Make two threads with mutex type D running

ta1/Main.java

@@ -6,7 +6,13 @@ class Main {
 		// Create different mutex
 		Mutex mutD = new MutexTypeD();
 
+		Task t0 = new Task("T0", 0, mutD);
 		Task t1 = new Task("T1", 1, mutD);
+
+		t0.describe();
 		t1.describe();
+
+		t0.start();
+		t1.start();
 	}
 }  

ta1/Mutex.java

@@ -1,3 +1,27 @@
 
 public abstract class Mutex {
+
+	public static void criticalSection() {
+		try {
+			Thread.sleep((int) (Math.random() * 3000));
+		}
+		catch (InterruptedException e) {
+			// Nothing
+		}
+	}
+
+	public static void nonCriticalSection() {
+		try {
+			Thread.sleep((int) (Math.random() * 3000));
+		}
+		catch (InterruptedException e) {
+			// Nothing
+		}
+	}
+
+	// Take ownership
+	public abstract void p(int id);
+
+	// Release ownership
+	public abstract void v(int id);
 }

ta1/MutexTypeD.java

@@ -1,7 +1,32 @@
 
 class MutexTypeD extends Mutex {
+
+	private volatile int turn;
+	private volatile boolean[] flag;
 	
 	MutexTypeD() {
+		turn = 0;
+
+		flag = new boolean[2];
+		flag[0] = flag[1] = false;
+	}
+
+	public void p(int id) {
+		int other = 1 - id;
+		flag[id] = true;
+
+		while (flag[other] == true) {
+			if (turn == other) {
+				flag[id] = false;
+				while (turn == other) Thread.yield();
+				flag[id] = true;
+			}
+		}
+	}
+
+	public void v(int id) {
+		turn = 1 - id;
+		flag[id] = false;
 	}
 
 	public String toString() {

ta1/Task.java

@@ -14,4 +14,18 @@ class Task extends Thread {
 	public void describe() {
 		System.out.println(id + "<" + critical + ">:" + name);
 	}
+
+	public void run() {
+		while (true) {
+			critical.p(id);
+
+			System.out.println( name + " is CRITICAL!");
+			Mutex.criticalSection();
+
+			critical.v(id);
+
+			System.out.println( name + " non critical.");
+			Mutex.nonCriticalSection();
+		}
+	}
 }