm" 

 br/ 

 /td 

 /tr 

 /table 

 input type="submit" value="开始上传..." / 

 /s:form 

 br/ 

 div id="progressbar" /div 

 br/ 

 div id="progressDetail" 

 p 进度详细信息显示于此...... /p 

 /div 

 /body 

 /html 

因为代码太长，所以缩起来了。

1.1 关于jQuery的进度条，有三段代码

引入CSS及JS文件

需要注意jquery.ui.all.css这个CSS文件会引用其它CSS文件，然后没止境的引用下去，所以，最好的办法，拷贝整个themes/base目录到项目中最好。

themes/base目录位于jquery-ui-1.10.3.zip包中。

progressbar的API官网：http://api.jqueryui.com/progressbar/

 link rel="stylesheet" href="../../css/themes/base/jquery.ui.all.css" 

 script src="../../js/jquery.js" /script 

 script src="../../js/jquery.ui.core.js" /script 

 script src="../../js/jquery.ui.widget.js" /script 

 script src="../../js/jquery.ui.progressbar.js" /script 

初始化进度条

 // 初始化进度条 

 $(function() { 

 $("#progressbar").progressbar({ 

 value: 0 

 }); 

 });

更新进度条

 // 刷新进度条 

 $("#progressbar").progressbar("option", "value", parseInt(percent));

1.2 轮询后台查询进度

表单提交时，触发refreshProcessBar()方法，回调refreshProcessBarCallBack()方法，然后再触发refreshProcessBar()方法,,,,,,， 这样可以实时查询上传进度，并更新前台页面。

2. 显示处理结果的JSP页面（showResult2.jsp）

这个页面就是上一篇文章中的页面，一模一样的。为缩小篇幅，代码缩起来。

 %@ page language="java" import="java.util.*" pageEncoding="utf-8"% 

 %@ page isELIgnored="false"% 

 %@ taglib uri="/struts-tags" prefix="s"% 

 !DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 

 html 

 body 

 您上传的文件名列表： 

 br/ 

 !--对Action中对象（fileUploadTools）包含的数组（uploadFileFileName）的遍历-- 

 s:iterator value="fileUploadTools.uploadFileFileName" status="st" 

 s:iterator value="fileUploadTools.uploadFileFileName[#st.index]" 

 s:property / 

 br/ 

 /s:iterator 

 /s:iterator 

 br / 

 /body 

 /html 

3. 创建Action类及属性驱动类

UploadTest2Action.java

这个Action类与上一篇文章中的Action类是一模一样的，为缩小篇幅，代码缩起来。

package com.clzhang.struts2.demo12; 

import java.io.IOException; 

import com.opensymphony.xwork2.ActionSupport; 

public class UploadTest2Action extends ActionSupport { 

 public static final long serialVersionUID = 1; 

 // 声明封装了File上传的FileUploadTools类的实例 

 // FileUploadTools类也封装了上传的属性及get和set方法 

 private FileUploadTools fileUploadTools = new FileUploadTools(); 

 public FileUploadTools getFileUploadTools() { 

 return fileUploadTools; 

 public void setFileUploadTools(FileUploadTools fileUploadTools) { 

 this.fileUploadTools = fileUploadTools; 

 @Override 

 public String execute() throws IOException { 

 fileUploadTools.beginUpload(); 

 return SUCCESS; 

}

FileUploadTools.java

这个属性代码类与上一篇文章中的Action类也是一模一样的，为缩小篇幅，代码缩起来。

package com.clzhang.struts2.demo12; 

import java.io.File; 

import java.io.IOException; 

import java.text.SimpleDateFormat; 

import java.util.Date; 

import org.apache.commons.io.FileUtils; 

import org.apache.struts2.ServletActionContext; 

public class FileUploadTools { 

 private String username; 

 private File uploadFile[];// 上传的文件是数组类型 

 private String uploadFileFileName[];// 文件名是数组类型 

 private String uploadFileContentType[]; 

 public String getUsername() { 

 return username; 

 public void setUsername(String username) { 

 this.username = username; 

 // 上传的ContentType文件类型也是数组类型 

 // 必须要加上对ContentType的声明，否则会出现异常 

 public String[] getUploadFileContentType() { 

 return uploadFileContentType; 

 public void setUploadFileContentType(String[] uploadFileContentType) { 

 this.uploadFileContentType = uploadFileContentType; 

 public File[] getUploadFile() { 

 return uploadFile; 

 public void setUploadFile(File[] uploadFile) { 

 this.uploadFile = uploadFile; 

 public String[] getUploadFileFileName() { 

 return uploadFileFileName; 

 public void setUploadFileFileName(String[] uploadFileFileName) { 

 this.uploadFileFileName = uploadFileFileName; 

 public String beginUpload() throws IOException { 

 System.out.println("用户名：" + username); 

 String targetDirectory = ServletActionContext.getServletContext().getRealPath("/upload"); 

 for (int i = 0; i uploadFile.length; i++) { 

 File target = new File(targetDirectory, new SimpleDateFormat("yyyy_MM_dd_HH_mm_ss") 

 .format(new Date()).toString() + System.nanoTime() + uploadFileFileName[i]); 

 FileUtils.copyFile(uploadFile[i], target); 

 return "success"; 

}

4. 创建实现ProgressListener接口的类、创建实现查询进度的Action类、创建传递进度信息的实体类

这个是查询进度信息的核心。

State类是一个保存进度信息的实体类，属性包括：uploadByte上传了多少字节，fileSizeByte文件总大小，fileIndex正在上传第几个文件等等； FileUploadListener类是一个实现ProgressListener接口的类，会在上传文件时，将接收到的相关信息存储到State类中； GetState是一个Action类，是将State当前状态返回给前台的接口，由前台AJAX调用，所以execute()方法返回null即可。

State.java

package com.clzhang.struts2.demo12; 

import java.text.NumberFormat; 

import java.text.SimpleDateFormat; 

import java.util.Date; 

public class State { 

 private long uploadByte; //已经上传的字节数，单位：字节 

 private long fileSizeByte; //所有文件的总长度，单位：字节 

 private int fileIndex; //正在上传第几个文件 

 private long startTime; //开始上传的时间，用于计算上传速度等 

 private int percent; // 上传百分比 

 private static final SimpleDateFormat SIMPLEFORMAT = new SimpleDateFormat("HH:mm:ss"); 

 public State() { 

 startTime = System.currentTimeMillis(); 

 percent = 0; 

 // 从State状态类中取得状态的字符串，用字符串的形式拼成XML文件内容 

 public synchronized String getStateString() { 

 StringBuilder sb = new StringBuilder(" info "); 

 sb.append(" uploadByte " + NumberFormat.getInstance().format(uploadByte) + " /uploadByte "); 

 sb.append(" fileSizeByte " + NumberFormat.getInstance().format(fileSizeByte) + " /fileSizeByte "); 

 sb.append(" fileIndex " + fileIndex + " /fileIndex "); 

 sb.append(" percent " + percent + " /percent "); 

 sb.append(" startTime " + SIMPLEFORMAT.format(startTime) + " /startTime "); 

 sb.append(" /info "); 

 return sb.toString(); 

 public synchronized void setState(long uploadByte, long fileSizeByte, int fileIndex) { 

 this.uploadByte = uploadByte; 

 this.fileSizeByte = fileSizeByte; 

 this.fileIndex = fileIndex; 

 if ((Long.valueOf(uploadByte) * 100 / Long.valueOf(fileSizeByte) = 100)) { 

 // 生成当前上传进度的公式，加入判断条件的含义在于不需要重复计算 

 percent = (int)(Long.valueOf(uploadByte) * 100 / Long.valueOf(fileSizeByte)); 

}

FileUploadListener.java

package com.clzhang.struts2.demo12; 

import javax.servlet.http.HttpServletRequest; 

import javax.servlet.http.HttpSession; 

import org.apache.commons.fileupload.ProgressListener; 

public class FileUploadListener implements ProgressListener { 

 // 声明一个HttpSession，目的是把State对象放到这个HttpSession中 

 private HttpSession session; 

 // 此构造函数由MyJakartaMultiPartRequest.java类parseRequest()方法调用 

 public FileUploadListener(HttpServletRequest request) { 

 super(); 

 session = request.getSession(); 

 public void update(long uploadByte, long fileSizeByte, int fileIndex) { 

 if (fileSizeByte == -1) { 

 // 如果上传的大小为-1则上传已经完成 

 System.out.println("上传文件结束！"); 

 } else { 

 if (session.getAttribute("uploadState") == null) { 

 // 如果为空就new一个State对象并设置里面的文本内容 

 State state = new State(); 

 state.setState(uploadByte, fileSizeByte, (fileIndex - 1)); 

 session.setAttribute("uploadState", state); 

 } else { 

 // 如果session中有uploadState对象就取出来，然后设置里面文本内容 

 State state = (State) session.getAttribute("uploadState"); 

 state.setState(uploadByte, fileSizeByte, (fileIndex - 1)); 

}

GetState.java

package com.clzhang.struts2.demo12; 

import java.io.IOException; 

import org.apache.struts2.ServletActionContext; 

public class GetState { 

 public String execute() throws IOException { 

 // 从session中取得名称为uploadState的State对象 

 State tempState = (State) ServletActionContext.getRequest().getSession() 

 .getAttribute("uploadState"); 

 // 设置编码为utf-8 

 ServletActionContext.getResponse().setCharacterEncoding("utf-8"); 

 // 设置响应的格式为XML 

 ServletActionContext.getResponse().setContentType("text/xml"); 

 // 用out对象输出xml代码头 

 ServletActionContext.getResponse().getWriter() 

 .print(" ?xml version=1.0 encoding=" + "utf-8" + " ? "); 

 // 用out对象输出xml代码体 

 ServletActionContext.getResponse().getWriter().print(tempState.getStateString()); 

 return null; 

}

5. 将上传进度类与Struts2关联

需要替换掉Struts2封装的上传外包类，以使fileUpload与我们上面的监听器绑定起来。

5.1 拷贝JakartaMultiPartRequest类并做适当修改

将org.apache.struts2.dispatcher.multipart.JakartaMultiPartRequest类的源代码拷贝到项目中，更改如下代码：

import org.apache.struts2.dispatcher.multipart.MultiPartRequest; 

 private List FileItem parseRequest(HttpServletRequest servletRequest, String saveDir) throws FileUploadException { 

 DiskFileItemFactory fac = createDiskFileItemFactory(saveDir); 

 ServletFileUpload upload = new ServletFileUpload(fac); 

 upload.setProgressListener(new FileUploadListener(servletRequest));// 设置上传进度的监听 

 upload.setSizeMax(maxSize); 

 return upload.parseRequest(createRequestContext(servletRequest)); 

 }

注意代码中的upload.setProgressListener(new FileUploadListener(servletRequest));行，该语句将自定义监听器与上传组件结合了起来。

完整代码如下（struts-2.3.8）：

/* 

 * $Id: JakartaMultiPartRequest.java 1384107 2012-09-12 20:14:23Z lukaszlenart $ 

 * Licensed to the Apache Software Foundation (ASF) under one 

 * or more contributor license agreements. See the NOTICE file 

 * distributed with this work for additional information 

 * regarding copyright ownership. The ASF licenses this file 

 * to you under the Apache License, Version 2.0 (the 

 * "License"); you may not use this file except in compliance 

 * with the License. You may obtain a copy of the License at 

 * http://www.apache.org/licenses/LICENSE-2.0 

 * Unless required by applicable law or agreed to in writing, 

 * software distributed under the License is distributed on an 

 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 

 * KIND, either express or implied. See the License for the 

 * specific language governing permissions and limitations 

 * under the License. 

package com.clzhang.struts2.demo12; 

import com.opensymphony.xwork2.LocaleProvider; 

import com.opensymphony.xwork2.inject.Inject; 

import com.opensymphony.xwork2.util.LocalizedTextUtil; 

import com.opensymphony.xwork2.util.logging.Logger; 

import com.opensymphony.xwork2.util.logging.LoggerFactory; 

import org.apache.commons.fileupload.FileItem; 

import org.apache.commons.fileupload.FileUploadBase; 

import org.apache.commons.fileupload.FileUploadException; 

import org.apache.commons.fileupload.RequestContext; 

import org.apache.commons.fileupload.disk.DiskFileItem; 

import org.apache.commons.fileupload.disk.DiskFileItemFactory; 

import org.apache.commons.fileupload.servlet.ServletFileUpload; 

import org.apache.struts2.StrutsConstants; 

import javax.servlet.http.HttpServletRequest; 

import java.io.File; 

import java.io.IOException; 

import java.io.InputStream; 

import java.io.UnsupportedEncodingException; 

import java.util.ArrayList; 

import java.util.Collections; 

import java.util.Enumeration; 

import java.util.HashMap; 

import java.util.List; 

import java.util.Locale; 

import java.util.Map; 

import java.util.Set; 

import org.apache.struts2.dispatcher.multipart.MultiPartRequest; 

 * Multipart form data request adapter for Jakarta Commons Fileupload package. 

public class MyJakartaMultiPartRequest implements MultiPartRequest { 

 static final Logger LOG = LoggerFactory.getLogger(MyJakartaMultiPartRequest.class); 

 // maps parameter name - List of FileItem objects 

 protected Map String, List FileItem files = new HashMap String, List FileItem (); 

 // maps parameter name - List of param values 

 protected Map String, List String params = new HashMap String, List String (); 

 // any errors while processing this request 

 protected List String errors = new ArrayList String (); 

 protected long maxSize; 

 private Locale defaultLocale = Locale.ENGLISH; 

 @Inject(StrutsConstants.STRUTS_MULTIPART_MAXSIZE) 

 public void setMaxSize(String maxSize) { 

 this.maxSize = Long.parseLong(maxSize); 

 @Inject 

 public void setLocaleProvider(LocaleProvider provider) { 

 defaultLocale = provider.getLocale(); 

 /** 

 * Creates a new request wrapper to handle multi-part data using methods adapted from Jason Pells 

 * multipart classes (see class description). 

 * @param saveDir the directory to save off the file 

 * @param request the request containing the multipart 

 * @throws java.io.IOException is thrown if encoding fails. 

 public void parse(HttpServletRequest request, String saveDir) throws IOException { 

 try { 

 setLocale(request); 

 processUpload(request, saveDir); 

 } catch (FileUploadBase.SizeLimitExceededException e) { 

 if (LOG.isWarnEnabled()) { 

 LOG.warn("Request exceeded size limit!", e); 

 String errorMessage = buildErrorMessage(e, new Object[]{e.getPermittedSize(), e.getActualSize()}); 

 if (!errors.contains(errorMessage)) { 

 errors.add(errorMessage); 

 } catch (Exception e) { 

 if (LOG.isWarnEnabled()) { 

 LOG.warn("Unable to parse request", e); 

 String errorMessage = buildErrorMessage(e, new Object[]{}); 

 if (!errors.contains(errorMessage)) { 

 errors.add(errorMessage); 

 protected void setLocale(HttpServletRequest request) { 

 if (defaultLocale == null) { 

 defaultLocale = request.getLocale(); 

 protected String buildErrorMessage(Throwable e, Object[] args) { 

 String errorKey = "struts.messages.upload.error." + e.getClass().getSimpleName(); 

 if (LOG.isDebugEnabled()) { 

 LOG.debug("Preparing error message for key: [#0]", errorKey); 

 return LocalizedTextUtil.findText(this.getClass(), errorKey, defaultLocale, e.getMessage(), args); 

 private void processUpload(HttpServletRequest request, String saveDir) throws FileUploadException, UnsupportedEncodingException { 

 for (FileItem item : parseRequest(request, saveDir)) { 

 if (LOG.isDebugEnabled()) { 

 LOG.debug("Found item " + item.getFieldName()); 

 if (item.isFormField()) { 

 processNormalFormField(item, request.getCharacterEncoding()); 

 } else { 

 processFileField(item); 

 private void processFileField(FileItem item) { 

 if (LOG.isDebugEnabled()) { 

 LOG.debug("Item is a file upload"); 

 // Skip file uploads that dont have a file name - meaning that no file was selected. 

 if (item.getName() == null || item.getName().trim().length() 1) { 

 LOG.debug("No file has been uploaded for the field: " + item.getFieldName()); 

 return; 

 List FileItem values; 

 if (files.get(item.getFieldName()) != null) { 

 values = files.get(item.getFieldName()); 

 } else { 

 values = new ArrayList FileItem (); 

 values.add(item); 

 files.put(item.getFieldName(), values); 

 private void processNormalFormField(FileItem item, String charset) throws UnsupportedEncodingException { 

 if (LOG.isDebugEnabled()) { 

 LOG.debug("Item is a normal form field"); 

 List String values; 

 if (params.get(item.getFieldName()) != null) { 

 values = params.get(item.getFieldName()); 

 } else { 

 values = new ArrayList String (); 

 // note: see http://jira.opensymphony.com/browse/WW-633 

 // basically, in some cases the charset may be null, so 

 // were just going to try to "other" method (no idea if this 

 // will work) 

 if (charset != null) { 

 values.add(item.getString(charset)); 

 } else { 

 values.add(item.getString()); 

 params.put(item.getFieldName(), values); 

 item.delete(); 

 private List FileItem parseRequest(HttpServletRequest servletRequest, String saveDir) throws FileUploadException { 

 DiskFileItemFactory fac = createDiskFileItemFactory(saveDir); 

 ServletFileUpload upload = new ServletFileUpload(fac); 

 upload.setProgressListener(new FileUploadListener(servletRequest));// 设置上传进度的监听 

 upload.setSizeMax(maxSize); 

 return upload.parseRequest(createRequestContext(servletRequest)); 

 private DiskFileItemFactory createDiskFileItemFactory(String saveDir) { 

 DiskFileItemFactory fac = new DiskFileItemFactory(); 

 // Make sure that the data is written to file 

 fac.setSizeThreshold(0); 

 if (saveDir != null) { 

 fac.setRepository(new File(saveDir)); 

 return fac; 

 /* (non-Javadoc) 

 * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getFileParameterNames() 

 public Enumeration String getFileParameterNames() { 

 return Collections.enumeration(files.keySet()); 

 /* (non-Javadoc) 

 * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getContentType(java.lang.String) 

 public String[] getContentType(String fieldName) { 

 List FileItem items = files.get(fieldName); 

 if (items == null) { 

 return null; 

 List String contentTypes = new ArrayList String (items.size()); 

 for (FileItem fileItem : items) { 

 contentTypes.add(fileItem.getContentType()); 

 return contentTypes.toArray(new String[contentTypes.size()]); 

 /* (non-Javadoc) 

 * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getFile(java.lang.String) 

 public File[] getFile(String fieldName) { 

 List FileItem items = files.get(fieldName); 

 if (items == null) { 

 return null; 

 List File fileList = new ArrayList File (items.size()); 

 for (FileItem fileItem : items) { 

 File storeLocation = ((DiskFileItem) fileItem).getStoreLocation(); 

 if (fileItem.isInMemory() storeLocation != null !storeLocation.exists()) { 

 try { 

 storeLocation.createNewFile(); 

 } catch (IOException e) { 

 if (LOG.isErrorEnabled()) { 

 LOG.error("Cannot write uploaded empty file to disk: " + storeLocation.getAbsolutePath(), e); 

 fileList.add(storeLocation); 

 return fileList.toArray(new File[fileList.size()]); 

 /* (non-Javadoc) 

 * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getFileNames(java.lang.String) 

 public String[] getFileNames(String fieldName) { 

 List FileItem items = files.get(fieldName); 

 if (items == null) { 

 return null; 

 List String fileNames = new ArrayList String (items.size()); 

 for (FileItem fileItem : items) { 

 fileNames.add(getCanonicalName(fileItem.getName())); 

 return fileNames.toArray(new String[fileNames.size()]); 

 /* (non-Javadoc) 

 * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getFilesystemName(java.lang.String) 

 public String[] getFilesystemName(String fieldName) { 

 List FileItem items = files.get(fieldName); 

 if (items == null) { 

 return null; 

 List String fileNames = new ArrayList String (items.size()); 

 for (FileItem fileItem : items) { 

 fileNames.add(((DiskFileItem) fileItem).getStoreLocation().getName()); 

 return fileNames.toArray(new String[fileNames.size()]); 

 /* (non-Javadoc) 

 * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getParameter(java.lang.String) 

 public String getParameter(String name) { 

 List String v = params.get(name); 

 if (v != null v.size() 0) { 

 return v.get(0); 

 return null; 

 /* (non-Javadoc) 

 * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getParameterNames() 

 public Enumeration String getParameterNames() { 

 return Collections.enumeration(params.keySet()); 

 /* (non-Javadoc) 

 * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getParameterValues(java.lang.String) 

 public String[] getParameterValues(String name) { 

 List String v = params.get(name); 

 if (v != null v.size() 0) { 

 return v.toArray(new String[v.size()]); 

 return null; 

 /* (non-Javadoc) 

 * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getErrors() 

 public List String getErrors() { 

 return errors; 

 /** 

 * Returns the canonical name of the given file. 

 * @param filename the given file 

 * @return the canonical name of the given file 

 private String getCanonicalName(String filename) { 

 int forwardSlash = filename.lastIndexOf("/"); 

 int backwardSlash = filename.lastIndexOf("//"); 

 if (forwardSlash != -1 forwardSlash backwardSlash) { 

 filename = filename.substring(forwardSlash + 1, filename.length()); 

 } else if (backwardSlash != -1 backwardSlash = forwardSlash) { 

 filename = filename.substring(backwardSlash + 1, filename.length()); 

 return filename; 

 /** 

 * Creates a RequestContext needed by Jakarta Commons Upload. 

 * @param req the request. 

 * @return a new request context. 

 private RequestContext createRequestContext(final HttpServletRequest req) { 

 return new RequestContext() { 

 public String getCharacterEncoding() { 

 return req.getCharacterEncoding(); 

 public String getContentType() { 

 return req.getContentType(); 

 public int getContentLength() { 

 return req.getContentLength(); 

 public InputStream getInputStream() throws IOException { 

 InputStream in = req.getInputStream(); 

 if (in == null) { 

 throw new IOException("Missing content in the request"); 

 return req.getInputStream(); 

 /* (non-Javadoc) 

 * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#cleanUp() 

 public void cleanUp() { 

 Set String names = files.keySet(); 

 for (String name : names) { 

 List FileItem items = files.get(name); 

 for (FileItem item : items) { 

 if (LOG.isDebugEnabled()) { 

 String msg = LocalizedTextUtil.findText(this.getClass(), "struts.messages.removing.file", 

 Locale.ENGLISH, "no.message.found", new Object[]{name, item}); 

 LOG.debug(msg); 

 if (!item.isInMemory()) { 

 item.delete(); 

}

5.2 替换Struts2默认的上传关联类（修改struts.xml）

 !--demo12，struts2文件上传与下载-- constant name="struts.multipart.handler" value="MyJakartaMultiPartRequestRef" / !--demo12，struts2文件上传与下载-- bean type="org.apache.struts2.dispatcher.multipart.MultiPartRequest" name="MyJakartaMultiPartRequestRef" scope="default"/ 

至此，上传文件时将触发我们上面写的FileUploadListener类，捕捉到相关上传进度信息。

6. 修改struts.xml，加入Action配置

 action name="uploadT2" 

 result /struts2/demo12/showResult2.jsp /result 

 /action 

 action name="getState" /action 

第一个Action为提交上传文件表单时用的；第二个Action为轮询上传进度信息用的。

7. 设置上传文件相关参数（struts.properties）

同前一篇文章。

struts.multipart.maxSize=2048000000 

struts.multipart.saveDir=/upload

8. 测试

打开IE，输入地址：http://127.0.0.1:8080/st/struts2/demo12/uploadTest3.jsp

结果如下：

选择几个较大的文件，提交：

最终结果：

7983.html

cgojavaxml