org.jboss.as.ee.component.deployers

Class StartupCountdown

java.lang.Object

org.jboss.as.ee.component.deployers.StartupCountdown

public final class StartupCountdown
extends Object

Countdown tracker with capabilities similar to SE CountDownLatch, but allowing threads to mark and unmark themselves as privileged. Privileged threads, when entering await method, will immediately proceed without checking latch's state. This reentrant behaviour allows to work around situations where there is a possibility of a deadlock.

Author:

Fedor Gavrilov

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	StartupCountdown.Frame

Constructor Summary

Constructors

Constructor and Description
StartupCountdown(int count)

Method Summary

Modifier and Type	Method and Description
void	addCallback(Runnable callback) Executes a lightweight action when the countdown reaches 0.
void	await()
void	countDown()
void	countUp(int count)
static StartupCountdown.Frame	current()
StartupCountdown.Frame	enter()
boolean	isPrivileged()
static void	restore(StartupCountdown.Frame frame)

Methods inherited from class java.lang.Object

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

Constructor Detail

StartupCountdown

public StartupCountdown(int count)

Method Detail

countDown

public void countDown()

countUp

public void countUp(int count)

await

public void await()
           throws InterruptedException

Throws:

InterruptedException

addCallback

public void addCallback(Runnable callback)

Executes a lightweight action when the countdown reaches 0. If StartupCountdown is not at zero when the method is called, passed callback will be executed by the last thread to call countDown. If StartupCountdown is at zero already, passed callback will be executed immediately by the caller thread.

Parameters:

callback - to execute. Should not be null.

isPrivileged

public boolean isPrivileged()

enter

public StartupCountdown.Frame enter()

current

public static StartupCountdown.Frame current()

restore

public static void restore(StartupCountdown.Frame frame)