Dateien hochladen nach „praktkum3“

praktkum3/DiningPhilosophers.java

+import java.util.concurrent.locks.Lock;
+import java.util.concurrent.locks.ReentrantLock;
+
+public class DiningPhilosophers {
+
+    // Anzahl der Philosophen
+    private static final int NUM_PHILOSOPHERS = 5;
+
+    public static void main(String[] args) {
+        Philosopher[] philosophers = new Philosopher[NUM_PHILOSOPHERS];
+        Fork[] forks = new Fork[NUM_PHILOSOPHERS];
+
+        // Initialisiere Gabeln
+        for (int i = 0; i < NUM_PHILOSOPHERS; i++) {
+            forks[i] = new Fork(i);
+        }
+
+        // Initialisiere Philosophen
+        for (int i = 0; i < NUM_PHILOSOPHERS; i++) {
+            Fork leftFork = forks[i];
+            Fork rightFork = forks[(i + 1) % NUM_PHILOSOPHERS];
+
+            // Um Deadlock zu vermeiden, greift der letzte Philosoph zuerst zur rechten Gabel.
+            if (i == NUM_PHILOSOPHERS - 1) {
+                philosophers[i] = new Philosopher(i, rightFork, leftFork);
+            } else {
+                philosophers[i] = new Philosopher(i, leftFork, rightFork);
+            }
+
+            new Thread(philosophers[i], "Philosopher-" + i).start();
+        }
+    }
+}
+
+class Fork {
+
+    private final int id;
+    private boolean inUse;
+
+    // Konstruktor
+    public Fork(int id) {
+        this.id = id;
+        this.inUse = false;
+    }
+
+    // Liefert die ID der Gabel zurück
+    public int getId() {
+        return id;
+    }
+
+    // Gabel aufnehmen
+    public synchronized boolean take() {
+        if (!inUse) {
+            inUse = true; // Gabel ist jetzt in Benutzung
+            try {
+                Thread.sleep(1000); // 1 Sekunde warten, um die Gabel aufzunehmen
+            } catch (InterruptedException e) {
+                Thread.currentThread().interrupt();
+            }
+            return true;
+        }
+        return false; // Gabel ist bereits in Benutzung
+    }
+
+    // Gabel freigeben
+    public synchronized void put() {
+        inUse = false; // Gabel freigeben
+    }
+
+    @Override
+    public String toString() {
+        return "Fork-" + id;
+    }
+}
+
+
+class Philosopher implements Runnable {
+    private final int id;
+    private final Fork leftFork;
+    private final Fork rightFork;
+
+    public Philosopher(int id, Fork leftFork, Fork rightFork) {
+        this.id = id;
+        this.leftFork = leftFork;
+        this.rightFork = rightFork;
+    }
+
+    @Override
+    public void run() {
+        try {
+
+            // Linke Gabel aufnehmen
+            System.out.println("Philosopher-" + id + " is trying to get " + leftFork);
+            while (!leftFork.take()) {
+                Thread.yield(); // Busy waiting entschärfen
+            }
+            System.out.println("Philosopher-" + id + " got " + leftFork);
+
+            // Rechte Gabel aufnehmen
+            System.out.println("Philosopher-" + id + " is trying to get " + rightFork);
+            while (!rightFork.take()) {
+                Thread.yield(); // Busy waiting entschärfen
+            }
+            System.out.println("Philosopher-" + id + " got " + rightFork);
+
+            // Philosoph isst
+            System.out.println("Philosopher-" + id + " is eating.");
+            Thread.sleep(2000); // 2 Sekunden essen
+
+            // Gabeln freigeben
+            leftFork.put();
+            System.out.println("Philosopher-" + id + " put down " + leftFork);
+            rightFork.put();
+            System.out.println("Philosopher-" + id + " put down " + rightFork);
+
+            // Philosoph beendet das Essen
+            System.out.println("Philosopher-" + id + " finished eating.");
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+            System.out.println("Philosopher-" + id + " was interrupted.");
+        }
+    }
+}
+
+

praktkum3/DistributedSorterClient.java

+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.io.PrintWriter;
+import java.net.Socket;
+import java.util.Scanner;
+
+public class DistributedSorterClient {
+    public static void main(String[] args) {
+        new DistributedSorterClient().run();
+    }
+
+    private void run() {
+        Scanner scanner = new Scanner(System.in);
+        while (true) {
+            System.out.print("Enter a string to sort (or press Enter to quit): ");
+            String line = scanner.nextLine();
+            if (line.isEmpty()) break;
+
+            // Senden und Empfangen der sortierten Zeile
+            String sortedLine = sort(line);
+            if (sortedLine != null) {
+                System.out.println("Sorted: " + sortedLine);
+            } else {
+                System.out.println("Error communicating with server.");
+            }
+        }
+        scanner.close();
+    }
+
+    private String sort(String line) {
+        String response = "";
+        try (Socket socket = new Socket("localhost", 12345);
+             PrintWriter out = new PrintWriter(socket.getOutputStream(), true);
+             BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()))) {
+
+            // Sende die Eingabezeile an den Server
+            out.println(line);
+
+            // Warte auf die Antwort des Servers
+            response = in.readLine();
+
+        } catch (Exception e) {
+            System.err.println("Error communicating with server: " + e.getMessage());
+            return null;
+        }
+        return response;
+    }
+}

praktkum3/DistributedSorterServer.java

+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.io.PrintWriter;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.util.Arrays;
+
+public class DistributedSorterServer implements Runnable {
+    private final Socket clientSocket;
+
+    // Konstruktor
+    public DistributedSorterServer(Socket clientSocket) {
+        this.clientSocket = clientSocket;
+    }
+
+    public static void main(String[] args) {
+        final int port = 12345;
+
+        try (ServerSocket serverSocket = new ServerSocket(port)) {
+            System.out.println("Distributed Sorter Server is running on port " + port);
+
+            while (true) {
+                // Warten auf neue Verbindung
+                Socket client = serverSocket.accept();
+                System.out.println("New client connected: " + client.getInetAddress());
+
+                // Neuen Thread starten, um die Client-Anfrage zu bearbeiten
+                Thread thread = new Thread(new DistributedSorterServer(client));
+                thread.start();
+            }
+        } catch (Exception e) {
+            System.err.println("Error: " + e.getMessage());
+        }
+    }
+
+    @Override
+    public void run() {
+        try (
+                BufferedReader in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
+                PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true)
+        ) {
+            String inputLine;
+
+            // Verarbeite alle Nachrichten vom Client
+            while ((inputLine = in.readLine()) != null) {
+                System.out.println("Received: " + inputLine);
+
+                // Sortiere die Buchstaben im String
+                String sortedLine = sortCharacters(inputLine);
+                System.out.println(inputLine + " -> " + sortedLine);
+
+                // Antwort zurück an den Client senden
+                out.println(sortedLine);
+            }
+        } catch (Exception e) {
+            System.err.println("Error handling client: " + e.getMessage());
+        } finally {
+            try {
+                clientSocket.close();
+                System.out.println("Client disconnected.");
+            } catch (Exception e) {
+                System.err.println("Error closing client socket: " + e.getMessage());
+            }
+        }
+    }
+
+    // Sortiermethode für die Zeichen im String
+    private String sortCharacters(String input) {
+        char[] chars = input.toCharArray();
+        Arrays.sort(chars);
+        return new String(chars);
+    }
+}