org.jclouds.lifecycle

Class BaseLifeCycle

java.lang.Object

org.jclouds.lifecycle.BaseLifeCycle

All Implemented Interfaces:

Runnable, LifeCycle

public abstract class BaseLifeCycle
extends Object
implements Runnable, LifeCycle

// TODO: Adrian: Document this!

Author:

Adrian Cole

Nested Class Summary

Nested classes/interfaces inherited from interface org.jclouds.lifecycle.LifeCycle

LifeCycle.Status

Field Summary

Fields

Modifier and Type	Field and Description
protected List<LifeCycle>	dependencies
protected AtomicReference<Exception>	exception
protected Logger	logger
protected LifeCycle.Status	status
protected Object	statusLock
protected com.google.common.util.concurrent.ListeningExecutorService	userExecutor

Constructor Summary

Constructors

Constructor and Description
BaseLifeCycle(com.google.common.util.concurrent.ListeningExecutorService userExecutor, LifeCycle... dependencies)

Method Summary

Methods

Modifier and Type	Method and Description
void	addDependency(LifeCycle lifeCycle)
protected void	awaitShutdown(long timeout)
protected void	awaitStatus(LifeCycle.Status intended, long timeout)
protected abstract void	doShutdown()
protected abstract void	doWork()
protected void	exceptionIfDependenciesNotActive()
protected void	exceptionIfNotActive()
Exception	getException()
protected Exception	getExceptionFromDependenciesOrNull()
LifeCycle.Status	getStatus()
void	run()
protected boolean	shouldDoWork()
void	shutdown() Requests shutdown of the component.
void	shutdown(long waitMs) Requests shutdown, but will only wait @link waitms milliseconds
void	start() Asynchronously starts the component

Methods inherited from class java.lang.Object

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

Field Detail

logger

protected Logger logger

userExecutor

protected final com.google.common.util.concurrent.ListeningExecutorService userExecutor

dependencies

protected final List<LifeCycle> dependencies

statusLock

protected final Object statusLock

status

protected volatile LifeCycle.Status status

exception

protected AtomicReference<Exception> exception

Constructor Detail

BaseLifeCycle

public BaseLifeCycle(com.google.common.util.concurrent.ListeningExecutorService userExecutor,
             LifeCycle... dependencies)

Method Detail

addDependency

public void addDependency(LifeCycle lifeCycle)

getStatus

public LifeCycle.Status getStatus()

Specified by:

getStatus in interface LifeCycle

Returns:

the current state of the component;

run

public void run()

Specified by:

run in interface Runnable

doWork

protected abstract void doWork()
                        throws Exception

Throws:

Exception

doShutdown

protected abstract void doShutdown()

shouldDoWork

protected boolean shouldDoWork()

Returns:

false if any dependencies are inactive, or we are inactive, or we have a global exception.

start

@PostConstruct
public void start()

Description copied from interface: LifeCycle

Asynchronously starts the component

Specified by:

start in interface LifeCycle

exceptionIfDependenciesNotActive

protected void exceptionIfDependenciesNotActive()

getExceptionFromDependenciesOrNull

protected Exception getExceptionFromDependenciesOrNull()

getException

public Exception getException()

Specified by:

getException in interface LifeCycle

Returns:

Exception or null, if there are no fatal Exceptions encountered in the lifecycle of this component.

awaitShutdown

protected void awaitShutdown(long timeout)
                      throws InterruptedException

Throws:

InterruptedException

awaitStatus

protected void awaitStatus(LifeCycle.Status intended,
               long timeout)
                    throws InterruptedException

Throws:

InterruptedException

shutdown

@PreDestroy
public void shutdown()

Description copied from interface: LifeCycle

Requests shutdown of the component.

Specified by:

shutdown in interface LifeCycle

shutdown

public void shutdown(long waitMs)

Description copied from interface: LifeCycle

Requests shutdown, but will only wait @link waitms milliseconds

Specified by:

shutdown in interface LifeCycle

Parameters:

waitMs - maximum time to wait in milliseconds

exceptionIfNotActive

protected void exceptionIfNotActive()