commons fileupload 相关的代码

〔转〕commons-fileupload组件实现多文件上传

这几天在网上看看，关于commons－fileupload组件的使用介绍太乱了，把他们的代码用用，编译起来错误态度，所以我今天把jsp+commons-fileupload多文件上传搞定了，整理出来，供大家分享，学习。前些天做好了JSP+Smart-upload多文件上传，查了些网上的资料，说是Smart-upload文件上传在传输大文件的时候，浏览器会崩溃，故转向Commons-FileUpload,在查阅资料，又在自己电脑上配置后成功，下面具体说说:

在开始之前你要准备以下几个东西:
1. commons-FileUpload 1.2 包 
下载地址:http://jakarta.apache.org/commons/fileupload/
2. commons-IO 1.3.1 包 
下载地址:http://jakarta.apache.org/commons/io/
3. Commons-BeanUtils 1.7 包 
下载地址:http://jakarta.apache.org/commons/beanutils/

在你的webapp目录下,有一个文件名称是：upload.html，三个文件夹名称是：ImagesUploaded,ImagesUploadTemp,WEB-INF.

在你的webapp目录下，WEN-INF下，lib目录下有如下jar文件：

commons-beanutils.jar, commons-beanutils-bean-collections.jar, commons-beanutils-core.jar, commons-fileupload-1.2.jar, commons-io-1.3.2.jar.

在你的webapp目录下，WEN-INF下，classes目录下有如下java文件：FileUploadServlet.java。

编译成class文件。下面有详细代码。

把下载来的上面三个压缩文件下的java文件，拷贝到classes文件下，构成org包，其中org下目录如下：org→apache →commons→下有四个文件夹：beanutils,collections,fileupload,io.

代码清单：

upload.html:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">

 

<html>

       <head>

       <meta http-equiv="Content-Type" content="text/html;charset=utf-8">

              <title>Untitled</title>

       </head>

 

       <body>

              <form action="FileUploadServlet" method="post" enctype="multipart/form-data">

                     <input type="file" size="30" name="test1" /><br />

            <input type="file" size="30" name="test2" /><br />

                     <br />

                     <input name="up" type="submit" value="上传" />

              </form>

       </body>

</html>

FileUploadServlet.java

import java.io.File;

import java.io.IOException;

import java.io.PrintWriter;

import java.util.Iterator;

import java.util.List;

 

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.FileUploadException;

import org.apache.commons.fileupload.FileUploadBase.SizeLimitExceededException;

import org.apache.commons.fileupload.disk.DiskFileItemFactory;

import org.apache.commons.fileupload.servlet.ServletFileUpload;

 

public class FileUploadServlet extends HttpServlet {

 

 public FileUploadServlet() {

  super();

 }

 

 public void destroy() {

  super.destroy(); // Just puts "destroy" string in log

  // Put your code here

 }

 

 public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

  doPost(request, response);

 }

 

 public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

 

  final long MAX_SIZE = 10 * 1024 * 1024;// 设置上传文件最大为 10M

 

  // 允许上传的文件格式的列表

  final String[] allowedExt = new String[] { "jpg", "JPG","jpeg","JPEG", "gif", "GIF","txt","TXT","doc","DOC", "docx","DOCX", "mp3","MP3", "wma","WMA", "m4a","M4A","zip","ZIP","rar","RAR" };

  response.setContentType("text/html");

 

  // 设置字符编码为UTF-8, 这样支持汉字显示

  response.setCharacterEncoding("UTF-8");

 

  // 实例化一个硬盘文件工厂,用来配置上传组件ServletFileUpload

  DiskFileItemFactory dfif = new DiskFileItemFactory();

  dfif.setSizeThreshold(16384);// 设置上传文件时用于临时存放文件的内存大小,这里是16K.多于的部分将临时存在硬盘

  dfif.setRepository(new File(request.getRealPath("/") + "ImagesUploadTemp"));// 设置存放临时文件的目录,web根目录下的ImagesUploadTemp目录

 

  // 用以上工厂实例化上传组件

  ServletFileUpload sfu = new ServletFileUpload(dfif);

  // 设置最大上传尺寸

  sfu.setSizeMax(MAX_SIZE);

 

  PrintWriter out = response.getWriter();

  // 从request得到所有上传域的列表

  List fileList = null;

  try {

   fileList = sfu.parseRequest(request);

  } catch (FileUploadException e) {// 处理文件尺寸过大异常

   if (e instanceof SizeLimitExceededException) {

    out.println("文件尺寸超过规定大小:" + MAX_SIZE + "字节<p />");

    out.println("<a href=/"upload.html/" target=/"_top/">返回</a>");

    return;

   }

   e.printStackTrace();

  }

  // 没有文件上传

  if (fileList == null || fileList.size() == 0) {

   out.println("请选择上传文件<p />");

   out.println("<a href=/"upload.html/" target=/"_top/">返回</a>");

   return;

  }

  // 得到所有上传的文件

  Iterator fileItr = fileList.iterator();

  // 循环处理所有文件

  while (fileItr.hasNext()) {

   FileItem fileItem = null;

   String path = null;

   long size = 0;

   // 得到当前文件

   fileItem = (FileItem) fileItr.next();

   // 忽略简单form字段而不是上传域的文件域(<input type="text" />等)

   if (fileItem == null || fileItem.isFormField()) {

    continue;

   }

   // 得到文件的完整路径

   path = fileItem.getName();

   // 得到文件的大小

   size = fileItem.getSize();

   if ("".equals(path) || size == 0) {

    out.println("请选择上传文件<p />");

    out.println("<a href=/"upload.html/" target=/"_top/">返回</a>");

    return;

   }

 

   // 得到去除路径的文件名

   String t_name = path.substring(path.lastIndexOf("//") + 1);

   // 得到文件的扩展名(无扩展名时将得到全名)

   String t_ext = t_name.substring(t_name.lastIndexOf(".") + 1);

   // 拒绝接受规定文件格式之外的文件类型

   int allowFlag = 0;

   int allowedExtCount = allowedExt.length;

   for (; allowFlag < allowedExtCount; allowFlag++) {

    if (allowedExt[allowFlag].equals(t_ext))

     break;

   }

   if (allowFlag == allowedExtCount) {

    out.println("请上传以下类型的文件<p />");

    for (allowFlag = 0; allowFlag < allowedExtCount; allowFlag++)

     out.println("*." + allowedExt[allowFlag]

       + "&nbsp;&nbsp;&nbsp;");

    out.println("<p /><a href=/"upload.html/" target=/"_top/">返回</a>");

    return;

   }

 

   long now = System.currentTimeMillis();

   // 根据系统时间生成上传后保存的文件名

   String prefix = String.valueOf(now);

   // 保存的最终文件完整路径,保存在web根目录下的ImagesUploaded目录下

   String u_name = request.getRealPath("/") + "ImagesUploaded/" + prefix + "." + t_ext;

   try {

    // 保存文件

    fileItem.write(new File(u_name));

    out.println("文件上传成功. 已保存为: " + prefix + "." + t_ext + " &nbsp;&nbsp;文件大小: " + size + "字节<p />");

    out.println("<a href=/"upload.html/" target=/"_top/">继续上传</a>");

   } catch (Exception e) {

    e.printStackTrace();

   }

 }

 

 }

 

 public void init() throws ServletException {

  // Put your code here

 }

 

}

在浏览器里输入：http://localhost:8080/你的webapp/upload.html.就可以看到文件上传的页面了。

祝你好运。