Class BarrierSec

java.lang.Object
  BarrierSec

public class BarrierSec
extends Object

This class shows how to synchronice a bunch of people who perform many activities. This implementation is very inefficient because only 1 Bob can work at a time. The main requirement is that no one will be performing activity n+1 until everybody finishes activity n. Each person is called Bob[i].

• The mutex semaphore is used to ensure that only one Bob is performing a task.
• This is not the most efficient solution because a mutex precludes 2 Bobs to be working at the same time on a different activity.
• Semaphore reduce is initialized using the number of Bobs because each Bob[i] needs to signal that they finished all his task before termination.

This is an example of Map/Reduce. In the "Map" face, in programa "main()", the syncrhonization semaphores are set up and the Bob processes are created. The "Reduce" is executed after all the Bob processes are done.

Field Summary

(package private) static int	activity Current activity to be performed by every Bob.
(package private) static int	ManyBobs A bunch of Bobs perform the activities.
(package private) static int	N_Activities This many task will be performed.
(package private) static int	remain Number of Bobs that didnīt finish current activity yet.

Constructor Summary

BarrierSec()

Method Summary

static void

main(String[] args) Main program.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

N_Activities

static final int N_Activities

This many task will be performed.

See Also:

Constant Field Values

activity

static int activity

Current activity to be performed by every Bob.

remain

static int remain

Number of Bobs that didnīt finish current activity yet.

ManyBobs

static final int ManyBobs

A bunch of Bobs perform the activities.

See Also:

Constant Field Values

Constructor Detail

BarrierSec

public BarrierSec()

Method Detail

main

public static void main(String[] args)

Main program.