commonfileupload

apache的common-fileupload简单用法实例

1 jsp

 1 <%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%>
 2 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 3 <html>
 4 <head>
 5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
 6 <title>欢迎使用</title>
 7 </head>
 8 
 9 <body>
10     <div>
11         <form action="servlet/FileUploadServlet" method="post" enctype="multipart/form-data">
12             <input type="file" name="file"/>
13             <input type="text" name="desc"/>
14             <input type="submit" name="submit" value="上传"/> 
15         </form>
16     </div>
17 </body>
18 </html>

2、Servlet

 1 package com.test.upload.servlet;
 2 
 3 import java.io.File;
 4 import java.io.IOException;
 5 import java.io.UnsupportedEncodingException;
 6 import java.util.ArrayList;
 7 import java.util.Iterator;
 8 import java.util.List;
 9 
10 import javax.servlet.ServletException;
11 import javax.servlet.http.HttpServlet;
12 import javax.servlet.http.HttpServletRequest;
13 import javax.servlet.http.HttpServletResponse;
14 
15 import org.apache.commons.fileupload.FileItem;
16 import org.apache.commons.fileupload.FileUploadException;
17 import org.apache.commons.fileupload.disk.DiskFileItemFactory;
18 import org.apache.commons.fileupload.servlet.ServletFileUpload;
19 import org.apache.commons.lang.StringUtils;
20 
21 
22 public class FileUploadServlet extends HttpServlet {
23     
24     private static final long serialVersionUID = 6896969016159333196L;
25     private static final int MAX_FILE_SIZE = 10*1024*1024;//10MB
26     public void doGet(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException{
27         doPost(request, response);
28     }
29     
30     public void doPost(HttpServletRequest request,HttpServletResponse response) throws ServletException{
31         try {
32             request.setCharacterEncoding("utf-8");
33         } catch (UnsupportedEncodingException e2) {
34             e2.printStackTrace();
35         }
36         String path= "d:"+File.separator+"temp"+File.separator;
37         File file = new File(path);
38         if(!file.exists()){
39             file.mkdir();
40         }
41         DiskFileItemFactory factory = new DiskFileItemFactory();
42         factory.setSizeThreshold(4096);
43         factory.setRepository(file);
44         
45         ServletFileUpload upload= new ServletFileUpload(factory);
46         upload.setSizeMax(MAX_FILE_SIZE);
47         
48         List items = new ArrayList();
49         try {
50             items = upload.parseRequest(request);
51             Iterator iterable = items.iterator();
52             while(iterable.hasNext()){
53                 FileItem fileItem = (FileItem) iterable.next();
54                 
55                 if(!fileItem.isFormField()){
56                     String tempName = fileItem.getName();
57                     if(!StringUtils.isEmpty(tempName) && fileItem.getSize() > 0){
58                         System.out.println(fileItem.getName()+","+fileItem.getFieldName());
59                         File upFile = new File(path+tempName);
60                         fileItem.write(upFile);
61                     }else {
62                         System.out.println("附件为空");
63                     }
64                 }
65             }
66         } catch (FileUploadException e1) {
67             e1.printStackTrace();
68         } catch (Exception e) {
69             e.printStackTrace();
70         }
71     }
72 }

3 web.xml

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
 3   <display-name>上传文件</display-name>
 4   
 5   <servlet>
 6       <servlet-name>FileUploadServlet</servlet-name>
 7       <servlet-class>com.test.upload.servlet.FileUploadServlet</servlet-class>
 8   </servlet>
 9   <servlet-mapping>
10       <servlet-name>FileUploadServlet</servlet-name>
11       <url-pattern>/servlet/FileUploadServlet</url-pattern>
12   </servlet-mapping>
13   <welcome-file-list>
14     <welcome-file>upload.jsp</welcome-file>
15   </welcome-file-list>
16   
17 </web-app>

增加个用jquery.form.js上传

 1 <%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%>
 2 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 3 <html>
 4 <head>
 5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
 6 <title>欢迎使用</title>
 7 </head>
 8 <script type="text/javascript" src="js/jquery.js"></script>
 9 <script type="text/javascript" src="js/jquery.form.js"></script>
10 <script type="text/javascript">
11     function submitform(){
12         var options = {
13                 url:'servlet/FileUploadServlet',
14                 dataType:"json",
15                 type:'post',
16                 success: function(){
17                     $('#output1').html("提交成功！").show(); 
18                 }
19         };
20         $("#form1").ajaxSubmit(options);
21         return false;
22         }
23     
24 
25 </script>
26 <body>
27     <div>
28         <form id="form1" action="servlet/FileUploadServlet" method="post" enctype="multipart/form-data" >
29             <input type="file" name="file"/>
30             <input type="text" name="desc"/>
31             <button type="button" name="btn1" onclick="javascript:submitform();">上传</button>
32         </form>
33     </div>
34     <div id="output1">
35     </div>
36 </body>
37 </html>

jquery form中options参数详见：http://www.malsup.com/jquery/form/#options-object

有关文件上传的有个知识点:enctype

1 application/x-www-form-urlencoded (默认值)
2 multipart/form-data
3 text/plain

有关enctype详细见：http://wenku.baidu.com/view/7d2be4ea81c758f5f61f67fa.html