Dining Philosopher - Last thread not terminating properly

[ttiimmoo]

I wrote this Dining Philosopher code but the last thread does not produce the desired "xxx has finished his dinner" line? What did I do wrong? It seems the last thread terminates prematurely.I would appreciate any help on this.\[code\]import java.util.Random;public class DiningPhilosophers { //An array holding all the chopsticks private final Chopstick[] chopsticks = new Chopstick[5]; /*Constructor for the main class * Creates all the chopsticks * Creates and starts all the threads*/ public DiningPhilosophers(){ putChopsticksOnTheTable(); Thread t1 = new Thread(new Philosopher("First",this.chopsticks[4],this.chopsticks[0])); Thread t2 = new Thread(new Philosopher("Second",this.chopsticks[0],this.chopsticks[1])); Thread t3 = new Thread(new Philosopher("Third",this.chopsticks[1],this.chopsticks[2])); Thread t4 = new Thread(new Philosopher("Fourth",this.chopsticks[2],this.chopsticks[3])); Thread t5 = new Thread(new Philosopher("Fifth",this.chopsticks[3],this.chopsticks[4])); t1.start(); t2.start(); t3.start(); t4.start(); t5.start(); } /*Initialise the chopsticks in the array*/ private void putChopsticksOnTheTable(){ for(int i = 0;i < chopsticks.length;i++) chopsticks= new Chopstick(); } public static void main(String[] args){ new DiningPhilosophers(); }}class Philosopher extends Thread{private static final int EATING_TIME_LIMIT = 1000;private static final int THINKING_TIME_LIMIT = 800;private int EAT_TIMES = 5;private final Random randomise = new Random();private final Chopstick _leftChopstick;private final Chopstick _rightChopstick;private final String _name;private State _state;/* Enumeration class that holds * information about the possible * Philosopher's states */public enum State { EATING, THINKING}/** Main constructor for the Philosopher class* @param name the name of the Philosopher* @param leftChopstick the chopstick that is currently on the left of the Philosopher* @param rightChopstick the chopstick currently on the right of the Philosopher* */public Philosopher(String name, Chopstick leftChopstick, Chopstick rightChopstick) { this._leftChopstick = leftChopstick; this._rightChopstick = rightChopstick; this._name = name;}/** The method eat that uses two chopsticks. It blockes the two Chopstick* objects so they could not be changed then it changes their state * as well as the state of the philosopher* At the end of the method, the chopsticks' state is reverted and* the Philosopher goes into the Thinking state */private void tryToEat() throws InterruptedException { synchronized(_leftChopstick){ while(_leftChopstick.inUse() || _rightChopstick.inUse()) try{ //this.setPhilosopherState(Philosopher.State.WAITING); _leftChopstick.wait(); }catch (InterruptedException e){} synchronized(_rightChopstick) { try{ Thread.sleep(1); _leftChopstick.pickUp(); System.out.println(_name + " picks up the left chopstick..."); _rightChopstick.pickUp(); System.out.println(_name + " picks up the right chopstick..."); eat(); } finally { _leftChopstick.putDown(); System.out.println(_name + " puts down the left chopstick..."); _rightChopstick.putDown(); System.out.println(_name + " puts down the right chopstick..."); //_leftChopstick.notify(); //_rightChopstick.notify(); } } } if(this.EAT_TIMES > 0) think(); }private void eat() throws InterruptedException{ setPhilosopherState(State.EATING); Thread.sleep(randomise.nextInt(EATING_TIME_LIMIT)); this.EAT_TIMES--; if(this.EAT_TIMES == 0) System.out.println("***************************" + _name + " has finished his dinner");}/** This method only changes the state * of the Philosopher to Thinking*/private void think() throws InterruptedException{ setPhilosopherState(Philosopher.State.THINKING); Thread.sleep(randomise.nextInt(THINKING_TIME_LIMIT));}/** Set the current state of the Philosopher*/private void setPhilosopherState(State state){ this._state = state; if(_state == State.EATING) System.out.println ("*** " + _name + " is EATING for the " + (6 - EAT_TIMES) + " time!"); else System.out.println( _name + " is THINKING...");}/** Get the current state of the Philosopher*/public State getPhilosopherState(){ return _state;}/** The method is invoked with the start of the thread* and runs the eat function for 10 times*/public void run(){ while(this.EAT_TIMES > 0){ try { tryToEat(); } catch (InterruptedException e) { e.printStackTrace(); } }} }class Chopstick{ private boolean _inUse; /* * @return the current state of the chopstick */ public boolean inUse(){ return _inUse; } /* * @param usedFlag the new state of the chopstick */ public synchronized void pickUp() { _inUse = true; } public void putDown() { _inUse = false; this.notify(); }}\[/code\]