JSP下载服务器文件的方法

%@page import="java.io.FileInputStream"%>
!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
%@page language="java" contentType="text/html; charset=UTF-8"%>
%@page import="com.ecc.emp.core.Context" %>
%@page import="java.io.File" %>
%@ include file="http://www.xxxx.com/head.jsp"%>
%
  boolean loadFlag = false;
  ServletOutputStream ou = null;
  FileInputStream fis = null;
  try{  
    Context context=(Context)request.getAttribute("context");
    String accountFilePath = (String)context.getDataValue("accountFilePath");
    //String accountFilePath ="E:/ComeBack/Acc_BOS_CM/WebContent/upload/product/1336873410414custormerStatement.txt";
    //String accountFileName = (String)context.getDataValue("accountFileName");
    String displayFileName = (String)context.getDataValue("displayFileName");
    //String displayFileName ="custormerStatement.txt";
    String fullPath =accountFilePath;
    response.reset();
      response.setContentType("charset=UTF-8");
    response.setContentType("text/HTML");
    //response.setContentType("application/vnd.ms-excel");    
    String filename = new String(displayFileName.getBytes("gb2312"), "ISO8859-1");
    response.setHeader("Content-Disposition","attachment; filename=" + filename);
    //解决HTTPS不能下载的问题
    response.setHeader("Cache-Control","public");    
    ou = response.getOutputStream();
    File file = new File(fullPath);
    fis = new FileInputStream(file);    
    try {
      if (fis != null) {
        int filelen = fis.available();
        byte a[] = new byte[filelen];
        fis.read(a);
        ou.write(a);
        ou.flush();
      }      
      loadFlag=true;
    } catch (Exception e) {
      System.out.println("Excel is not exist!");
    }
    out = pageContext.pushBody();
  }catch(Exception e){
    e.printStackTrace();
  }finally{
    try {
      fis.close();
      ou.close();
      ou = null;
      response.flushBuffer();
    } catch (Exception e) {
      // TODO 自动生成 catch 块
      e.printStackTrace();
    }
  }
%>