Baskov_S_K_synchronizer

src/main/java/hse/java/lectures/lecture6/tasks/synchronizer/StreamWriter.java

@@ -28,9 +28,11 @@ public void attachMonitor(StreamingMonitor monitor) {
     public void run() {
         // Writer threads are intentionally infinite for the task contract.
         while (true) {
-            output.print(message);
-            onTick.run();
+            try {
+                monitor.tick(id, onTick, output, message);
+            } catch (InterruptedException e) {
+                throw new RuntimeException(e);
+            }
         }
     }
-
 }

src/main/java/hse/java/lectures/lecture6/tasks/synchronizer/StreamingMonitor.java

@@ -1,5 +1,43 @@
 package hse.java.lectures.lecture6.tasks.synchronizer;
 
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.With;
+
+import java.io.PrintStream;
+
+@Getter
 public class StreamingMonitor {
     // impl your sync here
-}
+    private final Object key = new Object();
+    private final int N;
+    private final int ticksPerWriter;
+    private int cnt = 0;
+    private int nowId = 1;
+
+    public StreamingMonitor(int size, int ticksPerWriter) {
+        this.N = size;
+        this.ticksPerWriter = size * ticksPerWriter;
+    }
+
+    public synchronized void check() throws InterruptedException {
+        while(cnt < ticksPerWriter){
+            wait();
+        }
+    }
+
+    public synchronized void tick(int idCome, Runnable onTick, PrintStream output, String message) throws InterruptedException {
+
+        while (idCome != nowId || cnt >= ticksPerWriter) {
+            wait();
+        }
+
+        nowId = Integer.max(1, (nowId + 1) % (N+1));
+        cnt += 1;
+
+        output.print(message);
+        onTick.run();
+
+        notifyAll();
+    }
+}

src/main/java/hse/java/lectures/lecture6/tasks/synchronizer/Synchronizer.java

@@ -1,5 +1,6 @@
 package hse.java.lectures.lecture6.tasks.synchronizer;
 
+import javax.management.monitor.Monitor;
 import java.util.List;
 
 public class Synchronizer {
@@ -22,12 +23,25 @@ public Synchronizer(List<StreamWriter> tasks, int ticksPerWriter) {
      * in strict ascending id order.
      */
     public void execute() {
-        // add monitor and sync
+        StreamingMonitor streamingMonitor = new StreamingMonitor(tasks.size(), ticksPerWriter);
+
+        for (var stream : tasks){
+            stream.attachMonitor(streamingMonitor);
+        }
+
         for (StreamWriter writer : tasks) {
             Thread worker = new Thread(writer, "stream-writer-" + writer.getId());
             worker.setDaemon(true);
             worker.start();
         }
+
+        try {
+            streamingMonitor.check();
+        } catch (InterruptedException e) {
+            throw new RuntimeException(e);
+        }
+
+
     }
 
-}
+}