版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/u012829611/article/details/70056229
一、Demo介绍
基于struts2框架，实现多文件的上传和下载功能。
实现原理图：
部分界面图：
上传成功及下载页面：
二、主要代码
uploadFile.jsp:在form表单中包含一个文本框（上传用户的姓名）和两个文件上传选项.
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<!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=UTF-8">
<title>多文件上传</title>
</head>
<body>
<center>
<s:form action="docUpload" method="post" enctype="multipart/form-data">
<s:textfield name="name" label="姓名" size="20"/>
<s:file name="upload" label="选择文档" size="20"/>
<s:file name="upload" label="选择文档" size="20"/>
<s:submit value="确认上传" align="center"/>
</s:form>
</center>
</body>
</html>struts.xml:分别配置了上传和下载的Action（DocUploadAction和DocDownloadAction）。在文件上传时，做了一些简单的过滤。
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.1.7//EN"
"http://struts.apache.org/dtds/struts-2.1.7.dtd">
<struts>
<constant name="struts.i18n.encoding" value="utf-8"/>
<package name="default" extends="struts-default">
<action name="docUpload" class="com.cy.action.DocUploadAction">
<!-- 使用fileUpload拦截器 -->
<interceptor-ref name="fileUpload">
<!-- 指定允许上传的文件大小最大为50000字节 -->
<param name="maximumSize">50000</param>
</interceptor-ref>
<!-- 配置默认系统拦截器栈 -->
<interceptor-ref name="defaultStack"/>
<!-- param子元素配置了DocUploadAction类中savePath属性值为/upload -->
<param name="savePath">/upload</param>
<result>/showFile.jsp</result>
<!-- 指定input逻辑视图，即不符合上传要求，被fileUpload拦截器拦截后，返回的视图页面 -->
<result name="input">/uploadFile.jsp</result>
</action>
<action name="docDownload" class="com.cy.action.DocDownloadAction">
<!-- 指定结果类型为stream -->
<result type="stream">
<!-- 指定下载文件的文件类型 text/plain表示纯文本 -->
<param name="contentType">
application/msword,text/plain
</param>
<!-- 指定下载文件的入口输入流 -->
<param name="inputName">inputStream</param>
<!-- 指定下载文件的处理方式与文件保存名 attachment表示以附件形式下载，也可以用inline表示内联即在浏览器中直接显示，默认值为inline -->
<param name="contentDisposition">
attachment;filename="${downloadFileName}"
</param>
<!-- 指定下载文件的缓冲区大小，默认为1024 -->
<param name="bufferSize">40960</param>
</result>
</action>
</package>
</struts>DocUploadAction.java：采用数组方式实现多文件上传。
package com.cy.action;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Date;
import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionSupport;
public class DocUploadAction extends ActionSupport {
private String name;
private File[] upload;
private String[] uploadContentType;
private String[] uploadFileName;
private String savePath;
private Date createTime;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public File[] getUpload() {
return upload;
}
public void setUpload(File[] upload) {
this.upload = upload;
}
public String[] getUploadContentType() {
return uploadContentType;
}
public void setUploadContentType(String[] uploadContentType) {
this.uploadContentType = uploadContentType;
}
public String[] getUploadFileName() {
return uploadFileName;
}
public void setUploadFileName(String[] uploadFileName) {
this.uploadFileName = uploadFileName;
}
public String getSavePath() {
return savePath;
}
public void setSavePath(String savePath) {
this.savePath = savePath;
}
public Date getCreateTime(){
createTime=new Date();
return createTime;
}
public static void copy(File source,File target){
InputStream inputStream=null;
OutputStream outputStream=null;
try{
inputStream=new BufferedInputStream(new FileInputStream(source));
outputStream=new BufferedOutputStream(new FileOutputStream(target));
byte[] buffer=new byte[1024];
int length=0;
while((length=inputStream.read(buffer))>0){
outputStream.write(buffer, 0, length);
}
}catch(Exception e){
e.printStackTrace();
}finally{
if(null!=inputStream){
try {
inputStream.close();
} catch (IOException e2) {
e2.printStackTrace();
}
}
if(null!=outputStream){
try{
outputStream.close();
}catch(Exception e2){
e2.printStackTrace();
}
}
}
}
@Override
public String execute() throws Exception {
for(int i=0;i<upload.length;i++){
String path=ServletActionContext.getServletContext().getRealPath(this.getSavePath())+"\\"+this.uploadFileName[i];
File target=new File(path);
copy(this.upload[i],target);
}
return SUCCESS;
}
}showFile.jsp：对上传的文件设置了超链接，供下载使用。
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<!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=UTF-8">
<title>显示上传文档</title>
</head>
<body>
<center>
<font style="font-size:18px;color:red">上传者：<s:property value="name"/></font>
<table width="45%" cellpadding="0" cellspacing="0" border="1">
<tr>
<th>文件名称</th>
<th>上传者</th>
<th>上传时间</th>
</tr>
<s:iterator value="uploadFileName" status="st" var="doc">
<tr>
<td align="center">
<a href="docDownload.action?downPath=upload/<s:property value="#doc"/>">
<s:property value="#doc"/>
</a>
</td>
<td align="center"><s:property value="name"/></td>
<td align="center"><s:date name="createTime" format="yyyy-MM-dd HH:mm:ss"/></td>
</tr>
</s:iterator>
</table>
</center>
</body>
</html>三、注意事项
1、实现文件上传与下载功能，必须在uploadFile.jsp页面中form表单中设置enctype=”multipart/form-data”属性。
2、所有form表单中action=“xxx”属性，其中xxx必须与struts.xml中配置的action的name值完全一致。
3、在form表单中设置属性enctype=”multipart/form-data”的情况下，如何获取表单中提交的文本值？具体实现方法见http://blog.csdn.net/u012829611/article/details/70072569
4、一个struts.xml文件中可以配置多个action，在配置过程中需要与第二点注意事项相结合。
5、这里只列出部分主要代码，如需完整Demo代码，可到http://download.csdn.net/my下载
转载请注明！谢谢！