c

src/src/Chopstick.java

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+public class Chopstick {
+
+}

src/src/Philosopher.java

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+import java.util.Random;
+
+public class Philosopher extends Thread {
+    static final int MAX_THINKING_DURATION_MS = 1000;
+    static final int MAX_EATING_DURATION_MS = 3000;
+    static final int MAX_TAKING_TIME_MS = 1000;
+
+    private final Chopstick left;
+    private final Chopstick right;
+    private final Random random;
+    private int eaten;
+    private final int seat;
+
+    private volatile boolean stop;
+
+    private void log(String message) {
+        synchronized (Philosopher.class) {
+            for (var i = 1; i <= this.seat; i++) {
+                System.out.print("                         ");
+            }
+            System.out.println(threadId() + " " + message);
+        }
+    }
+
+    public void stopPhilosopher() {
+        log("stopping");
+        this.stop = true;
+        interrupt();
+    }
+
+    public Philosopher(int seat, Chopstick left, Chopstick right) {
+        this.stop = false;
+        this.seat = seat;
+        this.left = left;
+        this.right = right;
+        this.random = new Random();
+        this.eaten = 0;
+    }
+
+    @Override
+    public void run() {
+        log("starting");
+        try {
+            while (!this.stop) {
+                think();
+                eat();
+            }
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+        }
+        log("stopped; eaten=" + this.eaten);
+    }
+
+    private void think() throws InterruptedException {
+        Thread.sleep(this.random.nextInt(MAX_THINKING_DURATION_MS));
+    }
+
+    private void eat() throws InterruptedException {
+        log("try taking left");
+        synchronized (this.left) {
+            log("left acquired");
+            Thread.sleep(this.random.nextInt(MAX_TAKING_TIME_MS));
+            log("try taking right");
+            synchronized (this.right) {
+                log("right acquired");
+                log("eating");
+                this.eaten++;
+                Thread.sleep(this.random.nextInt(MAX_EATING_DURATION_MS));
+            }
+            log("right released");
+        }
+        log("left released");
+    }
+}

src/src/PhilosopherExperiment.java

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+public class PhilosopherExperiment {
+
+    static final int PHILOSOPHER_NUM = 3;
+    static final int EXP_DURATION_MS = 20000;
+
+    public static void main(String... args) throws InterruptedException {
+        var chopsticks = new Chopstick[PHILOSOPHER_NUM];
+        var philosophers = new Philosopher[PHILOSOPHER_NUM];
+        for (var i = 0; i < PHILOSOPHER_NUM; i++) {
+            chopsticks[i] = new Chopstick();
+        }
+        for (var i = 0; i < PHILOSOPHER_NUM; i++) {
+            philosophers[i] = new Philosopher(i, chopsticks[i],
+                    chopsticks[(i + 1) % PHILOSOPHER_NUM]);
+        }
+        for (var i = 0; i < PHILOSOPHER_NUM; i++) {
+            philosophers[i].start();
+        }
+        Thread.sleep(EXP_DURATION_MS);
+        for (var i = 0; i < PHILOSOPHER_NUM; i++) {
+            philosophers[i].stopPhilosopher();
+        }
+    }
+}