package org.ph.javaee.training8;
import java.util.concurrent.locks.ReentrantReadWriteLock;
/**
 * A simple thread task representation
 * @author Pierre-Hugues Charbonneau
 *
 */
public class Task {
       // Object used for FLAT lock
       private final Object sharedObject = new Object();
       // ReentrantReadWriteLock used for WRITE & READ locks
       private final ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
       /**
        *  Execution pattern #1
        */
       public void executeTask1() {
             // 1. Attempt to acquire a ReentrantReadWriteLock READ lock
             lock.readLock().lock();
             // Wait 2 seconds to simulate some work...
             try { Thread.sleep(2000);}catch (Throwable any) {}
             try {              
                    // 2. Attempt to acquire a Flat lock...
                    synchronized (sharedObject) {}
             }
             // Remove the READ lock
             finally {
                    lock.readLock().unlock();
             }           
             System.out.println("executeTask1() :: Work Done!");
       }
       /**
        *  Execution pattern #2
        */
       public void executeTask2() {
             // 1. Attempt to acquire a Flat lock
             synchronized (sharedObject) {                 
                    // Wait 2 seconds to simulate some work...
                    try { Thread.sleep(2000);}catch (Throwable any) {}
                    // 2. Attempt to acquire a WRITE lock                   
                    lock.writeLock().lock();
                    try {
                           // Do nothing
                    }
                    // Remove the WRITE lock
                    finally {
                           lock.writeLock().unlock();
                    }
             }
             System.out.println("executeTask2() :: Work Done!");
       }
       public ReentrantReadWriteLock getReentrantReadWriteLock() {
             return lock;
       }
}