commons-fileupload servlet 多文件上传
需要引入的 jar 包。
commons-fileupload-1.3.2.jar
commons-io-2.2.jar
工程路劲：查看源码
JSP 页面：
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>批量上传</title>
</head>
<body>
<form name="uploadForm" method="post" action="UoloadServlet" enctype="multipart/form-data">
<table border="1">
<thead>
<tr>
<th>名称</th>
<th>文件</th>
</tr>
</thead>
<tbody>
<c:forEach begin="1" end="10" var="i">
<tr>
<td>文件${i}</td>
<td><input type="file" name="file"></td>
</tr>
</c:forEach>
</tbody>
</table>
<input type="submit" name="submit" value="开始上传">
</form>
</body>
</html>servlet 页面
package com.servlet;
import java.io.File;
import java.io.IOException;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.util.FileUtil;
/**
* Servlet implementation class uoloadServlet
*/
public class UoloadServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public UoloadServlet() {
super();
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
* response)
*/
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
doPost(request, response);
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
* response)
*/
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
// 文件上传的路径，这里设置的是服务器项目根路径下的 IMG 目录
String filePath = request.getSession().getServletContext().getRealPath("/")+ "IMG/";
// 获取照片上传工具类，并且批量上传照片文件
List<File> files = FileUtil.getInstance(filePath).upload(request);
// 将上传成功照片的照片传值到页面
request.setAttribute("files", files);
request.getRequestDispatcher("list.jsp").forward(request, response);
}
}
FileUtil.java
package com.util;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
public class FileUtil {
// 文件上传路径
private static String UPLOAD_PATH = null;
/**
* @author Duke 静态内部类，实例化工具类
*/
private static class LazyHolder {
private static final FileUtil FILEUTIL = new FileUtil();
}
/**
* 私有构造函数
*/
private FileUtil() {
}
/**
* 获取工具类实例
*
* @return FileUploadUtil 实例
*/
public static FileUtil getInstance(String uploadPath) {
UPLOAD_PATH = uploadPath;
return LazyHolder.FILEUTIL;
}
/**
* 文件批量上传
*
* @param request
* @param uploadPath
*
*/
public List<File> upload(HttpServletRequest request) {
// 用于存放上传成功的照片
List<File> files = new ArrayList<File>();
try {
FileItemFactory factory = new DiskFileItemFactory();
ServletFileUpload upload = new ServletFileUpload(factory);
List<FileItem> items = upload.parseRequest(request);
for (FileItem fileItem : items) {
// 获得文件名，包括文件路径
String fileFullName = fileItem.getName();
if (fileFullName != null && fileFullName != "" && fileItem.getSize() > 0) {
// 获取文件路径
String fileName = new File(fileFullName).getName();
// 创建文件
File savedFile = new File(UPLOAD_PATH, fileName);
// 如果文件所在文件夹不存在的话，新建文件夹
if (!savedFile.getParentFile().exists()) {
savedFile.getParentFile().mkdirs();
}
// 写入文件
fileItem.write(savedFile);
files.add(savedFile);
}
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return files;
}
/**
* 文件下载
*
* @param filePath
* @throws IOException
* @throws Exception
*/
public void downLoadFile(String filePath, HttpServletResponse response) throws IOException {
// 处理中文乱码问题
filePath = new String(filePath.getBytes("ISO-8859-1"), "UTF-8");
downLoadFile(new File(filePath), response);
}
/**
* 文件下载
*
* @param file
* @throws IOException
*/
public void downLoadFile(File file, HttpServletResponse response) throws IOException {
if (file.exists()) {
response.reset();
response.setContentType("application/x-download");
response.addHeader("Content-Disposition", "attachment; filename="" + URLEncoder.encode(file.getName(), "UTF-8"));
// 输出文件字节流
writeBufferByte(file, response);
}
}
/**
* 输出照片字节流
*
* @throws IOException
*/
public void outputImgByte(String filePath, HttpServletResponse response) throws IOException {
// 处理中文乱码问题
filePath = new String(filePath.getBytes("ISO-8859-1"), "UTF-8");
outputImgByte(new File(filePath), response);
}
/**
* 输出照片字节流
*
* @throws IOException
*/
public void outputImgByte(File file, HttpServletResponse response) throws IOException {
// 文件存在的情况下输出文件
if (file.exists()) {
// 设置相应信息的类型
response.setContentType("image/jpeg");
// 输出文件字节流
writeBufferByte(file, response);
}
}
/**
* 输出文件字节流
*
* @param file
* @param response
* @throws IOException
*/
private void writeBufferByte(File file, HttpServletResponse response) throws IOException {
// 一次读 2048 个字节
byte[] buffer = new byte[2048];
// 获取照片流
FileInputStream fos = new FileInputStream(file);
int count;
while ((count = fos.read(buffer)) > 0) {
// 输出照片流
response.getOutputStream().write(buffer, 0, count);
}
fos.close();
}
}