Package io.objectbox

Class ObjectClassPublisher

java.lang.Object

io.objectbox.ObjectClassPublisher

All Implemented Interfaces:

DataPublisher<Class>, Runnable

@Internal
class ObjectClassPublisher
extends Object
implements DataPublisher<Class>, Runnable

A DataPublisher that notifies DataObservers about changes in an entity box. Publishing is requested when a subscription is observed and then by BoxStore for each txCommitted. Publish requests are processed on a single thread, one at a time, in the order publishing was requested.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	ObjectClassPublisher.PublishRequest

Field Summary

Fields

Modifier and Type	Field	Description
(package private) final BoxStore	boxStore
(package private) boolean	changePublisherRunning
private final Deque<ObjectClassPublisher.PublishRequest>	changesQueue
(package private) final org.greenrobot.essentials.collections.MultimapSet<Integer,DataObserver<Class>>	observersByEntityTypeId

Constructor Summary

Constructors

Constructor	Description
ObjectClassPublisher(BoxStore boxStore)

Method Summary

Modifier and Type	Method	Description
private void	handleObserverException(Class objectClass)
(package private) void	publish(int[] entityTypeIdsAffected)
void	publishSingle(DataObserver<Class> observer, Object forClass)
private void	queuePublishRequestAndScheduleRun(DataObserver<Class> observer, int[] entityTypeIds)	Non-blocking: will just enqueue the changes for a separate thread.
void	run()	Processes publish requests using a single thread to prevent any data generated by observers to get stale.
void	subscribe(DataObserver<Class> observer, Object forClass)
private void	unsubscribe(DataObserver<Class> observer, int entityTypeId)
void	unsubscribe(DataObserver<Class> observer, Object forClass)	Removes the given observer from all object classes it added itself to earlier (forClass == null).

Methods inherited from class java.lang.Object

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

Field Details

boxStore

final BoxStore boxStore

observersByEntityTypeId

final org.greenrobot.essentials.collections.MultimapSet<Integer,DataObserver<Class>> observersByEntityTypeId

changesQueue

private final Deque<ObjectClassPublisher.PublishRequest> changesQueue

changePublisherRunning

volatile boolean changePublisherRunning

Constructor Details

ObjectClassPublisher

ObjectClassPublisher(BoxStore boxStore)

Method Details

subscribe

public void subscribe(DataObserver<Class> observer,
 @Nullable
 Object forClass)

Specified by:

subscribe in interface DataPublisher<Class>

unsubscribe

public void unsubscribe(DataObserver<Class> observer,
 @Nullable
 Object forClass)

Removes the given observer from all object classes it added itself to earlier (forClass == null). This also considers weakly added observers.

Specified by:

unsubscribe in interface DataPublisher<Class>

unsubscribe

private void unsubscribe(DataObserver<Class> observer,
 int entityTypeId)

publishSingle

public void publishSingle(DataObserver<Class> observer,
 @Nullable
 Object forClass)

Specified by:

publishSingle in interface DataPublisher<Class>

publish

void publish(int[] entityTypeIdsAffected)

queuePublishRequestAndScheduleRun

private void queuePublishRequestAndScheduleRun(@Nullable
 DataObserver<Class> observer,
 int[] entityTypeIds)

Non-blocking: will just enqueue the changes for a separate thread.

run

public void run()

Processes publish requests using a single thread to prevent any data generated by observers to get stale. This publisher on its own can NOT deliver stale data (the entity class types do not change). However, a DataObserver of this publisher might apply a DataTransformer which queries for data which CAN get stale if delivered out of order.

Specified by:

run in interface Runnable

handleObserverException

private void handleObserverException(Class objectClass)