niwowl
2010-06-22 10:37
浏览 306
已采纳

jsp+commons-fileupload-1.2.1.jar上传文件出错

问题已经困扰我两天了!那前辈能解决一下小弟感激不尽!

jsp代码 :
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!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=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<FORM METHOD="POST" ACTION="FileUploadServlet" ENCTYPE="multipart/form-data">
<INPUT TYPE="FILE" NAME="FILE1" SIZE="50"><BR>
<INPUT TYPE="SUBMIT" VALUE="Upload">
</FORM>
</body>
</html>

 Servlet代码:

package wl;

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 {
  System.out.println("111");
  final long MAX_SIZE = 3 * 1024 * 1024;// 设置上传文件最大为 3M
  // 允许上传的文件格式的列表
  final String[] allowedExt = new String[] { "jpg", "jpeg", "gif", "txt",
    "doc", "docx", "mp3", "wma", "m4a" };
  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(4096);// 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
  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);//单步执行每次都会在这里出错
  } 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
 }

}
错误页面:

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1条回答 默认 最新

  • nothing2nithing 2010-06-22 12:52
    已采纳

    你doPost()方法里面加上

    response.setHeader("Cache-Control", "no-cache");// 文件头

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