javaWeb實現檔案下載
阿新 • • 發佈：2019-01-06
今天學習了JavaWeb實現檔案下載，為了以後方便查詢並讓需要的人學習，今兒把程式碼獻上！！！！
首先寫一個jsp頁面
字型加粗的為主要內容：
download.jsp：
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>檔案下載</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<a href="/download/DownloadServlet?filename=1.jpg">檔案下載</a> 然後在定義一個Servlet，如下：
DownloadServlet：
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setCharacterEncoding("UTF-8"); //設定ContentType欄位值 response.setContentType("text/html;charset=utf-8"); //獲取所要下載的檔名稱 String filename = request.getParameter("filename"); //下載檔案所在目錄 String folder = "/filename/"; //通知瀏覽器以下載的方式開啟 response.addHeader("Content-type", "appllication/octet-stream"); response.addHeader("Content-Disposition", "attachment;filename="+filename); //通知檔案流讀取檔案 InputStream in = getServletContext().getResourceAsStream(folder+filename); //獲取response物件的輸出流 OutputStream out = response.getOutputStream(); byte[] buffer = new byte[1024]; int len; //迴圈取出流中的資料 while((len = in.read(buffer)) != -1){ out.write(buffer,0,len); } }
效果圖：
用到的架包：commons-fileupload-1.3.1.jar、commons-io-2.4.jar