Interrupted AsyncTask, how to handle it?

Question

What I an trying to achieve:

I am downloading a file and showing updates in the Expanded Notification bar's Views. For android

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The problem

How to handle the situation when server gets disconnected while downlading?

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What I have done so far:

When Input stream is read and net gets disconnected, It should throw an exception. But it isnt throwing an exception.

This code here is s simple download loop:

           try{
         while ( (bufferLength = inputStream.read(buffer)) > 0 )
                {  


                    fileOutput.write(buffer, 0, bufferLength);  
                    //add up the size so we know how much is downloaded  
                    downloadedSize += bufferLength;
                    percent=(int)(100 *( (float)downloadedSize/totalSize ));

                    Log.i("Downloaded", String.valueOf(downloadedSize) );
                }

                }
                ucon.disconnect();
            return 1;
        }
            catch (IOException e) {
                Log.d("Download", "Error: " + e);
               return 2;
            }

I am stunned, why isnt it throwing an exception. What is a work around?

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