struts2:上传多个文件时实现带进度条、进度详细信息的示范
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。
目录
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。
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
<%@ 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"> <tr> <td width="176"> <div align="center"> 用户账号 </div> </td> <td width="626"> <input type="text" name="fileUploadTools.username" /> </td> </tr> <tr> <td> <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" style="width:500"></div> <br/> <div id="progressDetail" class="demo-description"> <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。
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
<%@ 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。
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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。
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
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):
![](https://images.cnblogs.com/OutliningIndicators/ContractedBlock.gif)
/* * $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 Pell's * 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 don't 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 // we're 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" class="com.clzhang.struts2.demo12.MyJakartaMultiPartRequest" 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" class="com.clzhang.struts2.demo12.UploadTest2Action"> <result>/struts2/demo12/showResult2.jsp</result> </action> <action name="getState" class="com.clzhang.struts2.demo12.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: