org.opensaml.util.resource
Class ResourceChangeWatcher

java.lang.Object
  java.util.TimerTask
      org.opensaml.util.resource.ResourceChangeWatcher

All Implemented Interfaces:

Runnable

public class ResourceChangeWatcher
extends TimerTask

A watcher that invokes a callback when a resource update/deletion has been detected.

Field Summary

static int	DEFAULT_MAX_RETRY_ATTEMPTS Default maximum retry attempts, 0.
static long	DEFAULT_POLL_FREQUENCY Default polling frequency, 12 hours.

Constructor Summary

ResourceChangeWatcher(Resource resource)
Constructor.

ResourceChangeWatcher(Resource resource, long pollingFrequency)
Constructor.

ResourceChangeWatcher(Resource resource, long pollingFrequency, int retryAttempts)
Constructor.

Method Summary

long	getPollingFrequency() Gets the frequency, in milliseconds, the watched resource should be polled.
List<ResourceChangeListener>	getResourceListeners() Gets the list of registered resource listeners.
void	run()
protected void	signalListeners(ResourceChangeListener.ResourceChange changeType) Signals all registered listeners of a resource change.

Methods inherited from class java.util.TimerTask

cancel, scheduledExecutionTime

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_POLL_FREQUENCY

public static final long DEFAULT_POLL_FREQUENCY

Default polling frequency, 12 hours.

See Also:

Constant Field Values

DEFAULT_MAX_RETRY_ATTEMPTS

public static final int DEFAULT_MAX_RETRY_ATTEMPTS

Default maximum retry attempts, 0.

See Also:

Constant Field Values

Constructor Detail

ResourceChangeWatcher

public ResourceChangeWatcher(Resource resource)
                      throws ResourceException

Constructor.

Parameters:

resource - the resource to be watched

Throws:

ResourceException - thrown if resource existence or last modification time can not be determined

ResourceChangeWatcher

public ResourceChangeWatcher(Resource resource,
                             long pollingFrequency)
                      throws ResourceException

Constructor.

Parameters:

resource - the resource to be watched

pollingFrequency - the frequency, in milliseconds, to poll the resource for changes

Throws:

ResourceException - thrown if resource existence or last modification time can not be determined

ResourceChangeWatcher

public ResourceChangeWatcher(Resource resource,
                             long pollingFrequency,
                             int retryAttempts)
                      throws ResourceException

Constructor.

Parameters:

resource - the resource to be watched

pollingFrequency - the frequency, in milliseconds, to poll the resource for changes

retryAttempts - maximum number of poll attempts before the resource is considered inaccessible

Throws:

ResourceException - thrown if resource existence or last modification time can not be determined

Method Detail

getPollingFrequency

public long getPollingFrequency()

Gets the frequency, in milliseconds, the watched resource should be polled.

Returns:

frequency the watched resource should be polled

getResourceListeners

public List<ResourceChangeListener> getResourceListeners()

Gets the list of registered resource listeners. New listeners may be registered with the list or old ones removed.

Returns:

list of registered resource listeners

run

public void run()

Specified by:

run in interface Runnable

Specified by:

run in class TimerTask

signalListeners

protected void signalListeners(ResourceChangeListener.ResourceChange changeType)

Signals all registered listeners of a resource change.

Parameters:

changeType - the resource change type