pt.ua.concurrent
Class DynamicBarrier

java.lang.Object
  pt.ua.concurrent.CObject
      pt.ua.concurrent.DynamicBarrier

All Implemented Interfaces:

Barrier, InterruptibleAwaitingThreads, SyncCV

public class DynamicBarrier
extends CObject
implements Barrier

A dynamically sized thread barrier class.

This class follows DbC(tm) methodology (Wikipedia). Where possible, contracts are implement with native's Java assert.

Version:

0.5, October 2013

Author:

Miguel Oliveira e Silva (mos@ua.pt)

Constructor Summary

DynamicBarrier()
Constructs a new dynamic barrier registering waiting threads.

DynamicBarrier(boolean registerAwaitingThreads)
Constructs a new dynamic barrier.

Method Summary

void	await() Caller will wait until all signed barrier threads are also waiting, situation in which all of them are awakened.
boolean	isSignIn() Is current thread registered in barrier?
int	numberWaitingThreads() Number of threads currently waiting on the barrier.
void	signIn() Add signature of current thread in the barrier.
void	signOut() Remove signature of current thread in the barrier.
int	size() Number of threads defined for the barrier.

Methods inherited from class pt.ua.concurrent.CObject

await, await, broadcast, interruptWaitingThreads, lockIsMine, registerAwaitingThreads, signal, syncronizedLockIsMine

Methods inherited from class java.lang.Object

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

Constructor Detail

DynamicBarrier

public DynamicBarrier()

Constructs a new dynamic barrier registering waiting threads.

DynamicBarrier

public DynamicBarrier(boolean registerAwaitingThreads)

Constructs a new dynamic barrier.

Parameters:

registerAwaitingThreads - if true, threads are registered when waiting

Method Detail

isSignIn

public boolean isSignIn()

Is current thread registered in barrier?

Returns:

true, if thread is registered; false otherwise

signIn

public void signIn()

Add signature of current thread in the barrier.

Precondition:

!isSignIn()

Postcondition:

isSignIn()

signOut

public void signOut()

Remove signature of current thread in the barrier.

Precondition:

isSignIn()

Postcondition:

!isSignIn()

size

public int size()

Description copied from interface: Barrier

Number of threads defined for the barrier.

Specified by:

size in interface Barrier

Returns:

barrier size

numberWaitingThreads

public int numberWaitingThreads()

Description copied from interface: Barrier

Number of threads currently waiting on the barrier.

Specified by:

numberWaitingThreads in interface Barrier

Returns:

number of threads

await

public void await()
           throws ThreadInterruptedException

Caller will wait until all signed barrier threads are also waiting, situation in which all of them are awakened.

Precondition:

isSignIn()

Specified by:

await in interface Barrier

Specified by:

await in interface SyncCV

Overrides:

await in class CObject

Throws:

ThreadInterruptedException