FileTransferServerUDPjlibcnds.java

//package experiment2;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.*; // we use Sockets
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;

public class FileTransferServerUDPjlibcnds {

    private static final String SOURCESMALL = "/home/sven/IdeaProjects/runServer/src/main/java/source_small.txt";
    private static final String SOURCEBIG = "/home/sven/IdeaProjects/runServer/src/main/java/source_large.txt";

    
    public static void main(String args[]) throws Exception{
        // Arguments: port & filename
        int srvPort = Integer.parseInt(args[0]); // server UDP port
        String filename = args[1]; // server Name
        int counterEntry=0;
        int counterFile = 0;

	    // Open special datagramm socket from jlibcnds library, do not change this
	    javax.net.DatagramSocket dtgSock;
        dtgSock = new javax.net.DatagramSocket(srvPort);

        byte[] buf = new byte[4000];

	    java.io.FileOutputStream fw = new java.io.FileOutputStream(filename);

	    DatagramPacket packet = new DatagramPacket(buf, buf.length);

	    while (true){
            try {
                dtgSock.setSoTimeout(10000);
                dtgSock.receive(packet);
                // if receive an empty packet will indicate end of file
                String data = new String(packet.getData());
                System.out.printf(data);
                if (packet.getLength() == 0) {
                    System.out.println("Leer");
                    break;
                } else {
                    fw.write(packet.getData(), 0, packet.getLength());
                    counterEntry++;
                }
            } catch (IOException e) {
                System.out.println(e.getMessage());
                break;
            }
            //fw.flush();
	    }
        File file = new File(SOURCESMALL);
        byte[] by = new byte[8];
        FileInputStream fileInputStream = new FileInputStream(file);
        int len=0;
        while ((len=(fileInputStream.read(by,0,by.length)))!=-1){
            counterFile++;
        }
        System.out.printf("Es wurden:%d", counterFile - counterEntry);
        System.out.println(" Packete verloren");
        fw.flush();
	    fw.close();
	    dtgSock.close();	// Close the Socket
    }
}