6.1 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Module 6: Process Synchronization Codes

6.2 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Example I Design a producer consumer problem with single buffer

6.3 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Producer

6.4 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Consumer

6.5 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Tester Class

6.6 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Example 2 (without separate classes) import java.util.Random; public class ProducerConsumerProblem { public static void main(String[] args) { final Buffer buffer = new Buffer(); // buffer // producer thread Thread producer = new Thread(new Runnable() { public void run() { Random r = new Random(); for (int i = 0; i < 10; i++) { try { int x = r.nextInt(100-2) + 2; buffer.put(x); } catch (InterruptedException e) { e.printStackTrace(); } }); // consumer thread Thread consumer = new Thread(new Runnable() { public void run() { for (int i = 0; i < 10; i++) { try { buffer.get(); } catch (InterruptedException e) { e.printStackTrace(); } });

6.7 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Bounded Buffer Problem (buffer as stack)

6.8 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Tester Code

6.9 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Semaphore (mutex) import java.util.concurrent.Semaphore; //library public class SemaphoreTest { Semaphore binary = new Semaphore(1); public static void main(String args[]) { final SemaphoreTest test = new SemaphoreTest(); new public void run(){ test.mutualExclusion(); } }.start(); new public void run(){ test.mutualExclusion(); } }.start(); }

6.10 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Counting Semaphore It will take more than two values

6.11 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Semaphore methods Notify and notifyAll()

6.12 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Process class

6.13 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Tester

6.14 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Semaphores

6.15 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Monitors

6.16 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Monitors (Contd…)

6.17 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Monitor Class

6.18 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition Output

6.19 Silberschatz, Galvin and Gagne ©2009 Operating System Concepts with Java – 8 th Edition