记录-spring MultipartFile 文件上传

注意：以下上传和下载方法未必完全正确，不同浏览器效果不同，建议不要使用IE
/**
  * 简单的文件上传
  * @author:qiuchen
  * @createTime:2012-6-19
  * @param request
  * @param response
  * @param errors
  * @return
  * @throws Exception
  */
 @RequestMapping(value = "/upload", method = RequestMethod.POST)
 public ModelAndView onSubmit(HttpServletRequest request,HttpServletResponse response, BindException errors) throws Exception {
  //上传文件处理器
  MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request;
  //文件对象
  CommonsMultipartFile file = (CommonsMultipartFile) multipartRequest.getFile("file");

  //从表单域中获取文件对象的详细,如：文件名称等等
  String name = multipartRequest.getParameter("name");
  System.out.println("name: " + name);

  // 获得文件名(全路径)
  String realFileName = file.getOriginalFilename();
  realFileName = encodeFilename(realFileName,request);
  System.out.println("获得文件名：" + realFileName);
  // 获取当前web服务器项目路径
  String ctxPath = request.getSession().getServletContext().getRealPath("/")+ "fileupload/";

  // 创建文件夹
  File dirPath = new File(ctxPath);
  if (!dirPath.exists()) {
   dirPath.mkdir();
  }
  //创建文件
  File uploadFile = new File(ctxPath + realFileName);

  //Copy文件
  FileCopyUtils.copy(file.getBytes(), uploadFile);

   return new ModelAndView("success");
 }

/**
  * 批量上传文件
  * @author:qiuchen
  * @createTime:2012-6-19
  * @param request
  * @param response
  * @param errors
  * @return
  * @throws Exception
  */
 @RequestMapping(value = "/upload2", method = RequestMethod.POST)
 public ModelAndView onSubmit2(HttpServletRequest request,HttpServletResponse response, BindException errors) throws Exception {
  //文件处理器
  MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request;
  //文件列表
  Map<String, MultipartFile> fileMap = multipartRequest.getFileMap();
  //获取服务器上传文件夹地址
  String ctxPath = request.getSession().getServletContext().getRealPath("/")+ "\\" + "fileupload\\";
  //创建文件夹
  File file = new File(ctxPath);
  if (!file.exists()) {
   file.mkdir();
  }

  String fileName = null;
  for (Map.Entry<String, MultipartFile> entity : fileMap.entrySet()) {
   //单个文件
   MultipartFile mf = entity.getValue();
   //文件名
   fileName = mf.getOriginalFilename();
   //创建文件
   File uploadFile = new File(ctxPath + fileName);
   //copy从内存中复制到磁盘上
   FileCopyUtils.copy(mf.getBytes(), uploadFile);
  }
    return new ModelAndView("success");
 }

/**
     * 设置下载文件中文件的名称
     * @param filename
     * @param request
     * @return
     */
 public static String encodeFilename(String filename,HttpServletRequest request) {
  /**
   * 获取客户端浏览器和操作系统信息 在IE浏览器中得到的是：User-Agent=Mozilla/4.0 (compatible; MSIE
   * 6.0; Windows NT 5.1; SV1; Maxthon; Alexa Toolbar)
   * 在Firefox中得到的是：User-Agent=Mozilla/5.0 (Windows; U; Windows NT 5.1;
   * zh-CN; rv:1.7.10) Gecko/20050717 Firefox/1.0.6
   */
  String agent = request.getHeader("USER-AGENT");
  try {
   if ((agent != null) && (-1 != agent.indexOf("MSIE"))) { // IE浏览器
    String newFileName = URLEncoder.encode(filename, "UTF-8");
    newFileName = StringUtils.replace(newFileName, "+", "%20");
    if (newFileName.length() > 150) {
     newFileName = new String(filename.getBytes("GB2312"),
       "ISO8859-1");
     newFileName = StringUtils.replace(newFileName, " ", "%20");
    }
    return newFileName;
   }
   if ((agent != null) && (-1 != agent.indexOf("Mozilla"))) // 火狐浏览器
    return MimeUtility.encodeText(filename, "UTF-8", "B");
   return filename;
  } catch (Exception ex) {
   return filename;
  }
 }

/**
  * 文件下载
  * @author:qiuchen
  * @createTime:2012-6-19
  * @param fileName
  * @param request
  * @param response
  * @return
  * @throws Exception
  */
 @RequestMapping("/download/{fileName}")
 public ModelAndView download(@PathVariable("fileName") String fileName,HttpServletRequest request, HttpServletResponse response)throws Exception {
  request.setCharacterEncoding("UTF-8");

  BufferedInputStream bis = null;  //从文件中读取内容
  BufferedOutputStream bos = null; //向文件中写入内容

  //获得服务器上存放下载资源的地址
  String ctxPath = request.getSession().getServletContext().getRealPath("/")+ "\\" + "fileupload\\";
  //获得下载文件全路径
  String downLoadPath = ctxPath + fileName;
  System.out.println(downLoadPath);
  //如果文件不存在,退出
  File file = new File(downLoadPath);
  if(!file.exists()){
   return null;
  }
  try {
   //获得文件大小
   long fileLength = new File(downLoadPath).length();
   System.out.println(new String(fileName.getBytes("utf-8"), "ISO-8859-1"));
   response.setContentType("text/html;charset=utf-8"); //设置相应类型和编码
   response.setHeader("Content-disposition", "attachment;filename=" + new String(fileName.getBytes("utf-8"), "ISO-8859-1"));
   response.setHeader("Content-Length", String.valueOf(fileLength));

   bis = new BufferedInputStream(new FileInputStream(downLoadPath));
   bos = new BufferedOutputStream(response.getOutputStream());
   //定义文件读取缓冲区
   byte[] buff = new byte[2048];
   int bytesRead;
   //把下载资源写入到输出流
   while (-1 != (bytesRead = bis.read(buff, 0, buff.length))) {
    bos.write(buff, 0, bytesRead);
   }
  } catch (Exception e) {
   e.printStackTrace();
  } finally {
   if (bis != null)
    bis.close();
   if (bos != null)
    bos.close();
  }
  return null;
 }

对于正在复制代码的你，Control+O导入命名包时，以下应该是你喜欢的：
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.net.BindException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.lang.StringUtils;
import org.springframework.stereotype.Controller;
import org.springframework.util.FileCopyUtils;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.multipart.MultipartFile;
import org.springframework.web.multipart.MultipartHttpServletRequest;
import org.springframework.web.multipart.commons.CommonsMultipartFile;
import org.springframework.web.servlet.ModelAndView;
import com.sun.xml.internal.messaging.saaj.packaging.mime.internet.MimeUtility;

原文出处：http://871421448.iteye.com/blog/1564287