import java.io$.$FileWriter;

import java.io$.$IOException;

import java.util.Timer;

import java.util.TimerTask;

public class DASHClient $\{$

private static final String DASH$\_$MANIFEST$\_$URL $="$https:$//$ftp$.$itec.aau.at$/$datasets$/$DASHDataset$2014/$BigBuckBunny$/10$sec$/$BigBuckBunny$\_10$s$\_$onDemand$\_2014\_05\_09.$mpd$"$;

private static final int BUFFER$\_$THRESHOLD $=2$; $//$ Buffer threshold for underrun detection

private double bufferDuration $=0$;

private int chosenRepresentation $=2$; $//$ Initial representation ID $($e$.$g$.,750$ kbps$)$

private double totalBitrate $=0$;

private int underrunCount $=0$;

private int underrunDuration $=0$;

public static void main$($String$[]$ args$)\{$

DASHClient client $=$ new DASHClient$()$;

client.startStreaming$()$;

$\}$

private void startStreaming$()\{$

Timer timer $=$ new Timer$()$;

timer.scheduleAtFixedRate$($new TimerTask$()\{$

@Override

public void run$()\{$

try $\{$

$//$ Fetch DASH manifest $($you can use HTTP client libraries$)$

String manifestContent $=$ fetchDASHManifest$($DASH$\_$MANIFEST$\_$URL$)$;

$//$ Parse manifest and choose representation $($simplified for demo$)$

$//$ Assume representation IDs: $0(250$ kbps$),1(500$ kbps$),2(750$ kbps$),$ etc.

chosenRepresentation $=$ getNextRepresentation$($chosenRepresentation$)$;

$//$ Simulate downloading video segments $($you$\text{'}$d use a library$)$

bufferDuration $+=1$;

totalBitrate $+=$ getBitrateForRepresentation$($chosenRepresentation$)$;

$//$ Check for underrun $($buffer depletion$)$

if $($bufferDuration $<$ BUFFER$\_$THRESHOLD$)\{$

underrunCount$++$;

underrunDuration$++$;

$\}$

$//$ Record data points $($write to a CSV file$)$

recordDataPoint$($System$.$currentTimeMillis$(),$ bufferDuration, chosenRepresentation,

getBitrateForRepresentation$($chosenRepresentation$))$;

$\}$ catch $($IOException e$)\{$

e$.$printStackTrace$()$;

$\}$

$\}$

$\},0,1000)$; $//$ Run every second $($simulating real$-$time streaming$)$

$\}$

private String fetchDASHManifest$($String url$)$ throws IOException $\{$

$//$ Implement fetching logic $($e$.$g$.,$ using HttpURLConnection or HttpClient$)$

$//$ Return the manifest content as a string

return $""$; $//$ Placeholder for demonstration

$\}$

private int getNextRepresentation$($int currentRepId$)\{$

$//$ Implement logic to switch to the next representation $($e$.$g$.,$ round$-$robin$)$

$//$ For simplicity, let's assume we cycle through representations: $0,1,2,...$

return $($currentRepId $+1)\%3$; $//$ Assuming $3$ representations $(250,500,750$ kbps$)$

$\}$

private int getBitrateForRepresentation$($int repId$)\{$

$//$ Map representation ID to actual bit rate $($you can adjust this based on your data$)$

switch $($repId$)\{$

case $0$:

return $250$;

case $1$:

return $500$;

case $2$:

return $750$;

$//$ Add more cases for other representations if needed

default:

return $0$;

$\}$

$\}$

private void recordDataPoint$($long timestamp, double buffer, int repId, int bitrate$)\{$

$//$ Create or open a CSV file for recording data points

try $($FileWriter writer $=$ new FileWriter$("$streaming$\_$data.csv$",$ true$))\{$

$//$ Append data to the file

writer.append$($String$.$format$("\%$d$,\%\mathrm{.}2$f$,\%$d$,\%$d$\%$n$",$ timestamp, buffer, repId, bitrate$))$;

$\}$ catch $($IOException e$)\{$

e$.$printStackTrace$()$;

$\}$

$\}$

$\}$

above code is just simulating the real the time streaming instead of this write a code which actualy streams the given mpd file link and records the real time data $.$