最近做了一个文件上传、下载、与在线打开文件的功能，刚开始对文件上传的界面中含有其它表单（例如输入框、密码等）在上传的过程中遇到了许多问题，下面我写了一个同时实现文件上传、下载、在线打开文件的测试程序。
首先请看效果图：
核心代码：
package com.jefry;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
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;
/**
* Servlet implementation class FileUpload
*/
public class FileUpload extends HttpServlet {
private static final long serialVersionUID = 1L;
private static final String fileDir = "F:/";
/**
* Default constructor.
*/
public FileUpload() {
}
protected void doGet(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
String aFileName = request.getParameter("fileName");
String online = request.getParameter("online");
FileInputStream in = null;
ServletOutputStream out = null;
boolean isOnLine = online != null ? true : false ;
try {
if(isOnLine){
URL u = new URL("file:///"+fileDir + aFileName);
response.setContentType(u.openConnection().getContentType());
response.setHeader("Content-Disposition", "inline; filename="+aFileName);
}
else{
response.setContentType("application/x-msdownload");
response.setHeader("Content-Disposition", "attachment; filename=" + aFileName);
}
in = new FileInputStream(fileDir + aFileName);
out = response.getOutputStream();
out.flush();
int aRead = 0;
while ((aRead = in.read()) != -1 & in != null) {
out.write(aRead);
}
out.flush();
} catch (Throwable e) {
e.printStackTrace();
} finally {
try {
in.close();
out.close();
} catch (Throwable e) {
e.printStackTrace();
}
}
}
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
try {
DiskFileItemFactory fileFactory = new DiskFileItemFactory();
ServletFileUpload fu = new ServletFileUpload(fileFactory);
List fileItems = fu.parseRequest(request);
Iterator iter = fileItems.iterator();
String uploader = null;
String date = null;
List<String> fileNames = new ArrayList<String>();
while (iter.hasNext()) {
FileItem item = (FileItem) iter.next();
if (!item.isFormField()) { // 文件
String oldFileName = item.getName();
String newFileName = null;
int delimiter = oldFileName.lastIndexOf("/");
if (delimiter == -1)
newFileName = oldFileName.substring(delimiter + 1);
else
newFileName = oldFileName;
fileNames.add(newFileName);
item.write(new File(fileDir + newFileName));
} else { // 表单
String fieldName = item.getFieldName();
if ("uploader".equals(fieldName)) {
uploader = item.getString();
} else if ("date".equals(fieldName)) {
date = item.getString();
}
}
}
request.setAttribute("fileNames",fileNames);
request.getRequestDispatcher("download.jsp").forward(request, response);
} catch (Exception e) {
}
}
}
index.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!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>Insert title here</title>
</head>
<body>
<form action="FileUpload" method="post" enctype="multipart/form-data">
<br>
文件一：<input type="file" name="file1" /> <br>
文件二：<input type="file" name="file2" /> <br>
上传者:<input type="text" name="uploader"/> <br>
日期:<input type="text" name="date"/> <br>
<input type="submit" value="提交"/>
</form>
</body>
</html>
download.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@page import="java.util.List"%><html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<br>
--------------直接下载------------
<br>
<%
List<String> fileNames = (List<String> )request.getAttribute("fileNames");
for(String fileName : fileNames) {
%>
<form action="FileUpload" method="get">
<input type="hidden" name="fileName" value="<%=fileName %>" />
<input type="submit" value="下载:<%=fileName %>" />
</form>
<%
}
%>
<br>
--------------直接打开---------
<%
for(String fileName : fileNames) {
%>
<form action="FileUpload" method="get">
<input type="hidden" name="fileName" value="<%=fileName %>" />
<input type="hidden" name="online" value="yes" />
<input type="submit" value="打开:<%=fileName %>" />
</form>
<%
}
%>
</br>
</body>
</html>