Servlet code to download text file from website – Java
Here’s a servlet code example to download a text file from a website.
For example
Let’s say a text file named “testing.txt” , and you want to let user download it with a URL , for example “http://localhost:8080/servlet/DownloadDemo” .
1. Create a text file named “testing.txt” , put it into the project root folder.
\--servlet (project root folder)
\--testing.txt (download file here)
\--WEB-INF
\--web.xml
2. Servlet code
package com.mkyong;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class ServletDownloadDemo extends HttpServlet{
private static final int BYTES_DOWNLOAD = 1024;
public void doGet(HttpServletRequest request,
HttpServletResponse response) throws IOException{
response.setContentType("text/plain");
response.setHeader("Content-Disposition",
"attachment;filename=downloadname.txt");
ServletContext ctx = getServletContext();
InputStream is = ctx.getResourceAsStream("/testing.txt");
int read=0;
byte[] bytes = new byte[BYTES_DOWNLOAD];
OutputStream os = response.getOutputStream();
while((read = is.read(bytes))!= -1){
os.write(bytes, 0, read);
}
os.flush();
os.close();
}
}
Note
The “getResourceAsStream()” method with a forward slash (“/”), which represent the root of your web application.
The “getResourceAsStream()” method with a forward slash (“/”), which represent the root of your web application.
3. Web deployment descriptor
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>serlvetdemo</display-name>
<servlet>
<servlet-name>ServletName</servlet-name>
<servlet-class>com.mkyong.ServletDownloadDemo</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ServletName</servlet-name>
<url-pattern>/DownloadDemo</url-pattern>
</servlet-mapping>
</web-app>
4. Compiled it and copy to the Tomcat folder
\--Tomcat
\--webapps
\--servlet
\-- testing.txt (download file)
\--WEB-INF
\--web.xml
\--classes
\--com
\--mkyong
\--ServletDownloadDemo.class
4. Done , access URL http://localhost:8080/servlet/DownloadDemo , it will prompts user to download the text file automatically.
Note
You may interest this file download example in Struts 1.x
You may interest this file download example in Struts 1.x
Hi,
I am getting NullPointerException at is.read please help me in this regard.
I have a code like:
String recommendedFilename = getLocalEntityName();
response.setContentType(“application/x-download”);
response.setContentLength(exportData.length);
response.setHeader(“Content-Disposition”, “attachment; filename=” + recommendedFilename);
But the when filename (the value for recommendedFilename) contains japanese characters, then the default filename in the “Open/Save” dialogue is not proper japanese. All the japanese characters are coming as junk. Can you please help?
Above code works fine if I have to download file using browser. Kindly help me on downloading file without using browser. i.e. through servlet client.
I am using “URL url = new URL(reqUrl);
URLConnection uc = url.openConnection();” to access servlet. Kindly give some inputs. Thank you.
Please provide git link as well. that will help much
vo beja sua bok seu lindo, obrigado pelo codigo
Sir
the above code doesn’t work over https.
I have configured my apache tomcat for ssl but now i am not able to download files. Pls suggest the changes. With http it works but fails over https.
Thanku
you are watch video
Servlets Demo
https://www.youtube.com/watch?v=tZDNtXdyghA&list=PLWw624ESjD08dNrNpzVVk-P6TMAoaevz5
It looks like os.flush() and os.close() is obsolete here since servlet container will do it anyway. As per http://stackoverflow.com/questions/5043657/do-i-need-to-flush-the-servlet-outputstream
Your tutorials help me a lot…. Thank u….
works fine ,thanks for sharing ,one query i have is that “InputStream is” should be closed or not? because at my end i am not able to delete the file latter since JVM still has it open mode, in my code i have opened a scriplet in jsp and put the above code in it.
tanq very much 🙂
but how to make my browser ask me to download the file ?
I am truly thankful to the holder of this web page who has shared this
impressive post at at this time.
Thanks the code is working but I want to know if we want to get put an anchor in html file and by clicking we start download how to retrieve the name from anchor link…pls help
You saved my life again. Thank you.
hi mkyong,
i have a small requirement in downloading file from linux, can you tel me how to do….
Hi,
do you know if it’s possible to download the file in a specific directory (specified by the servlet) without asking anything to the user?
hahaha I didnt even get what extention I should save these files into or where I should put it to..
thanks a lot for this post
but in need something different…
I want that the text file is showed in the browser and not downloaded,
what is the change that i have to do in the code?
thanks
where i have to place class file? how to get com.mkyong package?
Someone necessarily help to make critically articles I might state. That is the very first time I frequented your web page and to this point? I surprised with the research you made to create this actual publish amazing. Fantastic job!
I have a situation where i have created my PDF file in a servlet using bytearrayoutputstream. When run on its own the servlet does work and produces my PDF file, however, it is an instance where i need the file to be opened from a JSP on a button commmand. Is anyone familiar with how I would go about that?
i’m using jBoss server so can any one help me for that…
Servlet is standard, it should work in jboss.
If u dont know then please dont try to send wri=ong data
Great article! Thanks a lot
Thanks for posting such a useful example.
Hello,
My name is Ming. I am a student at GSU. I find th eprogram very useful but I’d like to ask the author and other forum members a question regarding download a PDF file to my pc. I’d like to know if this program works for download PDF file to my pc ? Thanks in advance.
yes, the concept is apply to any file type, but you may need just change the “response.setContentType(“text/plain”);” to “application/octet-stream” or other content type to suit your need.
Thank you, for the note. If the text file have space padding between the text then if we use “text/plain” content type and download a file,all the space padding reduced to single space. And if we use “application/octet-stream” then space padding will remain intact.
really good information thanks admin
Thanks Nice Post. I added this thread to favorites.
what is package com.mkyong? and where can i download it?
can it used to open a web browser with java program?
thanks
1. “package com.mkyong” is just the source code packaging structure, refer to http://java.sun.com/docs/books/jls/third_edition/html/packages.html
2. To open a web browser, pls refer to this example
https://mkyong.com/java/open-browser-in-java-windows-or-linux/
Thanks for posting such a useful example.
Yor this code is not working for me it just creates the file but the contents are not downloading……
Plz reply as soon as possible
Thanks in Adv.
🙂
The code is well tested, why not sharing your code, may be something wrong in your code?