Struts 2 实现多文件上传

Struts2中支持文件上传与下载的两个JAR文件是：

commons-fileupload-1.2.2.jar

commons-io-1.4.jar，

这两个包要到apache网站上单独下载，下载网址是：

http://commons.apache.org/fileupload/download_fileupload.cgi，

可下载：commons-fileupload-1.2.2-bin.zip，解压后，在它的lib中有commons-fileupload-1.2.2.jar

http://commons.apache.org/io/download_io.cgi，

可下载：commons-io-1.4-bin.zip，解压后，有commons-io-1.4.jar

要上传文件需要用到标签:<s:file>

还要用到表单的“enctype”属性，设置为：enctype="multipart/form-data" ，传送二进制数据文件。

Demo：

1、首页 index.jsp

 1 <%@ page language="java" contentType="text/html;charset=UTF-8"%>
 2 <%@ taglib prefix="s" uri="/struts-tags"%>
 3 <html>
 4     <head>
 5         <title>上传文件</title>
 6     </head>
 7     <body vLink="#006666" link="#003366" bgColor="#E0F0F8">
 8         <br>
 9         <b>上传文件</b>
10         <s:form action="upload" enctype="multipart/form-data" method="post">
11 　　　　　　　<s:file name="upload" label="选择文件1">
12             </s:file>
13             <s:file name="upload" label="选择文件2">
14             </s:file>
15             <s:file name="upload" label="选择文件3">
16             </s:file>
17             <s:submit value="上传"></s:submit>
18 　　　　  </s:form>
19 　　</body>
20 </html>

2、struts.xml

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <!DOCTYPE struts PUBLIC
 3     "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
 4     "http://struts.apache.org/dtds/struts-2.0.dtd">
 5 
 6 <struts>
 7     <constant name="struts.enable.DynamicMethodInvocation" value="false" />
 8     <constant name="struts.devMode" value="true" />
 9 
10     <package name="up-load" extends="struts-default">
11         <action name="upload" class="com.action.UpLoadAction">
12             <!-- 部署本工程前，要在WebRoot下手工创建文件夹upload,上传保存到tomcat容器的webapps中的本工程的upload文件夹中 -->
13             <param name="savePath">upload</param>  
14             <!-- 上传失败时返回的视图页面 -->
15             <result name="success">upsuccess.jsp</result>
16             <result name="input">uperror.jsp</result>
17             <!-- 声明action使用的拦截器 fileUpload -->
18             <interceptor-ref name="fileUpload">
19                  <!-- 限制上传的文件类型 -->
20                 <param name="allowedTypes">image/gif,image/jpeg,image/x-png,image/bmp,text/plain,application/msword,application/vnd.ms-excel,application/x-zip-compressed,application/pdf,application/vnd.ms-powerpoint</param>
21                 <!-- 限制上传文件大小为2048000字节(2M) -->
22                 <param name="maximumSize">2048000</param>   
23             </interceptor-ref>
24             <!-- 配置Struts 2 的默认拦截器栈 -->
25             <interceptor-ref name="defaultStack" />
26         </action>
27     </package>
28 </struts>
29 
30 <!-- 对上传类型的说明： -->
31 <!-- gif文件：image/gif -->
32 <!-- jpg文件：image/jpeg -->
33 <!-- png文件: image/x-png -->
34 <!-- bmp文件：image/bmp -->
35 <!-- txt文件：text/plain -->
36 <!-- doc文件：application/msword -->
37 <!-- xls文件：application/vnd.ms-excel -->
38 <!-- zip、jar文件： application/x-zip-compressed -->
39 <!-- pdf文件：application/pdf -->
40 <!-- ppt文件：application/vnd.ms-powerpoint -->
41 <!-- 除上述类型外的其它文件类型：application/octet-stream -->

3、Action代码

 1 package com.action;
 2 
 3 import java.io.*;
 4 import org.apache.struts2.ServletActionContext;
 5 import com.opensymphony.xwork2.ActionSupport;
 6 
 7 public class UpLoadAction extends ActionSupport {
 8     private File[] upload; // 封装上传文件
 9     private String[] uploadContentType; // 封装上传文件类型
10     private String[] uploadFileName; // 封装上传文件名
11     private String savePath; // 封装上传文件在服务器tomcat容器上的保存路径
12 
13     public File[] getUpload() {
14         return upload;
15     }
16 
17     public void setUpload(File[] upload) {
18         this.upload = upload;
19     }
20 
21     public String[] getUploadContentType() {
22         return uploadContentType;
23     }
24 
25     public void setUploadContentType(String[] uploadContentType) {
26         this.uploadContentType = uploadContentType;
27     }
28 
29     public String[] getUploadFileName() {
30         return uploadFileName;
31     }
32 
33     public void setUploadFileName(String[] uploadFileName) {
34         this.uploadFileName = uploadFileName;
35     }
36 
37     public String getSavePath() {
38         // 以下ServletActionContext.getServletContext().getRealPath("")方法获取本工程在tomcat容器中的真实绝对路径，加上参数savepath，进一步得到下一级savepath所代表的文件夹的绝对路径
39         String realpath = ServletActionContext.getServletContext().getRealPath(savePath); // 应为使用的是2.0的ServletAPI,所以不能调用request.getRealPath()
40         return realpath;
41     }
42 
43     public void setSavePath(String savePath) {
44         this.savePath = savePath;
45     }
46 
47     public String execute() throws Exception {
48         File[] files = getUpload();
49         for (int i = 0; i < files.length; i++) {
50             FileInputStream fileInput = new FileInputStream(files[i]); // 创建文件输入流
51             FileOutputStream fileOutput = new FileOutputStream(getSavePath() + "\\" + getUploadFileName()[i]); // 创建文件输出流
52             byte[] b = new byte[2048]; // 缓冲数组大小2KB
53             int len = 0;
54             while ((len = fileInput.read(b)) > 0) // finout.read(b)实现从输入流读1KB数据到数组b中,返回读取的字节数len，遇到文件尾返回-1
55             {
56                 fileOutput.write(b, 0, len); // 将b中len字节数据写到输出流中
57             }
58             //fileInput.close(); // 关闭输入流
59             //fileOutput.close(); // 关闭输出流
60         }
61         return "success";
62     }
63 }

4、upsuccess.jsp

 1 <%@ page language="java" contentType="text/html;charset=UTF-8" %>
 2 <%@ taglib prefix="s" uri="/struts-tags"%>  
 3 <html>
 4 <head>
 5 <title>上传文件成功</title>
 6 </head>
 7 <body vLink="#006666" link="#003366" bgColor="#E0F0F8">
 8 <img src="img/smile.gif">
 9 <h3>上传文件成功：</h3>
10     <s:property value="uploadFileName"/><br><br>
11 <a href="index.jsp">继续上传</a>
12 <s:debug></s:debug>
13 </body>
14 </html>

4、uperror.jsp

 1 <%@ page contentType="text/html;charset=UTF-8" language="java"%>
 2 <%@ taglib prefix="s" uri="/struts-tags"%>
 3 <html>
 4 <head>
 5 <title>查询失败</title>
 6 </head>
 7 <body vLink="#006666" link="#003366" bgColor="#E0F0F8">
 8 <img src="img/cry.gif">
 9 <h1>上传失败！</h1><br><br>
10 <s:fielderror></s:fielderror>
11 <br><br>
12 <a href="index.jsp">返回上传页面</a>
13 </body>
14 </html>

PS:

若上传后文件名乱码，只需将页面的编码方式和struts.xml的设置的编码方式都用成gbk 即可

Struts.xml的配置文件<constant name="struts.i18n.encoding" value="gbk"></constant>

struts2 jpg文件上传失败 Content-Type not allowed:

原因：ie会把 jpg、jpeg翻译成image/pjpeg，png翻译成image/x-png 。而火狐则很标准：jpg、jpeg翻译成image/jpeg，png翻译成image/png。

解决方法：用火狐、谷歌等浏览器 or

<param name="allowedTypes"> image/bmp,image/png,image/gif,image/jpeg,image/jpg,image/x-png, image/pjpeg </param>