forked from srieger/verteilte-systeme-bsc-ai-examples
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
55 lines
2.5 KiB
55 lines
2.5 KiB
package verteiltesysteme.socket.timecounter;
|
|
|
|
import java.io.BufferedReader;
|
|
import java.io.InputStreamReader;
|
|
import java.net.DatagramPacket;
|
|
import java.net.DatagramSocket;
|
|
import java.net.InetAddress;
|
|
import java.text.DateFormat;
|
|
import java.text.SimpleDateFormat;
|
|
import java.util.Date;
|
|
|
|
class UDPTimeCounterClient {
|
|
public static void main(String args[]) throws Exception {
|
|
String hostname = "";
|
|
int udpPort = 36038;
|
|
BufferedReader inFromUser = new BufferedReader(new InputStreamReader(System.in));
|
|
DatagramSocket clientSocket = new DatagramSocket();
|
|
byte[] sendData = new byte[1024];
|
|
byte[] receiveData = new byte[1024];
|
|
DateFormat df = new SimpleDateFormat("dd.MM.yyyy HH:mm:ss");
|
|
|
|
System.out.println("Bitte geben Sie die Server-Adresse ein: ");
|
|
hostname = inFromUser.readLine();
|
|
InetAddress IPAddress = InetAddress.getByName(hostname);
|
|
System.out.println("Bitte geben Sie eine Zahl ein: ");
|
|
Long number = new Long(inFromUser.readLine());
|
|
sendData = number.toString().getBytes();
|
|
|
|
System.out.println(System.lineSeparator());
|
|
long timestampStart = System.currentTimeMillis();
|
|
System.out.println("Zeit vor Versand = " + timestampStart + " ms, " + df.format(new Date(timestampStart)));
|
|
DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length, IPAddress, udpPort);
|
|
clientSocket.send(sendPacket);
|
|
long timestampSent = System.currentTimeMillis();
|
|
System.out.println("Zeit nach Versand = " + timestampSent + " ms, " + df.format(new Date(timestampSent)));
|
|
DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);
|
|
|
|
clientSocket.receive(receivePacket);
|
|
|
|
long timestampEnd = System.currentTimeMillis();
|
|
System.out.println("Zeit nach Empfang = " + timestampEnd + " ms, " + df.format(new Date(timestampEnd)));
|
|
long delay = timestampEnd - timestampStart;
|
|
System.out.println("Delay = " + delay + " ms");
|
|
System.out.println(System.lineSeparator());
|
|
|
|
String result = new String(receivePacket.getData());
|
|
System.out.println("Ausgabe vom Server:" + System.lineSeparator() + result);
|
|
long timestampServer = new Long(result.split(" ")[2]).longValue();
|
|
float oneWayDelayEstimate = (timestampEnd - timestampSent) / 2;
|
|
float timestampSkew = timestampServer - timestampSent - oneWayDelayEstimate;
|
|
System.out.println("Zeitversatz zwischen Server und Client ca. = " + timestampSkew + " ms");
|
|
System.out.println(System.lineSeparator());
|
|
clientSocket.close();
|
|
}
|
|
}
|