用commons FileUpload实现文件上传
1、到www.apache.org下载相关jar文件
2、创建一个web project,将相关包引入
（1）web.xml文件配置
(2)index.jsp文件
（3）UploadFileServlet 类的实现
2、创建一个web project,将相关包引入
（1）web.xml文件配置
<?xml version="1.0" encoding="UTF-8"?> <web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> <servlet> <servlet-name>UploadFileServlet</servlet-name> <servlet-class>com.fileupload.servlet.UploadFileServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>UploadFileServlet</servlet-name> <url-pattern>/UploadFileServlet/*</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> </web-app>
(2)index.jsp文件
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme() + "://"
+ request.getServerName() + ":" + request.getServerPort()
+ path + "/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'index.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
<script type="text/javascript">
function getUpFiles(){
var desc = document.getElementById("desc").value;
alert(desc);
}
</script>
</head>
<body>
<%
String fileName = "";
if(request.getAttribute("fileName")!=null){
fileName = (String)request.getAttribute("fileName");
out.println(fileName+"上传成功！");
}
%>
<form method="post" action="UploadFileServlet" name="upForm"
enctype="multipart/form-data" onsubmit="return getUpFiles();">
<table width="100%" border="0">
<tbody>
<tr>
<td width="15%">
文件路径：
</td>
<td width="85%">
<input type="file" name="upFile" size="30px"/>
</td>
</tr>
<tr>
<td width="15%">
文件描述：
</td>
<td width="85%">
<textarea name="desc" rows="10" cols="50"></textarea>
</td>
</tr>
<tr>
<td>
</td>
<td>
<input type="Submit" name="upBotton" value="上传"/>
</td>
</tr>
<tr>
<td>
</td>
<td>
</td>
</tr>
</tbody>
</table>
</form>
</body>
</html>
（3）UploadFileServlet 类的实现
package com.fileupload.servlet;
import java.io.File;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
public class UploadFileServlet extends HttpServlet {
private static final long serialVersionUID = 56890894234786L;
String saveFolder = "falshFolder";
String saveTempFolder = "falshTempFolder";
@SuppressWarnings("unchecked")
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
request.setCharacterEncoding("UTF-8");
// 文件上傳部分
boolean isMultipart = ServletFileUpload.isMultipartContent(request);
if (isMultipart == true) {
try {
// 实例化一个硬盘文件工厂,用来配置上传组件ServletFileUpload
DiskFileItemFactory factory = new DiskFileItemFactory();
// 设置上传文件时用于临时存放文件的内存大小,这里是4K.多于的部分将临时存在硬盘
factory.setSizeThreshold(4096);
//设置存放临时文件的目录,web根目录下的ImagesUploadTemp目录
factory.setRepository(new File(request.getRealPath("/")+
saveTempFolder));
// 用配置好的工厂实例化上传组件
ServletFileUpload upload = new ServletFileUpload(factory);
// 得到所有的表单域，它们目前都被当作FileItem
List<FileItem> fileItems = upload.parseRequest(request);
Iterator<FileItem> iter = fileItems.iterator();
// 依次处理每个表单域
while (iter.hasNext()) {
FileItem item = (FileItem) iter.next();
if(item.isFormField()){
// 如果item是正常的表单域
String name = item.getFieldName();
String value = item.getString();
System.out.print("表单域名为:"+name+"表单域值为:"+value);
}
else{
// 如果item是文件上传表单域
// 获得文件名及路径
String fileName = item.getName();
if (fileName != null) {
//获取要上传的文件
File fullFile = new File(item.getName());
String t_ext = fullFile.getName().substring(fullFile.getName().lastIndexOf(".") + 1);
// 如果文件存在则上传
if(fullFile.exists()){
//存放文件的路径
String filePath = request.getRealPath("/") + saveFolder;
long now = System.currentTimeMillis();
// 根据系统时间生成上传后保存的文件名
String name = String.valueOf(now);
File fileOnServer = new File(filePath,
name+"."+t_ext);
item.write(fileOnServer);
System.out.println("文件"+fileOnServer.getName()+"上传成功");
request.setAttribute("fileName", fullFile.getName());
}
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
} else {
System.out.println("the enctype must be multipart/form-data");
}
// 返回原页
RequestDispatcher dispatcher = request
.getRequestDispatcher("index.jsp");
dispatcher.forward(request, response);
return;
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
doPost(request, response);
}
}