Package slash.navigation.converter.gui.helpers

Class ServiceRegistry

java.lang.Object

slash.navigation.converter.gui.helpers.ServiceRegistry

public class ServiceRegistry
extends Object

Owns the lazily-initialised, shared services that used to live directly on BaseRouteConverter: the map view, the audio player (TimeAlbum) and the position augmenter. Each accessor is guarded by a single private lock so a service is created at most once, even under concurrent first access (issue #214) -- the class does not change what is created or when, only where the field and its lock live.

positionAugmenter and audioPlayer follow the classic double-checked-locking-over-a-volatile-field pattern: created on first access. mapView is a holder instead -- it is not created on demand but explicitly replaced by setMapView(String, MapViewSwapped), whose callback runs while this class's lock is held, so the field swap and the caller's Swing wiring (adding the new view's component to a panel) are one atomic step from the outside; the lock itself is never handed out (a getLock() accessor trips SpotBugs' USO_UNSAFE_ACCESSIBLE_OBJECT_SYNCHRONIZATION).

Author:

Christian Pesch

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	ServiceRegistry.MapViewSwapped	Runs while setMapView(String, MapViewSwapped) holds this registry's lock, so the field swap and whatever Swing wiring the caller does for the new view are one atomic step to outside readers of getMapView() / isMapViewAvailable().

Constructor Summary

Constructors

Constructor	Description
ServiceRegistry(Supplier<JTable> positionsViewSupplier, Supplier<PositionsModel> positionsModelSupplier, Supplier<JFrame> frameSupplier, ElevationServiceFacade elevationServiceFacade, GeocodingServiceFacade geocodingServiceFacade)

Method Summary

Modifier and Type	Method	Description
void	dispose()	Disposes whichever services have been created so far.
AudioPlayer	getAudioPlayer()
MapView	getMapView()
PositionAugmenter	getPositionAugmenter()
boolean	isMapViewAvailable()
void	setMapView(String className, ServiceRegistry.MapViewSwapped callback)	Creates a new map view from className, disposes the previous one (if there was one) and installs the new one -- all while holding this registry's lock, with callback invoked in between so the caller can do its Swing wiring atomically with the field swap.

Methods inherited from class java.lang.Object

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

Constructor Details

ServiceRegistry

public ServiceRegistry(Supplier<JTable> positionsViewSupplier,
 Supplier<PositionsModel> positionsModelSupplier,
 Supplier<JFrame> frameSupplier,
 ElevationServiceFacade elevationServiceFacade,
 GeocodingServiceFacade geocodingServiceFacade)

Method Details

getMapView

public MapView getMapView()

setMapView

public void setMapView(String className,
 ServiceRegistry.MapViewSwapped callback)

Creates a new map view from className, disposes the previous one (if there was one) and installs the new one -- all while holding this registry's lock, with callback invoked in between so the caller can do its Swing wiring atomically with the field swap.

isMapViewAvailable

public boolean isMapViewAvailable()

getPositionAugmenter

public PositionAugmenter getPositionAugmenter()

getAudioPlayer

public AudioPlayer getAudioPlayer()

dispose

public void dispose()

Disposes whichever services have been created so far. Idempotent: a second call is a no-op. A service accessed again after dispose() is not recreated -- the accessor keeps returning the same, now disposed, instance, matching the behaviour before this extraction.