使用Servlet实现下载文件的功能

84 阅读 0 评论 56 点赞

我是靠谱客的博主可靠宝马，这篇文章主要介绍使用Servlet实现下载文件的功能，现在分享给大家，希望可以做个参考。

在前台有一个下载链接，比如

复制代码

1
<a href="DownLoadServlet">下载</a> <br/>

使用Servlet实现下载：

复制代码

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.URLEncoder;
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 {
public DownLoadServlet() {
super();
}
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here

}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request,response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//处理请求
//读取要下载的文件

File f = new File("E:/好久不见.mp3");
if(f.exists()){
FileInputStream
fis = new FileInputStream(f);
String filename=URLEncoder.encode(f.getName(),"utf-8"); //解决中文文件名下载后乱码的问题

byte[] b = new byte[fis.available()];
fis.read(b);
response.setCharacterEncoding("utf-8");
response.setHeader("Content-Disposition","attachment; filename="+filename+"");
//获取响应报文输出流对象

ServletOutputStream
out =response.getOutputStream();
//输出

out.write(b);
out.flush();
out.close();
}
}
/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here

}
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.URLEncoder;
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 {
public DownLoadServlet() {
super();
}
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here


}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request,response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//处理请求
//读取要下载的文件

File f = new File("E:/好久不见.mp3");
if(f.exists()){
FileInputStream
fis = new FileInputStream(f);
String filename=URLEncoder.encode(f.getName(),"utf-8"); //解决中文文件名下载后乱码的问题

byte[] b = new byte[fis.available()];
fis.read(b);
response.setCharacterEncoding("utf-8");
response.setHeader("Content-Disposition","attachment; filename="+filename+"");
//获取响应报文输出流对象

ServletOutputStream
out =response.getOutputStream();
//输出


out.write(b);
out.flush();
out.close();
}
}
/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here


}
}