【ZT】Jsp/Servlet:实现文件上传与下载【三】

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6．测试

download.jsp显示下载选项，LoadFile.java（Servlet）负责下载文件。

download.jsp

<html>

<head>

<title>download page</title>

</head>

<body>

<a href=loadFile>Download:test.zip</a>

</body>

</html>

LoadFile.java

package com.zj.sample;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.OutputStream;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

public class LoadFile extends HttpServlet {

public void doGet(HttpServletRequest request, HttpServletResponse response)

throws IOException, ServletException {

OutputStream o = response.getOutputStream();

byte b[] = new byte[1024];

// the file to download.

File fileLoad = new File("d:/temp", "test.rar");

// the dialogbox of download file.

response.setHeader("Content-disposition", "attachment;filename="

+ "test.rar");

// set the MIME type.

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

// get the file length.

long fileLength = fileLoad.length();

String length = String.valueOf(fileLength);

response.setHeader("Content_Length", length);

// download the file.

FileInputStream in = new FileInputStream(fileLoad);

int n = 0;

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

o.write(b, 0, n);

}

public void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {

doGet(request, response);

}

web.xml（注册servlet）

<servlet-name>LoadFileServlet</servlet-name>

<servlet-class>com.zj.sample.LoadFile</servlet-class>

</servlet>

<servlet-mapping>

<servlet-name>LoadFileServlet</servlet-name>

<url-pattern>/loadFile</url-pattern>

</servlet-mapping>