selective-repeat-java/SelectiveRepeatSender.java at master · danyal-s/selective-repeat-java · GitHub

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/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
packageselectiverepeatsender;

importjava.io.BufferedReader;
importjava.io.IOException;
importjava.io.InputStreamReader;
importjava.io.PrintWriter;
importjava.net.ServerSocket;
importjava.net.Socket;
importjava.util.Scanner;

/**
 *
 * @author Danyal
 */
publicclassSelectiveRepeatSender
{
publicstaticvoidmain(String[] args) throwsInterruptedException
 {
Scannerscan = newScanner(System.in);
intsw, sf = 0, sn = 0, m;
System.out.println("Input the value of 'm': ");
m = scan.nextInt();
sw = (int)Math.pow(2, m - 1);
inttimeout = 200;
String[] data = newString[(int)Math.pow(2,m)];
Timeout[] timers = newTimeout[sw];
for(inti = 0; i < data.length; i++)
 {
data[i] = Integer.toString(i);
 } //Generating string data to send.
m = (int)Math.pow(2, m);
try
 {
intportnumber = 2325;
ServerSocketuservice = newServerSocket(portnumber);
System.out.println("Port number is: " + portnumber);
Socketusocket = uservice.accept();
System.out.println("accepted");
BufferedReaderinbuffer = newBufferedReader(newInputStreamReader(usocket.getInputStream()));
PrintWriteroutbuffer = newPrintWriter(usocket.getOutputStream(), true);
long[] timervals = newlong[sw];
for(inti = 0; i < timervals.length; i++)
timervals[i] = Long.MAX_VALUE;
outbuffer.println(Integer.toString(m));
System.out.println("Done writing.");
while(true)//for(int i = 0; i < data.length; i++)
 {
Stringincoming = inbuffer.readLine();
if(incoming.contains("ACK"))
 {
if(incoming.contains("NACK"))
 {
System.out.println(incoming + " received.");
intnackno = Integer.parseInt(incoming.substring(4, incoming.length()));
if(isBetween(nackno, Integer.parseInt(data[sf%m]), Integer.parseInt(data[sn%m]), m))
 {
System.out.println("Sending out " + data[nackno] + ".");
outbuffer.println(data[nackno]);
if(timers[nackno%sw]!=null)
 {
System.out.println("Cancelling timer number " + nackno + ".");
timers[nackno%sw].timer.cancel();
timers[nackno%sw] = null;
 }
System.out.println("Creating new timer in " + nackno);
timers[nackno%sw] = newTimeout(outbuffer, data[nackno], timeout);
 }
 }
else
 {
System.out.println(incoming + " received.");
intackno = Integer.parseInt(incoming.substring(3, incoming.length()));
if(isBetween(ackno, Integer.parseInt(data[sf%m]), Integer.parseInt(data[sn%m]), m))
 {
while(Integer.parseInt(data[sf%m]) != ackno)
 {
System.out.println("Cancelling timer number " + sf%sw + ".");
timers[sf%sw].timer.cancel();
timers[sf%sw] = null;
sf++;
 }
 }
 }
 }
elseif(incoming.contains("FRAME"))
 {
System.out.println("Receieved frame request packet.");
if(sn-sf >= sw)
 {
System.out.println("Window size is already max. Not sending out frame.");
continue;
 }
System.out.println("Sending out frame number " + sn%m);
outbuffer.println(data[sn%m]);
timers[sn%sw] = newTimeout(outbuffer, data[sn%m], timeout);
sn++;
 }
elseif(incoming.equals("FINISH"))
 {
System.out.println("Finished serving the client.");
break;
 }
//sleep(50);
 }
inbuffer.close();
outbuffer.close();
usocket.close();
uservice.close();
System.exit(0);
 }
catch (IOExceptione)
 {
System.out.println(e);
 }
 }
staticbooleanisBetween(intnum, intn1, intn2, intmod)
 {
if(num == n1)
returntrue;

while(n1 != n2)
 {
n1 = (n1 + 1)%mod;
if(num == n1)
returntrue;
 }
returnfalse;
 }
}