org.apache.felix.utils.extender

Class AbstractExtender

java.lang.Object

org.apache.felix.utils.extender.AbstractExtender

All Implemented Interfaces:

java.util.EventListener, org.osgi.framework.BundleActivator, org.osgi.framework.BundleListener, org.osgi.framework.SynchronousBundleListener, org.osgi.util.tracker.BundleTrackerCustomizer

public abstract class AbstractExtender
extends java.lang.Object
implements org.osgi.framework.BundleActivator, org.osgi.util.tracker.BundleTrackerCustomizer, org.osgi.framework.SynchronousBundleListener

Base class to write bundle extenders. This extender tracks started bundles (or starting if they have a lazy activation policy) and will create an Extension for each of them to manage it. The extender will handle all concurrency and synchronization issues, see Extension for more information about the additional constraints. The extender guarantee that all extensions will be stopped synchronously with the STOPPING event of a given bundle and that all extensions will be stopped before the extender bundle is stopped.

Constructor Summary

Constructors

Constructor and Description
AbstractExtender()

Method Summary

Methods

Modifier and Type	Method and Description
java.lang.Object	addingBundle(org.osgi.framework.Bundle bundle, org.osgi.framework.BundleEvent event)
void	bundleChanged(org.osgi.framework.BundleEvent event)
protected java.util.Collection<org.osgi.framework.Bundle>	chooseBundlesToDestroy(java.util.Set<org.osgi.framework.Bundle> bundles)
protected java.util.concurrent.ExecutorService	createExecutor() Create the executor used to start extensions asynchronously.
protected abstract void	debug(org.osgi.framework.Bundle bundle, java.lang.String msg)
protected abstract Extension	doCreateExtension(org.osgi.framework.Bundle bundle) Create the extension for the given bundle, or null if the bundle is not to be extended.
protected void	doStart()
protected void	doStop()
protected abstract void	error(java.lang.String msg, java.lang.Throwable t)
org.osgi.framework.BundleContext	getBundleContext()
java.util.concurrent.ExecutorService	getExecutors()
boolean	isPreemptiveShutdown() Check if the extender performs a preemptive shutdown of all extensions when the framework is being stopped.
boolean	isStopping()
boolean	isSynchronous() Check if the extender is synchronous or not.
void	modifiedBundle(org.osgi.framework.Bundle bundle, org.osgi.framework.BundleEvent event, java.lang.Object object)
void	removedBundle(org.osgi.framework.Bundle bundle, org.osgi.framework.BundleEvent event, java.lang.Object object)
void	setPreemptiveShutdown(boolean preemptiveShutdown)
void	setSynchronous(boolean synchronous)
void	start(org.osgi.framework.BundleContext context)
protected void	startTracking()
void	stop(org.osgi.framework.BundleContext context)
protected void	stopTracking()
protected abstract void	warn(org.osgi.framework.Bundle bundle, java.lang.String msg, java.lang.Throwable t)

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractExtender

public AbstractExtender()

Method Detail

isSynchronous

public boolean isSynchronous()

Check if the extender is synchronous or not. If the flag is set, the extender will start the extension synchronously with the bundle being tracked or started. Else, the starting of the extension will be delegated to a thread pool.

Returns:

if the extender is synchronous

isPreemptiveShutdown

public boolean isPreemptiveShutdown()

Check if the extender performs a preemptive shutdown of all extensions when the framework is being stopped. The default behavior is to wait for the framework to stop the bundles and stop the extension at that time.

Returns:

if the extender use a preemptive shutdown

getBundleContext

public org.osgi.framework.BundleContext getBundleContext()

getExecutors

public java.util.concurrent.ExecutorService getExecutors()

setSynchronous

public void setSynchronous(boolean synchronous)

setPreemptiveShutdown

public void setPreemptiveShutdown(boolean preemptiveShutdown)

isStopping

public boolean isStopping()

start

public void start(org.osgi.framework.BundleContext context)
           throws java.lang.Exception

Specified by:

start in interface org.osgi.framework.BundleActivator

Throws:

java.lang.Exception

stop

public void stop(org.osgi.framework.BundleContext context)
          throws java.lang.Exception

Specified by:

stop in interface org.osgi.framework.BundleActivator

Throws:

java.lang.Exception

doStart

protected void doStart()
                throws java.lang.Exception

Throws:

java.lang.Exception

doStop

protected void doStop()
               throws java.lang.Exception

Throws:

java.lang.Exception

startTracking

protected void startTracking()

stopTracking

protected void stopTracking()

createExecutor

protected java.util.concurrent.ExecutorService createExecutor()

Create the executor used to start extensions asynchronously.

Returns:

an

chooseBundlesToDestroy

protected java.util.Collection<org.osgi.framework.Bundle> chooseBundlesToDestroy(java.util.Set<org.osgi.framework.Bundle> bundles)

Parameters:

bundles -

Returns:

bundleChanged

public void bundleChanged(org.osgi.framework.BundleEvent event)

Specified by:

bundleChanged in interface org.osgi.framework.BundleListener

addingBundle

public java.lang.Object addingBundle(org.osgi.framework.Bundle bundle,
                            org.osgi.framework.BundleEvent event)

Specified by:

addingBundle in interface org.osgi.util.tracker.BundleTrackerCustomizer

modifiedBundle

public void modifiedBundle(org.osgi.framework.Bundle bundle,
                  org.osgi.framework.BundleEvent event,
                  java.lang.Object object)

Specified by:

modifiedBundle in interface org.osgi.util.tracker.BundleTrackerCustomizer

removedBundle

public void removedBundle(org.osgi.framework.Bundle bundle,
                 org.osgi.framework.BundleEvent event,
                 java.lang.Object object)

Specified by:

removedBundle in interface org.osgi.util.tracker.BundleTrackerCustomizer

doCreateExtension

protected abstract Extension doCreateExtension(org.osgi.framework.Bundle bundle)
                                        throws java.lang.Exception

Create the extension for the given bundle, or null if the bundle is not to be extended.

Parameters:

bundle - the bundle to extend

Returns:

Throws:

java.lang.Exception

debug

protected abstract void debug(org.osgi.framework.Bundle bundle,
         java.lang.String msg)

warn

protected abstract void warn(org.osgi.framework.Bundle bundle,
        java.lang.String msg,
        java.lang.Throwable t)

error

protected abstract void error(java.lang.String msg,
         java.lang.Throwable t)