Solved

Taking a LONG time for BufferedInputStream to read end of stream

Posted on 2004-04-13
11
419 Views
Last Modified: 2008-01-16
I have created a simple program which will download an image file from a url and write it to a file (yahoo banner gif file).  The problem is that when I go to read the BufferedInputStream from the socket, it takes forever to return -1 (or end of stream) so the program will sit there waiting.  That is the while loop at the end of this program does not halt in a short time.  Any ideas on this one?  Thanks.

try {
      File newFile = new File("test.gif");
      FileOutputStream outstream = new FileOutputStream(newFile);      

      Socket sock = new Socket("us.i1.yimg.com",80);

      DataOutputStream out = new DataOutputStream(sock.getOutputStream());
      InputStream in = sock.getInputStream();
      BufferedInputStream input = new BufferedInputStream(in);            
      byte buffer[] = new byte[8192];      

      String command = "GET http://us.i1.yimg.com/us.yimg.com/i/ww/m6v8c.gif HTTP/1.1 \n";
      command += "Host: us.i1.yimg.com \n\n";                  

      out.write(command.getBytes());

              while((bytesRead = input .read(buffer)) > -1){      //This while loop does not seem to want to end as bytesRead sits there waiting for end of stream
                    outstream.write(buffer,0,bytesRead);
       }
0
Comment
Question by:aomega
  • 4
  • 4
  • 3
11 Comments
 
LVL 92

Expert Comment

by:objects
ID: 10820362
Does it (the loop) halt at all?
It may be that the server is still waiting for the request.
0
 
LVL 9

Expert Comment

by:mmuruganandam
ID: 10820419
Why don't you use URL and URLConnection to do that?

That would take care of all these problems.


Regards,
Muruga
0
 
LVL 9

Expert Comment

by:mmuruganandam
ID: 10820448
File newFile = new File("test.gif");
FileOutputStream outstream = new FileOutputStream(newFile);    

URL url = new URL("http://us.i1.yimg.com/us.yimg.com/i/ww/m6v8c.gif");
URLConnection conn = url.openConnection();

byte buffer[] = new byte[8192];
BufferedInputStream input = new BufferedInputStream(conn.getInputStream());

while((bytesRead = input .read(buffer)) > -1)
{
    outstream.write(buffer,0,bytesRead);
}

input.close();
outstream.close();



Regards,
Muruga
0
Free Tool: Subnet Calculator

The subnet calculator helps you design networks by taking an IP address and network mask and returning information such as network, broadcast address, and host range.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

 

Author Comment

by:aomega
ID: 10820485
objects, in this particular case I am not sure if the loop halts at all.  However, I have tried connecting to other addresses and some may halt in say 5 minutes.

mmuruganandam, yes using the HttpURLConnection class would work.  However, this needs to be implemented using sockets.  Thanks.
0
 
LVL 9

Expert Comment

by:mmuruganandam
ID: 10820496
use socket.soTimeOut(<milliseconds>); // this will timeout when the connection is idle for that many milliseconds.
0
 
LVL 92

Expert Comment

by:objects
ID: 10820520
Add some debug to your loop to check if any data is being read:

      System.out.println("Reading response");
      while((bytesRead = input .read(buffer)) > -1){      //This while loop does not seem to want to end as bytesRead sits there waiting for end of stream
           System.out.println("Read: "+bytesRead);
           outstream.write(buffer,0,bytesRead);
      }

If none is being read then I'd say the server has not returned response.
0
 

Author Comment

by:aomega
ID: 10820585
objects, I have tried printing out bytesRead and it is indeed reading all the bytes that make up the image.  When the loop goes back to read more from the stream when there is none left, it will sit and wait.  When I force an end with ctrl-C i can even successfully view the image.

mmuruganandam, I have tried to implement this with the socket timeout and it will throw the exception when the socket indeed times out.  However I was wondering if there was another solution to this (aside from using URL's) since I am wondering myself.  Thanks.
0
 
LVL 9

Expert Comment

by:mmuruganandam
ID: 10820653
If the problem persists, you can think of running this in a thread and timeout the thread after some idle period

0
 
LVL 92

Accepted Solution

by:
objects earned 125 total points
ID: 10820726
you may need to read the response to determine the content length to know when all the data has been read.
0
 

Author Comment

by:aomega
ID: 10820965
objects, thanks for the suggestion.  That is exactly what I did and it works perfectly now.
0
 
LVL 92

Expert Comment

by:objects
ID: 10821002
0

Featured Post

Free Tool: Path Explorer

An intuitive utility to help find the CSS path to UI elements on a webpage. These paths are used frequently in a variety of front-end development and QA automation tasks.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
V.simple question about Android packages and libraries 1 29
oracle 11g 23 106
jboss wildfly 10.1 10 219
Adding multiple JVM environments to RedHat 6 7 45
Java Flight Recorder and Java Mission Control together create a complete tool chain to continuously collect low level and detailed runtime information enabling after-the-fact incident analysis. Java Flight Recorder is a profiling and event collectio…
Introduction This article is the second of three articles that explain why and how the Experts Exchange QA Team does test automation for our web site. This article covers the basic installation and configuration of the test automation tools used by…
Viewers learn about the third conditional statement “else if” and use it in an example program. Then additional information about conditional statements is provided, covering the topic thoroughly. Viewers learn about the third conditional statement …
This tutorial covers a practical example of lazy loading technique and early loading technique in a Singleton Design Pattern.

808 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question