上传文件

 1 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 2 <html>
 3 <head>
 4 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 5 <title>upload.html</title>
 6 </head>
 7 <body>
 8     <form method="POST"  enctype="multipart/form-data"  action="upload">
 9         username : <input type="text" name="username" size=45 /> <br/>
10         file1 : <input type="file" name="file1" size=45/><br/>
11         file2 : <input type="file" name="file2" size=45/><br/>
12         <input type="submit" name="submit" value="upload" />
13     </form>
14 </body>
15 </html>

upload.html

 1
　　//UploadServlet.java，用于接收处理表单内容
 package com.demo;
 2 
 3 import java.io.File;
 4 import java.io.IOException;
 5 import java.io.PrintWriter;
 6 import java.util.Iterator;
 7 import java.util.List;
 8 
 9 import javax.servlet.ServletException;
10 import javax.servlet.http.HttpServlet;
11 import javax.servlet.http.HttpServletRequest;
12 import javax.servlet.http.HttpServletResponse;
13 
14 import org.apache.commons.fileupload.FileItem;
15 import org.apache.commons.fileupload.FileUploadException;
16 import org.apache.commons.fileupload.disk.DiskFileItemFactory;
17 import org.apache.commons.fileupload.servlet.ServletFileUpload;
18 
19 
20 public class UploadServlet extends HttpServlet{
21     @Override
22     protected void doGet(HttpServletRequest req, HttpServletResponse resp)
23             throws ServletException, IOException {
24         doPost(req, resp);
25     }
26     @Override
27     protected void doPost(HttpServletRequest req, HttpServletResponse resp)
28             throws ServletException, IOException {
29         //1- 设置MIME类型，获取输出流
30         resp.setContentType("text/html;charset=utf-8");
31         PrintWriter out = resp.getWriter();
32         
33         //2- 加载镜像文件工厂
34         DiskFileItemFactory factory = new DiskFileItemFactory();
35         //2-1 设置缓冲区大小
36         factory.setSizeThreshold(2*1024);
37         //2-2 设置文件临时存放目录
38         factory.setRepository(new File("D:\temp"));
39         
40         //3- 加载servletFileUpload方法，获取文件列表
41         ServletFileUpload upload = new ServletFileUpload(factory);
42         try {
43             List<FileItem> items = upload.parseRequest(req);
44             Iterator its = items.iterator();
45             while (its.hasNext()) {
46 
47                 FileItem item = (FileItem) its.next();
48                 if (item.isFormField()) {
49                     handleFormField(item,out);
50                 }else {
51                     handleUploadField(item,out);
52                 }
53                 
54             }
55         } catch (FileUploadException e) {
56             e.printStackTrace();
57         }finally {
58             out.close();
59         }
60     }
61     //处理上传域的方法
62     private void handleUploadField(FileItem item, PrintWriter out) {
63         //1- 获取文件名
64         String fname = item.getName();
65         //2- 判断文件名中是否含有文件路径
66         int index = -1;
67         if ((index = fname.lastIndexOf("\")) != -1) {
68             //若存在，则截取文件名
69             fname = fname.substring(index +1);
70         }
71         //3- 判断文件是否已经上传
72         long size = fname.length();
73         if ("".equals(fname) && size==0) {//未上传，则什么都不做
74             return;
75         }
76         //上传了文件，则保存到本地磁盘中
77         File dest = new File("d:\store\"+fname);
78         try {
79             item.write(dest);
80         //4- 通知客户端，保存成功
81             out.print(fname +"  保存成功！"+"<br />");
82         } catch (Exception e) {
83             e.printStackTrace();
84         }
85         
86         
87     }
88     //处理表单控件域的方法
89     private void handleFormField(FileItem item, PrintWriter out) {
90         //1- 获取表单控件的name属性名称
91         String name = item.getName();
92         //2- 获得表单控件的value属性值
93         String value = item.getString();
94         out.println("---------------表单控件信息----------------");
95         out.println(name + " = " +value );
96         
97         
98     }
99 }

1 
　　//web.xml中的配置
<servlet>
2       <servlet-name>upload</servlet-name>
3       <servlet-class>com.demo.UploadServlet</servlet-class>
4   </servlet>
5   <servlet-mapping>
6     <servlet-name>upload</servlet-name>
7       <url-pattern>/upload</url-pattern>
8   </servlet-mapping>

附件：所需要的lib包

commons-fileupload-1.2.1.jar
commons-io-1.4.jar