org.ow2.chameleon.core.activators

Class DirectoryMonitor

java.lang.Object

org.ow2.chameleon.core.activators.DirectoryMonitor

All Implemented Interfaces:

org.osgi.framework.BundleActivator, org.osgi.util.tracker.ServiceTrackerCustomizer<Deployer,Deployer>, Watcher

public class DirectoryMonitor
extends Object
implements org.osgi.framework.BundleActivator, Watcher, org.osgi.util.tracker.ServiceTrackerCustomizer<Deployer,Deployer>

Monitors a directory. It tracks all deployer services exposed in the framework and delegate the file events to the adequate deployer.

Version:

$Id: 1.0.4 $Id

Author:

The OW2 Chameleon Team

Field Summary

Fields

Modifier and Type	Field and Description
protected List<Deployer>	deployers List of deployers.

Constructor Summary

Constructors

Constructor and Description
DirectoryMonitor()

Method Summary

Modifier and Type	Method and Description
boolean	acquireReadLockIfNotHeld() Acquires the read lock only and only if no read lock is already held by the current thread.
boolean	acquireWriteLockIfNotHeld() Acquires the write lock only and only if the write lock is not already held by the current thread.
boolean	add(File directory, boolean watch) Adds a directory to the watcher.
boolean	add(File directory, long polling) Adds a directory to the watcher.
Deployer	addingService(org.osgi.framework.ServiceReference<Deployer> reference)
void	modifiedService(org.osgi.framework.ServiceReference<Deployer> reference, Deployer o)
boolean	releaseReadLockIfHeld() Releases the read lock only and only if the read lock is held by the current thread.
boolean	releaseWriteLockIfHeld() Releases the write lock only and only if the write lock is held by the current thread.
boolean	removeAndStopIfNeeded(File directory) If the directory was added, remove it.
void	removedService(org.osgi.framework.ServiceReference<Deployer> reference, Deployer deployer)
void	start(org.osgi.framework.BundleContext context)
void	stop(org.osgi.framework.BundleContext context)

Methods inherited from class java.lang.Object

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

Field Detail

deployers

protected final List<Deployer> deployers

List of deployers.

Constructor Detail

DirectoryMonitor

public DirectoryMonitor()

Method Detail

acquireWriteLockIfNotHeld

public boolean acquireWriteLockIfNotHeld()

Acquires the write lock only and only if the write lock is not already held by the current thread.

Returns:

true if the lock was acquired within the method, false otherwise.

releaseWriteLockIfHeld

public boolean releaseWriteLockIfHeld()

Releases the write lock only and only if the write lock is held by the current thread.

Returns:

true if the lock has no more holders, false otherwise.

acquireReadLockIfNotHeld

public boolean acquireReadLockIfNotHeld()

Acquires the read lock only and only if no read lock is already held by the current thread.

Returns:

true if the lock was acquired within the method, false otherwise.

releaseReadLockIfHeld

public boolean releaseReadLockIfHeld()

Releases the read lock only and only if the read lock is held by the current thread.

Returns:

true if the lock has no more holders, false otherwise.

start

public void start(org.osgi.framework.BundleContext context)
           throws IOException

Specified by:

start in interface org.osgi.framework.BundleActivator

Throws:

IOException

stop

public void stop(org.osgi.framework.BundleContext context)

Specified by:

stop in interface org.osgi.framework.BundleActivator

addingService

public Deployer addingService(org.osgi.framework.ServiceReference<Deployer> reference)

Specified by:

addingService in interface org.osgi.util.tracker.ServiceTrackerCustomizer<Deployer,Deployer>

modifiedService

public void modifiedService(org.osgi.framework.ServiceReference<Deployer> reference,
                            Deployer o)

Specified by:

modifiedService in interface org.osgi.util.tracker.ServiceTrackerCustomizer<Deployer,Deployer>

removedService

public void removedService(org.osgi.framework.ServiceReference<Deployer> reference,
                           Deployer deployer)

Specified by:

removedService in interface org.osgi.util.tracker.ServiceTrackerCustomizer<Deployer,Deployer>

add

public boolean add(File directory,
                   boolean watch)

Adds a directory to the watcher. If `watch` is true, the directory is monitored, otherwise only the initial provisioning is done.

Adds a directory to the watcher. If `watch` is true, the directory is monitored, otherwise only the initial provisioning is done.

Specified by:

add in interface Watcher

Parameters:

directory - the directory

watch - true to enable the watch mode.

Returns:

true if the directory was added, false otherwise.

add

public boolean add(File directory,
                   long polling)

Adds a directory to the watcher. If `polling` is not -1, the directory is monitored, otherwise only the initial provisioning is done.

Adds a directory to the watcher. If `polling` is not -1, the directory is monitored, otherwise only the initial provisioning is done.

Specified by:

add in interface Watcher

Parameters:

directory - the directory

polling - the polling period in ms, -1 to disable the watch.

Returns:

true if the directory was added, false otherwise.

removeAndStopIfNeeded

public boolean removeAndStopIfNeeded(File directory)

If the directory was added, remove it. It the monitoring was enable it disable the monitoring. You have to call stop on all directories where the add methods have returned true.

If the directory is watched, stop it.

Specified by:

removeAndStopIfNeeded in interface Watcher

Parameters:

directory - the directory

Returns:

true if the directory was watched and stopped.