java中一个简单的下载示例

时间:2021-04-03 20:51:54

首先在tomcat服务器下的webapps的download项目下建一个doc文件夹,再建个test.doc.防止控指针异常

java中一个简单的下载示例

DownLoad.java代码

 1 package com.down;
2
3 import java.io.IOException;
4 import java.io.InputStream;
5
6 import javax.servlet.ServletException;
7 import javax.servlet.ServletOutputStream;
8 import javax.servlet.annotation.WebServlet;
9 import javax.servlet.http.HttpServlet;
10 import javax.servlet.http.HttpServletRequest;
11 import javax.servlet.http.HttpServletResponse;
12
13 @WebServlet(
14 name="download",
15 urlPatterns={"/test"}
16 )
17 public class DownLoad extends HttpServlet {
18 @Override
19 protected void doPost(HttpServletRequest req, HttpServletResponse resp)
20 throws ServletException, IOException {
21 doGet(req, resp);
22 }
23 @Override
24 protected void doGet(HttpServletRequest request, HttpServletResponse response)
25 throws ServletException, IOException {
26 response.setContentType("application/msword");
27 response.addHeader("Content-disposition","attachment;filename=test.doc");
28 InputStream in=getServletContext().getResourceAsStream("/doc/test.doc");
29 ServletOutputStream os=response.getOutputStream();
30 byte[] bytes=new byte[1024];
31 int len=-1;
32 while((len=in.read(bytes))!=-1){
33 os.write(bytes,0,len);
34 }
35 in.close();
36 os.close();
37 }
38 }

运行结果:

java中一个简单的下载示例