Modifier and Type	Class and Description
private class	ServiceTracker.AllTracked Subclass of Tracked which implements the AllServiceListener interface.
private class	ServiceTracker.Tracked Inner class which subclasses AbstractTracked.

Modifier and Type	Field and Description
private volatile ServiceReference<S>	cachedReference Cached ServiceReference for getServiceReference.
private volatile T	cachedService Cached service object for getService.
protected final BundleContext	context The Bundle Context used by this `ServiceTracker`.
pack-priv final ServiceTrackerCustomizer<S, T>	customizer The `ServiceTrackerCustomizer` for this tracker.
pack-priv static final boolean	DEBUG
protected final Filter	filter The Filter used by this `ServiceTracker` which specifies the search criteria for the services to track.
pack-priv final String	listenerFilter Filter string for use when adding the ServiceListener.
private final String	trackClass Class name to be tracked.
private volatile ServiceTracker<S, T>.Tracked	tracked Tracked services: `ServiceReference` -> customized Object and `ServiceListener` object
private final ServiceReference<S>	trackReference Reference to be tracked.

Constructor Summary

Access	Constructor and Description
public	ServiceTracker(final BundleContext The `BundleContext` against which the tracking is done. context, final ServiceReference<S> The `ServiceReference` for the service to be tracked. reference, final ServiceTrackerCustomizer<S, T> The customizer object to call when services are added, modified, or removed in this `ServiceTracker`. If customizer is `null`, then this `ServiceTracker` will be used as the `ServiceTrackerCustomizer` and this `ServiceTracker` will call the `ServiceTrackerCustomizer` methods on itself. customizer) Create a `ServiceTracker` on the specified `ServiceReference` .
public	ServiceTracker(final BundleContext The `BundleContext` against which the tracking is done. context, final String The class name of the services to be tracked. clazz, final ServiceTrackerCustomizer<S, T> The customizer object to call when services are added, modified, or removed in this `ServiceTracker`. If customizer is `null`, then this `ServiceTracker` will be used as the `ServiceTrackerCustomizer` and this `ServiceTracker` will call the `ServiceTrackerCustomizer` methods on itself. customizer) Create a `ServiceTracker` on the specified class name.
public	ServiceTracker(final BundleContext The `BundleContext` against which the tracking is done. context, final Filter The `Filter` to select the services to be tracked. filter, final ServiceTrackerCustomizer<S, T> The customizer object to call when services are added, modified, or removed in this `ServiceTracker`. If customizer is null, then this `ServiceTracker` will be used as the `ServiceTrackerCustomizer` and this `ServiceTracker` will call the `ServiceTrackerCustomizer` methods on itself. customizer) Create a `ServiceTracker` on the specified `Filter` object.
public	ServiceTracker(final BundleContext The `BundleContext` against which the tracking is done. context, final Class<S> The class of the services to be tracked. clazz, final ServiceTrackerCustomizer<S, T> The customizer object to call when services are added, modified, or removed in this `ServiceTracker`. If customizer is `null`, then this `ServiceTracker` will be used as the `ServiceTrackerCustomizer` and this `ServiceTracker` will call the `ServiceTrackerCustomizer` methods on itself. customizer) Create a `ServiceTracker` on the specified class.

Method Summary

Modifier and Type	Method and Description
public T	Returns: The service object to be tracked for the service added to this `ServiceTracker`. addingService(ServiceReference<S> The reference to the service being added to this `ServiceTracker`. reference) Implements org.osgi.util.tracker.ServiceTrackerCustomizer.addingService. Default implementation of the `ServiceTrackerCustomizer.addingService` method.
public void	close() Close this `ServiceTracker`.
private ServiceReference<S>[]	Returns: The list of initial `ServiceReference`s. getInitialReferences(boolean If `true`, use `getAllServiceReferences`. trackAllServices, String The class name with which the service was registered, or `null` for all services. className, String The filter criteria or `null` for all services. filterString) Returns the list of initial `ServiceReference`s that will be tracked by this `ServiceTracker`.
public T	Returns: A service object or `null` if the service referenced by the specified `ServiceReference` is not being tracked. getService(ServiceReference<S> The reference to the desired service. reference) Returns the service object for the specified `ServiceReference` if the specified referenced service is being tracked by this `ServiceTracker`.
public T	Returns: A service object or `null` if no services are being tracked. getService() Returns a service object for one of the services being tracked by this `ServiceTracker`.
public ServiceReference<S>	Returns: A `ServiceReference` or `null` if no services are being tracked. getServiceReference() Returns a `ServiceReference` for one of the services being tracked by this `ServiceTracker`.
public ServiceReference<S>[]	Returns: Array of `ServiceReference`s or `null` if no services are being tracked. getServiceReferences() Return an array of `ServiceReference`s for all services being tracked by this `ServiceTracker`.
public Object[]	Returns: An array of service objects or `null` if no services are being tracked. getServices() Return an array of service objects for all services being tracked by this `ServiceTracker`.
public T[]	Returns: An array of service objects being tracked. If the specified array is large enough to hold the result, then the specified array is returned. If the specified array is longer then necessary to hold the result, the array element after the last service object is set to `null`. If the specified array is not large enough to hold the result, a new array is created and returned. getServices(T[] An array into which the tracked service objects will be stored, if the array is large enough. array) Return an array of service objects for all services being tracked by this `ServiceTracker`.
public SortedMap<ServiceReference<S>, T>	Returns: A `SortedMap` with the `ServiceReference`s and service objects for all services being tracked by this `ServiceTracker`. If no services are being tracked, then the returned map is empty. getTracked() Return a `SortedMap` of the `ServiceReference`s and service objects for all services being tracked by this `ServiceTracker`.
public int	Returns: The tracking count for this `ServiceTracker` or -1 if this `ServiceTracker` is not open. getTrackingCount() Returns the tracking count for this `ServiceTracker`.
public boolean	Returns: `true` if this `ServiceTracker` is not tracking any services. isEmpty() Return if this `ServiceTracker` is empty.
pack-priv void	modified() Called by the Tracked object whenever the set of tracked services is modified.
public void	modifiedService(ServiceReference<S> The reference to modified service. reference, T The service object for the modified service. service) Implements org.osgi.util.tracker.ServiceTrackerCustomizer.modifiedService. Default implementation of the `ServiceTrackerCustomizer.modifiedService` method.
public void	open() Open this `ServiceTracker` and begin tracking services.
public void	open(boolean If `true`, then this `ServiceTracker` will track all matching services regardless of class loader accessibility. If `false`, then this `ServiceTracker` will only track matching services which are class loader accessible to the bundle whose `BundleContext` is used by this `ServiceTracker`. trackAllServices) Open this `ServiceTracker` and begin tracking services.
public void	remove(ServiceReference<S> The reference to the service to be removed. reference) Remove a service from this `ServiceTracker`.
public void	removedService(ServiceReference<S> The reference to removed service. reference, T The service object for the removed service. service) Implements org.osgi.util.tracker.ServiceTrackerCustomizer.removedService. Default implementation of the `ServiceTrackerCustomizer.removedService` method.
public int	Returns: The number of services being tracked. size() Return the number of services being tracked by this `ServiceTracker`.
private ServiceTracker<S, T>.Tracked	Returns: The current Tracked object. tracked() Accessor method for the current Tracked object.
public T	Returns: Returns the result of `getService()`. waitForService(long The time interval in milliseconds to wait. If zero, the method will wait indefinitely. timeout) Wait for at least one service to be tracked by this `ServiceTracker`.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

Field Detail

cachedReference	back to summary
private volatile ServiceReference<S> cachedReference Cached ServiceReference for getServiceReference. This field is volatile since it is accessed by multiple threads.

cachedService	back to summary
private volatile T cachedService Cached service object for getService. This field is volatile since it is accessed by multiple threads.

context	back to summary
protected final BundleContext context The Bundle Context used by this `ServiceTracker`.

customizer	back to summary
pack-priv final ServiceTrackerCustomizer<S, T> customizer The `ServiceTrackerCustomizer` for this tracker.

DEBUG	back to summary
pack-priv static final boolean DEBUG

filter back to summary

filter	back to summary
protected final Filter filter The Filter used by this `ServiceTracker` which specifies the search criteria for the services to track. Since 1.1

protected final Filter filter

The Filter used by this ServiceTracker which specifies the search criteria for the services to track.

Since: 1.1

listenerFilter	back to summary
pack-priv final String listenerFilter Filter string for use when adding the ServiceListener. If this field is set, then certain optimizations can be taken since we don't have a user supplied filter.

trackClass	back to summary
private final String trackClass Class name to be tracked. If this field is set, then we are tracking by class name.

tracked	back to summary
private volatile ServiceTracker<S, T>.Tracked tracked Tracked services: `ServiceReference` -> customized Object and `ServiceListener` object

trackReference	back to summary
private final ServiceReference<S> trackReference Reference to be tracked. If this field is set, then we are tracking a single ServiceReference.

Constructor Detail

ServiceTracker back to summary

ServiceTracker	back to summary
public ServiceTracker(final BundleContext context, final ServiceReference<S> reference, final ServiceTrackerCustomizer<S, T> customizer) Create a `ServiceTracker` on the specified `ServiceReference` . The service referenced by the specified `ServiceReference` will be tracked by this `ServiceTracker`. Parameters context:BundleContext The `BundleContext` against which the tracking is done. reference:ServiceReference<S> The `ServiceReference` for the service to be tracked. customizer:ServiceTrackerCustomizer<S, T> The customizer object to call when services are added, modified, or removed in this `ServiceTracker`. If customizer is `null`, then this `ServiceTracker` will be used as the `ServiceTrackerCustomizer` and this `ServiceTracker` will call the `ServiceTrackerCustomizer` methods on itself.

public ServiceTracker(final BundleContext context, final ServiceReference<S> reference, final ServiceTrackerCustomizer<S, T> customizer)

Create a ServiceTracker on the specified ServiceReference .

The service referenced by the specified ServiceReference will be tracked by this ServiceTracker.

Parameters

context:BundleContext: The BundleContext against which the tracking is done.
reference:ServiceReference<S>: The ServiceReference for the service to be tracked.
customizer:ServiceTrackerCustomizer<S, T>: The customizer object to call when services are added, modified, or removed in this ServiceTracker. If customizer is null, then this ServiceTracker will be used as the ServiceTrackerCustomizer and this ServiceTracker will call the ServiceTrackerCustomizer methods on itself.

ServiceTracker back to summary

ServiceTracker	back to summary
public ServiceTracker(final BundleContext context, final String clazz, final ServiceTrackerCustomizer<S, T> customizer) Create a `ServiceTracker` on the specified class name. Services registered under the specified class name will be tracked by this `ServiceTracker`. Parameters context:BundleContext The `BundleContext` against which the tracking is done. clazz:String The class name of the services to be tracked. customizer:ServiceTrackerCustomizer<S, T> The customizer object to call when services are added, modified, or removed in this `ServiceTracker`. If customizer is `null`, then this `ServiceTracker` will be used as the `ServiceTrackerCustomizer` and this `ServiceTracker` will call the `ServiceTrackerCustomizer` methods on itself.

public ServiceTracker(final BundleContext context, final String clazz, final ServiceTrackerCustomizer<S, T> customizer)

Create a ServiceTracker on the specified class name.

Services registered under the specified class name will be tracked by this ServiceTracker.

Parameters

context:BundleContext: The BundleContext against which the tracking is done.
clazz:String: The class name of the services to be tracked.
customizer:ServiceTrackerCustomizer<S, T>: The customizer object to call when services are added, modified, or removed in this ServiceTracker. If customizer is null, then this ServiceTracker will be used as the ServiceTrackerCustomizer and this ServiceTracker will call the ServiceTrackerCustomizer methods on itself.

ServiceTracker back to summary

ServiceTracker	back to summary
public ServiceTracker(final BundleContext context, final Filter filter, final ServiceTrackerCustomizer<S, T> customizer) Create a `ServiceTracker` on the specified `Filter` object. Services which match the specified `Filter` object will be tracked by this `ServiceTracker`. Parameters context:BundleContext The `BundleContext` against which the tracking is done. filter:Filter The `Filter` to select the services to be tracked. customizer:ServiceTrackerCustomizer<S, T> The customizer object to call when services are added, modified, or removed in this `ServiceTracker`. If customizer is null, then this `ServiceTracker` will be used as the `ServiceTrackerCustomizer` and this `ServiceTracker` will call the `ServiceTrackerCustomizer` methods on itself. Since 1.1

public ServiceTracker(final BundleContext context, final Filter filter, final ServiceTrackerCustomizer<S, T> customizer)

Create a ServiceTracker on the specified Filter object.

Services which match the specified Filter object will be tracked by this ServiceTracker.

Parameters

context:BundleContext: The BundleContext against which the tracking is done.
filter:Filter: The Filter to select the services to be tracked.
customizer:ServiceTrackerCustomizer<S, T>: The customizer object to call when services are added, modified, or removed in this ServiceTracker. If customizer is null, then this ServiceTracker will be used as the ServiceTrackerCustomizer and this ServiceTracker will call the ServiceTrackerCustomizer methods on itself.

Since

1.1

ServiceTracker back to summary

ServiceTracker	back to summary
public ServiceTracker(final BundleContext context, final Class<S> clazz, final ServiceTrackerCustomizer<S, T> customizer) Create a `ServiceTracker` on the specified class. Services registered under the name of the specified class will be tracked by this `ServiceTracker`. Parameters context:BundleContext The `BundleContext` against which the tracking is done. clazz:Class<S> The class of the services to be tracked. customizer:ServiceTrackerCustomizer<S, T> The customizer object to call when services are added, modified, or removed in this `ServiceTracker`. If customizer is `null`, then this `ServiceTracker` will be used as the `ServiceTrackerCustomizer` and this `ServiceTracker` will call the `ServiceTrackerCustomizer` methods on itself. Since 1.5

public ServiceTracker(final BundleContext context, final Class<S> clazz, final ServiceTrackerCustomizer<S, T> customizer)

Create a ServiceTracker on the specified class.

Services registered under the name of the specified class will be tracked by this ServiceTracker.

Parameters

context:BundleContext: The BundleContext against which the tracking is done.
clazz:Class<S>: The class of the services to be tracked.
customizer:ServiceTrackerCustomizer<S, T>: The customizer object to call when services are added, modified, or removed in this ServiceTracker. If customizer is null, then this ServiceTracker will be used as the ServiceTrackerCustomizer and this ServiceTracker will call the ServiceTrackerCustomizer methods on itself.

Since

1.5

Method Detail

addingService back to summary

addingService	back to summary
public T addingService(ServiceReference<S> reference) Implements org.osgi.util.tracker.ServiceTrackerCustomizer.addingService. Default implementation of the `ServiceTrackerCustomizer.addingService` method. This method is only called when this `ServiceTracker` has been constructed with a `null ServiceTrackerCustomizer` argument. This implementation returns the result of calling `getService` on the `BundleContext` with which this `ServiceTracker` was created passing the specified `ServiceReference`. This method can be overridden in a subclass to customize the service object to be tracked for the service being added. In that case, take care not to rely on the default implementation of `removedService` to unget the service. Parameters reference:ServiceReference<S> The reference to the service being added to this `ServiceTracker`. Returns:T The service object to be tracked for the service added to this `ServiceTracker`. See Also `ServiceTrackerCustomizer#addingService(ServiceReference)`

public T addingService(ServiceReference<S> reference)

Implements org.osgi.util.tracker.ServiceTrackerCustomizer.addingService.

Default implementation of the ServiceTrackerCustomizer.addingService method.

This method is only called when this ServiceTracker has been constructed with a null ServiceTrackerCustomizer argument.

This implementation returns the result of calling getService on the BundleContext with which this ServiceTracker was created passing the specified ServiceReference.

This method can be overridden in a subclass to customize the service object to be tracked for the service being added. In that case, take care not to rely on the default implementation of removedService to unget the service.

Parameters

reference:ServiceReference<S>: The reference to the service being added to this ServiceTracker.

Returns:T

The service object to be tracked for the service added to this ServiceTracker.

close back to summary

close	back to summary
public void close() Close this `ServiceTracker`. This method should be called when this `ServiceTracker` should end the tracking of services. This implementation calls `getServiceReferences()` to get the list of tracked services to remove.

public void close()

Close this ServiceTracker.

This method should be called when this ServiceTracker should end the tracking of services.

This implementation calls getServiceReferences() to get the list of tracked services to remove.

getInitialReferences back to summary

getInitialReferences	back to summary
private ServiceReference<S>[] getInitialReferences(boolean trackAllServices, String className, String filterString) throws InvalidSyntaxException Returns the list of initial `ServiceReference`s that will be tracked by this `ServiceTracker`. Parameters trackAllServices:boolean If `true`, use `getAllServiceReferences`. className:String The class name with which the service was registered, or `null` for all services. filterString:String The filter criteria or `null` for all services. Returns:ServiceReference<S>[] The list of initial `ServiceReference`s. Exceptions InvalidSyntaxException: If the specified filterString has an invalid syntax.

private ServiceReference<S>[] getInitialReferences(boolean trackAllServices, String className, String filterString) throws InvalidSyntaxException

Returns the list of initial ServiceReferences that will be tracked by this ServiceTracker.

Parameters

trackAllServices:boolean: If true, use getAllServiceReferences.
className:String: The class name with which the service was registered, or null for all services.
filterString:String: The filter criteria or null for all services.

Returns:ServiceReference<S>[]

The list of initial ServiceReferences.

Exceptions

InvalidSyntaxException:: If the specified filterString has an invalid syntax.

getService back to summary

getService	back to summary
public T getService(ServiceReference<S> reference) Returns the service object for the specified `ServiceReference` if the specified referenced service is being tracked by this `ServiceTracker`. Parameters reference:ServiceReference<S> The reference to the desired service. Returns:T A service object or `null` if the service referenced by the specified `ServiceReference` is not being tracked.

public T getService(ServiceReference<S> reference)

Returns the service object for the specified ServiceReference if the specified referenced service is being tracked by this ServiceTracker.

Parameters

reference:ServiceReference<S>: The reference to the desired service.

Returns:T

A service object or null if the service referenced by the specified ServiceReference is not being tracked.

getService back to summary

getService	back to summary
public T getService() Returns a service object for one of the services being tracked by this `ServiceTracker`. If any services are being tracked, this implementation returns the result of calling `getService(getServiceReference())`. Returns:T A service object or `null` if no services are being tracked.

public T getService()

Returns a service object for one of the services being tracked by this ServiceTracker.

If any services are being tracked, this implementation returns the result of calling getService(getServiceReference()).

Returns:T: A service object or null if no services are being tracked.

getServiceReference back to summary

getServiceReference	back to summary
public ServiceReference<S> getServiceReference() Returns a `ServiceReference` for one of the services being tracked by this `ServiceTracker`. If multiple services are being tracked, the service with the highest ranking (as specified in its `service.ranking` property) is returned. If there is a tie in ranking, the service with the lowest service id (as specified in its `service.id` property); that is, the service that was registered first is returned. This is the same algorithm used by `BundleContext.getServiceReference`. This implementation calls `getServiceReferences()` to get the list of references for the tracked services. Returns:ServiceReference<S> A `ServiceReference` or `null` if no services are being tracked. Since 1.1

public ServiceReference<S> getServiceReference()

Returns a ServiceReference for one of the services being tracked by this ServiceTracker.

If multiple services are being tracked, the service with the highest ranking (as specified in its service.ranking property) is returned. If there is a tie in ranking, the service with the lowest service id (as specified in its service.id property); that is, the service that was registered first is returned. This is the same algorithm used by BundleContext.getServiceReference.

This implementation calls getServiceReferences() to get the list of references for the tracked services.

Returns:ServiceReference<S>: A ServiceReference or null if no services are being tracked.
Since: 1.1

getServiceReferences back to summary

getServiceReferences	back to summary
public ServiceReference<S>[] getServiceReferences() Return an array of `ServiceReference`s for all services being tracked by this `ServiceTracker`. Returns:ServiceReference<S>[] Array of `ServiceReference`s or `null` if no services are being tracked.

public ServiceReference<S>[] getServiceReferences()

Return an array of ServiceReferences for all services being tracked by this ServiceTracker.

Returns:ServiceReference<S>[]: Array of ServiceReferences or null if no services are being tracked.

getServices back to summary

getServices	back to summary
public Object[] getServices() Return an array of service objects for all services being tracked by this `ServiceTracker`. This implementation calls `getServiceReferences()` to get the list of references for the tracked services and then calls `getService(ServiceReference)` for each reference to get the tracked service object. Returns:Object[] An array of service objects or `null` if no services are being tracked.

public Object[] getServices()

Return an array of service objects for all services being tracked by this ServiceTracker.

This implementation calls getServiceReferences() to get the list of references for the tracked services and then calls getService(ServiceReference) for each reference to get the tracked service object.

Returns:Object[]: An array of service objects or null if no services are being tracked.

getServices back to summary

getServices	back to summary
public T[] getServices(T[] array) Return an array of service objects for all services being tracked by this `ServiceTracker`. The runtime type of the returned array is that of the specified array. This implementation calls `getServiceReferences()` to get the list of references for the tracked services and then calls `getService(ServiceReference)` for each reference to get the tracked service object. Parameters array:T[] An array into which the tracked service objects will be stored, if the array is large enough. Returns:T[] An array of service objects being tracked. If the specified array is large enough to hold the result, then the specified array is returned. If the specified array is longer then necessary to hold the result, the array element after the last service object is set to `null`. If the specified array is not large enough to hold the result, a new array is created and returned. Since 1.5

public T[] getServices(T[] array)

Return an array of service objects for all services being tracked by this ServiceTracker. The runtime type of the returned array is that of the specified array.

Parameters

array:T[]: An array into which the tracked service objects will be stored, if the array is large enough.

Returns:T[]

An array of service objects being tracked. If the specified array is large enough to hold the result, then the specified array is returned. If the specified array is longer then necessary to hold the result, the array element after the last service object is set to null. If the specified array is not large enough to hold the result, a new array is created and returned.

Since

1.5

getTracked back to summary

getTracked	back to summary
public SortedMap<ServiceReference<S>, T> getTracked() Return a `SortedMap` of the `ServiceReference`s and service objects for all services being tracked by this `ServiceTracker`. The map is sorted in reverse natural order of `ServiceReference`. That is, the first entry is the service with the highest ranking and the lowest service id. Returns:SortedMap<ServiceReference<S>, T> A `SortedMap` with the `ServiceReference`s and service objects for all services being tracked by this `ServiceTracker`. If no services are being tracked, then the returned map is empty. Since 1.5

public SortedMap<ServiceReference<S>, T> getTracked()

Return a SortedMap of the ServiceReferences and service objects for all services being tracked by this ServiceTracker. The map is sorted in reverse natural order of ServiceReference. That is, the first entry is the service with the highest ranking and the lowest service id.

Returns:SortedMap<ServiceReference<S>, T>: A SortedMap with the ServiceReferences and service objects for all services being tracked by this ServiceTracker. If no services are being tracked, then the returned map is empty.
Since: 1.5

getTrackingCount back to summary

getTrackingCount	back to summary
public int getTrackingCount() Returns the tracking count for this `ServiceTracker`. The tracking count is initialized to 0 when this `ServiceTracker` is opened. Every time a service is added, modified or removed from this `ServiceTracker`, the tracking count is incremented. The tracking count can be used to determine if this `ServiceTracker` has added, modified or removed a service by comparing a tracking count value previously collected with the current tracking count value. If the value has not changed, then no service has been added, modified or removed from this `ServiceTracker` since the previous tracking count was collected. Returns:int The tracking count for this `ServiceTracker` or -1 if this `ServiceTracker` is not open. Since 1.2

public int getTrackingCount()

Returns the tracking count for this ServiceTracker. The tracking count is initialized to 0 when this ServiceTracker is opened. Every time a service is added, modified or removed from this ServiceTracker, the tracking count is incremented.

The tracking count can be used to determine if this ServiceTracker has added, modified or removed a service by comparing a tracking count value previously collected with the current tracking count value. If the value has not changed, then no service has been added, modified or removed from this ServiceTracker since the previous tracking count was collected.

Returns:int: The tracking count for this ServiceTracker or -1 if this ServiceTracker is not open.
Since: 1.2

isEmpty back to summary

isEmpty	back to summary
public boolean isEmpty() Return if this `ServiceTracker` is empty. Returns:boolean `true` if this `ServiceTracker` is not tracking any services. Since 1.5

public boolean isEmpty()

Return if this ServiceTracker is empty.

Returns:boolean: true if this ServiceTracker is not tracking any services.
Since: 1.5

modified	back to summary
pack-priv void modified() Called by the Tracked object whenever the set of tracked services is modified. Clears the cache.

modifiedService back to summary

modifiedService	back to summary
public void modifiedService(ServiceReference<S> reference, T service) Implements org.osgi.util.tracker.ServiceTrackerCustomizer.modifiedService. Default implementation of the `ServiceTrackerCustomizer.modifiedService` method. This method is only called when this `ServiceTracker` has been constructed with a `null ServiceTrackerCustomizer` argument. This implementation does nothing. Parameters reference:ServiceReference<S> The reference to modified service. service:T The service object for the modified service. See Also `ServiceTrackerCustomizer#modifiedService(ServiceReference, Object)`

public void modifiedService(ServiceReference<S> reference, T service)

Implements org.osgi.util.tracker.ServiceTrackerCustomizer.modifiedService.

Default implementation of the ServiceTrackerCustomizer.modifiedService method.

This method is only called when this ServiceTracker has been constructed with a null ServiceTrackerCustomizer argument.

This implementation does nothing.

Parameters

reference:ServiceReference<S>: The reference to modified service.
service:T: The service object for the modified service.

open back to summary

open	back to summary
public void open() Open this `ServiceTracker` and begin tracking services. This implementation calls `open(false)`. Exceptions IllegalStateException: If the `BundleContext` with which this `ServiceTracker` was created is no longer valid. See Also `open(boolean)`

public void open()

Open this ServiceTracker and begin tracking services.

This implementation calls open(false).

Exceptions

IllegalStateException:: If the BundleContext with which this ServiceTracker was created is no longer valid.

See Also

open(boolean)

open back to summary

open	back to summary
public void open(boolean trackAllServices) Open this `ServiceTracker` and begin tracking services. Services which match the search criteria specified when this `ServiceTracker` was created are now tracked by this `ServiceTracker`. Parameters trackAllServices:boolean If `true`, then this `ServiceTracker` will track all matching services regardless of class loader accessibility. If `false`, then this `ServiceTracker` will only track matching services which are class loader accessible to the bundle whose `BundleContext` is used by this `ServiceTracker`. Exceptions IllegalStateException: If the `BundleContext` with which this `ServiceTracker` was created is no longer valid. Since 1.3

public void open(boolean trackAllServices)

Open this ServiceTracker and begin tracking services.

Services which match the search criteria specified when this ServiceTracker was created are now tracked by this ServiceTracker.

Parameters

trackAllServices:boolean: If true, then this ServiceTracker will track all matching services regardless of class loader accessibility. If false, then this ServiceTracker will only track matching services which are class loader accessible to the bundle whose BundleContext is used by this ServiceTracker.

Exceptions

IllegalStateException:: If the BundleContext with which this ServiceTracker was created is no longer valid.

Since

1.3

remove back to summary

remove	back to summary
public void remove(ServiceReference<S> reference) Remove a service from this `ServiceTracker`. The specified service will be removed from this `ServiceTracker`. If the specified service was being tracked then the `ServiceTrackerCustomizer.removedService` method will be called for that service. Parameters reference:ServiceReference<S> The reference to the service to be removed.

public void remove(ServiceReference<S> reference)

Remove a service from this ServiceTracker. The specified service will be removed from this ServiceTracker. If the specified service was being tracked then the ServiceTrackerCustomizer.removedService method will be called for that service.

Parameters

reference:ServiceReference<S>: The reference to the service to be removed.

removedService back to summary

removedService	back to summary
public void removedService(ServiceReference<S> reference, T service) Implements org.osgi.util.tracker.ServiceTrackerCustomizer.removedService. Default implementation of the `ServiceTrackerCustomizer.removedService` method. This method is only called when this `ServiceTracker` has been constructed with a `null ServiceTrackerCustomizer` argument. This implementation calls `ungetService`, on the `BundleContext` with which this `ServiceTracker` was created, passing the specified `ServiceReference`. This method can be overridden in a subclass. If the default implementation of `addingService` method was used, this method must unget the service. Parameters reference:ServiceReference<S> The reference to removed service. service:T The service object for the removed service. See Also `ServiceTrackerCustomizer#removedService(ServiceReference, Object)`

public void removedService(ServiceReference<S> reference, T service)

Implements org.osgi.util.tracker.ServiceTrackerCustomizer.removedService.

Default implementation of the ServiceTrackerCustomizer.removedService method.

This method is only called when this ServiceTracker has been constructed with a null ServiceTrackerCustomizer argument.

This implementation calls ungetService, on the BundleContext with which this ServiceTracker was created, passing the specified ServiceReference.

This method can be overridden in a subclass. If the default implementation of addingService method was used, this method must unget the service.

Parameters

reference:ServiceReference<S>: The reference to removed service.
service:T: The service object for the removed service.

size back to summary

size	back to summary
public int size() Return the number of services being tracked by this `ServiceTracker`. Returns:int The number of services being tracked.

public int size()

Return the number of services being tracked by this ServiceTracker.

Returns:int: The number of services being tracked.

tracked	back to summary
private ServiceTracker<S, T>.Tracked tracked() Accessor method for the current Tracked object. This method is only intended to be used by the unsynchronized methods which do not modify the tracked field. Returns:ServiceTracker<S, T>.Tracked The current Tracked object.

tracked

back to summary

private ServiceTracker<S, T>.Tracked tracked()

Accessor method for the current Tracked object. This method is only intended to be used by the unsynchronized methods which do not modify the tracked field.

Returns:ServiceTracker<S, T>.Tracked: The current Tracked object.

waitForService back to summary

waitForService	back to summary
public T waitForService(long timeout) throws InterruptedException Wait for at least one service to be tracked by this `ServiceTracker`. This method will also return when this `ServiceTracker` is closed. It is strongly recommended that `waitForService` is not used during the calling of the `BundleActivator` methods. `BundleActivator` methods are expected to complete in a short period of time. This implementation calls `getService()` to determine if a service is being tracked. Parameters timeout:long The time interval in milliseconds to wait. If zero, the method will wait indefinitely. Returns:T Returns the result of `getService()`. Exceptions InterruptedException: If another thread has interrupted the current thread. IllegalArgumentException: If the value of timeout is negative.

public T waitForService(long timeout) throws InterruptedException

Wait for at least one service to be tracked by this ServiceTracker. This method will also return when this ServiceTracker is closed.

It is strongly recommended that waitForService is not used during the calling of the BundleActivator methods. BundleActivator methods are expected to complete in a short period of time.

This implementation calls getService() to determine if a service is being tracked.

Parameters

timeout:long: The time interval in milliseconds to wait. If zero, the method will wait indefinitely.

Returns:T

Returns the result of getService().

Exceptions

InterruptedException:: If another thread has interrupted the current thread.
IllegalArgumentException:: If the value of timeout is negative.

org.osgi.util.tracker back to summary

private Class ServiceTracker.AllTracked

Class Inheritance

extends ServiceTracker<S, T>.Tracked
implements AllServiceListener

java.lang.Object
org.osgi.util.tracker.AbstractTracked
org.osgi.util.tracker.ServiceTracker.Tracked
org.osgi.util.tracker.ServiceTracker.AllTracked

All Implemented Interfaces

org.osgi.framework.AllServiceListener, org.osgi.framework.ServiceListener, java.util.EventListener

Subclass of Tracked which implements the AllServiceListener interface. This class is used by the ServiceTracker if open is called with true.

Since: 1.3

Constructor Summary

Access	Constructor and Description
pack-priv	AllTracked() AllTracked constructor.

Method Summary

Inherited from org.osgi.util.tracker.ServiceTracker.Tracked:: customizerAdding customizerModified customizerRemoved modified serviceChanged

Constructor Detail

AllTracked	back to summary
pack-priv AllTracked() AllTracked constructor.

org.osgi.util.tracker back to summary

private Class ServiceTracker.Tracked

Class Inheritance

extends AbstractTracked<ServiceReference<S>, T, ServiceEvent>
implements ServiceListener

java.lang.Object
org.osgi.util.tracker.AbstractTracked
org.osgi.util.tracker.ServiceTracker.Tracked

All Implemented Interfaces

org.osgi.framework.ServiceListener, java.util.EventListener

Known Direct Subclasses

org.osgi.util.tracker.ServiceTracker.AllTracked

Inner class which subclasses AbstractTracked. This class is the ServiceListener object for the tracker.

Field Summary

Inherited from org.osgi.util.tracker.AbstractTracked:: closed DEBUG

Constructor Summary

Access	Constructor and Description
pack-priv	Tracked() Tracked constructor.

Method Summary

Modifier and Type	Method and Description
pack-priv final T	Returns: Customized object for the tracked item or `null` if the item is not to be tracked. customizerAdding(final ServiceReference<S> Item to be tracked. item, final ServiceEvent Action related object. related) Implements abstract org.osgi.util.tracker.AbstractTracked.customizerAdding. Call the specific customizer adding method.
pack-priv final void	customizerModified(final ServiceReference<S> Tracked item. item, final ServiceEvent Action related object. related, final T Customized object for the tracked item. object) Implements abstract org.osgi.util.tracker.AbstractTracked.customizerModified. Call the specific customizer modified method.
pack-priv final void	customizerRemoved(final ServiceReference<S> Tracked item. item, final ServiceEvent Action related object. related, final T Customized object for the tracked item. object) Implements abstract org.osgi.util.tracker.AbstractTracked.customizerRemoved. Call the specific customizer removed method.
pack-priv final void	modified() Overrides org.osgi.util.tracker.AbstractTracked.modified. Increment the tracking count and tell the tracker there was a modification.
public final void	serviceChanged(final ServiceEvent `ServiceEvent` object from the framework. event) Implements org.osgi.framework.ServiceListener.serviceChanged. `ServiceListener` method for the `ServiceTracker` class.

Inherited from org.osgi.util.tracker.AbstractTracked:: close copyEntries copyKeys getCustomizedObject getTrackingCount isEmpty setInitial size track trackInitial untrack

Constructor Detail

Tracked	back to summary
pack-priv Tracked() Tracked constructor.

Method Detail

customizerAdding back to summary

customizerAdding	back to summary
pack-priv final T customizerAdding(final ServiceReference<S> item, final ServiceEvent related) Implements abstract org.osgi.util.tracker.AbstractTracked.customizerAdding. Call the specific customizer adding method. This method must not be called while synchronized on this object. Parameters item:ServiceReference<S> Item to be tracked. related:ServiceEvent Action related object. Returns:T Customized object for the tracked item or `null` if the item is not to be tracked. Annotations @Override

pack-priv final T customizerAdding(final ServiceReference<S> item, final ServiceEvent related)

Implements abstract org.osgi.util.tracker.AbstractTracked.customizerAdding.

Call the specific customizer adding method. This method must not be called while synchronized on this object.

Parameters

item:ServiceReference<S>: Item to be tracked.
related:ServiceEvent: Action related object.

Returns:T

Customized object for the tracked item or null if the item is not to be tracked.

Annotations

@Override

customizerModified	back to summary
pack-priv final void customizerModified(final ServiceReference<S> item, final ServiceEvent related, final T object) Implements abstract org.osgi.util.tracker.AbstractTracked.customizerModified. Call the specific customizer modified method. This method must not be called while synchronized on this object. Parameters item:ServiceReference<S> Tracked item. related:ServiceEvent Action related object. object:T Customized object for the tracked item. Annotations @Override

customizerModified

back to summary

pack-priv final void customizerModified(final ServiceReference<S> item, final ServiceEvent related, final T object)

Implements abstract org.osgi.util.tracker.AbstractTracked.customizerModified.

Call the specific customizer modified method. This method must not be called while synchronized on this object.

Parameters

item:ServiceReference<S>: Tracked item.
related:ServiceEvent: Action related object.
object:T: Customized object for the tracked item.

Annotations

@Override

customizerRemoved	back to summary
pack-priv final void customizerRemoved(final ServiceReference<S> item, final ServiceEvent related, final T object) Implements abstract org.osgi.util.tracker.AbstractTracked.customizerRemoved. Call the specific customizer removed method. This method must not be called while synchronized on this object. Parameters item:ServiceReference<S> Tracked item. related:ServiceEvent Action related object. object:T Customized object for the tracked item. Annotations @Override

customizerRemoved

back to summary

pack-priv final void customizerRemoved(final ServiceReference<S> item, final ServiceEvent related, final T object)

Implements abstract org.osgi.util.tracker.AbstractTracked.customizerRemoved.

Call the specific customizer removed method. This method must not be called while synchronized on this object.

Parameters

item:ServiceReference<S>: Tracked item.
related:ServiceEvent: Action related object.
object:T: Customized object for the tracked item.

Annotations

@Override

modified	back to summary
pack-priv final void modified() Overrides org.osgi.util.tracker.AbstractTracked.modified. Increment the tracking count and tell the tracker there was a modification. Annotations @Override

modified

back to summary

pack-priv final void modified()

Overrides org.osgi.util.tracker.AbstractTracked.modified.

Increment the tracking count and tell the tracker there was a modification.

Annotations

@Override

serviceChanged back to summary

serviceChanged	back to summary
public final void serviceChanged(final ServiceEvent event) Implements org.osgi.framework.ServiceListener.serviceChanged. `ServiceListener` method for the `ServiceTracker` class. This method must NOT be synchronized to avoid deadlock potential. Parameters event:ServiceEvent `ServiceEvent` object from the framework.

public final void serviceChanged(final ServiceEvent event)

Implements org.osgi.framework.ServiceListener.serviceChanged.

ServiceListener method for the ServiceTracker class. This method must NOT be synchronized to avoid deadlock potential.

Parameters

event:ServiceEvent: ServiceEvent object from the framework.

public Class ServiceTracker<S, T>

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail

private Class ServiceTracker.AllTracked

Constructor Summary

Method Summary

Constructor Detail

private Class ServiceTracker.Tracked

Field Summary

Constructor Summary

Method Summary

Constructor Detail

Method Detail