最近做了一個檔案上傳、下載、與線上開啟檔案的功能，剛開始對檔案上傳的介面中含有其它表單（例如輸入框、密碼等）在上傳的過程中遇到了許多問題，下面我寫了一個同時實現檔案上傳、下載、線上開啟檔案的測試程式。
首先請看效果圖：

   核心程式碼： 

[java] view plaincopy
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()) { // 檔案  
                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 { // 表單  
                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
[html] view plaincopy
<%@ page language=”java” contentType=”text/html; charset=UTF-8”
pageEncoding=”UTF-8”%>




Insert title here





檔案一：

檔案二：

上傳者:

日期:

download.jsp
[html] view plaincopy
<%@ page language=”java” contentType=”text/html; charset=UTF-8”
pageEncoding=”UTF-8”%>