org.osgi.util.tracker
Interface BundleTrackerCustomizer<T>

Type Parameters:

T - The type of the tracked object.

All Known Implementing Classes:

BundleTracker

public interface BundleTrackerCustomizer<T>

The BundleTrackerCustomizer interface allows a BundleTracker to customize the Bundles that are tracked. A BundleTrackerCustomizer is called when a bundle is being added to a BundleTracker. The BundleTrackerCustomizer can then return an object for the tracked bundle. A BundleTrackerCustomizer is also called when a tracked bundle is modified or has been removed from a BundleTracker.

The methods in this interface may be called as the result of a BundleEvent being received by a BundleTracker. Since BundleEvents are received synchronously by the BundleTracker, it is highly recommended that implementations of these methods do not alter bundle states while being synchronized on any object.

The BundleTracker class is thread-safe. It does not call a BundleTrackerCustomizer while holding any locks. BundleTrackerCustomizer implementations must also be thread-safe.

Since:

1.4

ThreadSafe

Method Summary

T	addingBundle(Bundle bundle, BundleEvent event) A bundle is being added to the BundleTracker.
void	modifiedBundle(Bundle bundle, BundleEvent event, T object) A bundle tracked by the BundleTracker has been modified.
void	removedBundle(Bundle bundle, BundleEvent event, T object) A bundle tracked by the BundleTracker has been removed.

Method Detail

addingBundle

T addingBundle(Bundle bundle,
               BundleEvent event)

A bundle is being added to the BundleTracker.

This method is called before a bundle which matched the search parameters of the BundleTracker is added to the BundleTracker. This method should return the object to be tracked for the specified Bundle. The returned object is stored in the BundleTracker and is available from the getObject method.

Parameters:

bundle - The Bundle being added to the BundleTracker .

event - The bundle event which caused this customizer method to be called or null if there is no bundle event associated with the call to this method.

Returns:

The object to be tracked for the specified Bundle object or null if the specified Bundle object should not be tracked.

modifiedBundle

void modifiedBundle(Bundle bundle,
                    BundleEvent event,
                    T object)

A bundle tracked by the BundleTracker has been modified.

This method is called when a bundle being tracked by the BundleTracker has had its state modified.

Parameters:

bundle - The Bundle whose state has been modified.

event - The bundle event which caused this customizer method to be called or null if there is no bundle event associated with the call to this method.

object - The tracked object for the specified bundle.

removedBundle

void removedBundle(Bundle bundle,
                   BundleEvent event,
                   T object)

A bundle tracked by the BundleTracker has been removed.

This method is called after a bundle is no longer being tracked by the BundleTracker.

Parameters:

bundle - The Bundle that has been removed.

event - The bundle event which caused this customizer method to be called or null if there is no bundle event associated with the call to this method.

object - The tracked object for the specified bundle.