我的老是顯示文件不存在下載失敗 是不是在寫文件名稱的時候出錯了呢？

在下載：<a href="download?filname=1.jpg">圖片</a> &nbsp;&nbsp; ${errorResult}

圖片1.jpg在WebContent/images下

package com.java1234.web;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStream;

import javax.servlet.RequestDispatcher;

import javax.servlet.ServletException;

import javax.servlet.ServletOutputStream;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

public class DownloadServlet extends HttpServlet {

/**

*?

*/

private static final long serialVersionUID = 1L;

@Override

protected void doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

//獲取文件下載路徑

String path=getServletContext().getRealPath("/")+"images";//下載的文件都放在images文件目錄下

String filename=request.getParameter("filname");//獲取到從前臺得到的文件名稱

File file=new File(path+filename);//讀取文件

if(file.exists()){

//設(shè)置相應(yīng)類型application/octet-stream

response.setContentType("application/x-msdownload");

//設(shè)置頭信息

response.setHeader("Content-Disposition","attachment=\""+filename+"\"");

InputStream inputStream = new FileInputStream(file);

ServletOutputStream outputStream = response.getOutputStream();

byte b[]=new byte[1024];

int n;

while((n=inputStream.read(b))!=-1){

outputStream.write(b,0,n);

}

//關(guān)閉流，釋放流

outputStream.close();

inputStream.close();

}else{

request.setAttribute("errorResult","文件不存在下載失敗！");

//重定向轉(zhuǎn)發(fā)到j(luò)sp

RequestDispatcher dispatcher=request.getRequestDispatcher("download.jsp");

dispatcher.forward(request,response);

}

}

@Override

protected void doPost(HttpServletRequest request, HttpServletResponse response)?

throws ServletException, IOException {

this.doGet(request, response);

}

}