Package rx.internal.operators

Class OperatorReplay.InnerProducer<T>

  • Type Parameters:
    T - the value type
    All Implemented Interfaces:
    java.io.Serializable, Producer, Subscription
    Enclosing class:
    OperatorReplay<T>
    static final class OperatorReplay.InnerProducer<T>
extends java.util.concurrent.atomic.AtomicLong
implements Producer, Subscription
    A Producer and Subscription that manages the request and unsubscription state of a child subscriber in thread-safe manner. We use AtomicLong as a base class to save on extra allocation of an AtomicLong and also save the overhead of the AtomicIntegerFieldUpdater.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      (package private) Subscriber<? super T> child
      The actual child subscriber.
      (package private) boolean emitting
      Indicates an emission state.
      (package private) java.lang.Object index
      Holds an object that represents the current location in the buffer.
      (package private) boolean missed
      Indicates a missed update.
      (package private) OperatorReplay.ReplaySubscriber<T> parent
      The parent subscriber-to-source used to allow removing the child in case of child unsubscription.
      private static long serialVersionUID  
      (package private) java.util.concurrent.atomic.AtomicLong totalRequested
      Keeps the sum of all requested amounts.
      (package private) static long UNSUBSCRIBED
      Indicates this child has been unsubscribed: the state is swapped in atomically and will prevent the dispatch() to emit (too many) values to a terminated child subscriber.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      (package private) void addTotalRequested​(long n)
      Increments the total requested amount.
      (package private) <U> U index()
      Convenience method to auto-cast the index object.
      boolean isUnsubscribed()
      Indicates whether this Subscription is currently unsubscribed.
      long produced​(long n)
      Indicate that values have been emitted to this child subscriber by the dispatch() method.
      void request​(long n)
      Request a certain maximum number of items from this Producer.
      void unsubscribe()
      Stops the receipt of notifications on the Subscriber that was registered when this Subscription was received.

      • Methods inherited from class java.util.concurrent.atomic.AtomicLong

        accumulateAndGet, addAndGet, compareAndExchange, compareAndExchangeAcquire, compareAndExchangeRelease, compareAndSet, decrementAndGet, doubleValue, floatValue, get, getAcquire, getAndAccumulate, getAndAdd, getAndDecrement, getAndIncrement, getAndSet, getAndUpdate, getOpaque, getPlain, incrementAndGet, intValue, lazySet, longValue, set, setOpaque, setPlain, setRelease, toString, updateAndGet, weakCompareAndSet, weakCompareAndSetAcquire, weakCompareAndSetPlain, weakCompareAndSetRelease, weakCompareAndSetVolatile

      • Methods inherited from class java.lang.Number

        byteValue, shortValue

      • Methods inherited from class java.lang.Object

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

    • Field Detail

      • child

        Subscriber<? super T> child
        The actual child subscriber.

      • index

        java.lang.Object index
        Holds an object that represents the current location in the buffer. Guarded by the emitter loop.

      • totalRequested

        final java.util.concurrent.atomic.AtomicLong totalRequested
        Keeps the sum of all requested amounts.

      • emitting

        boolean emitting
        Indicates an emission state. Guarded by this.

      • missed

        boolean missed
        Indicates a missed update. Guarded by this.

      • UNSUBSCRIBED

        static final long UNSUBSCRIBED
        Indicates this child has been unsubscribed: the state is swapped in atomically and will prevent the dispatch() to emit (too many) values to a terminated child subscriber.
        See Also:
        Constant Field Values

    • Method Detail

      • request

        public void request​(long n)
        Description copied from interface: Producer
        Request a certain maximum number of items from this Producer. This is a way of requesting backpressure. To disable backpressure, pass Long.MAX_VALUE to this method.

        Requests are additive but if a sequence of requests totals more than Long.MAX_VALUE then Long.MAX_VALUE requests will be actioned and the extras may be ignored. Arriving at Long.MAX_VALUE by addition of requests cannot be assumed to disable backpressure. For example, the code below may result in Long.MAX_VALUE requests being actioned only. 

         request(100);
 request(Long.MAX_VALUE-1);
        Specified by:
        request in interface Producer
        Parameters:
        n - the maximum number of items you want this Producer to produce, or Long.MAX_VALUE if you want the Producer to produce items at its own pace

      • addTotalRequested

        void addTotalRequested​(long n)
        Increments the total requested amount.
        Parameters:
        n - the additional request amount

      • produced

        public long produced​(long n)
        Indicate that values have been emitted to this child subscriber by the dispatch() method.
        Parameters:
        n - the number of items emitted
        Returns:
        the updated request value (may indicate how much can be produced or a terminal state)

      • isUnsubscribed

        public boolean isUnsubscribed()
        Description copied from interface: Subscription
        Indicates whether this Subscription is currently unsubscribed.
        Specified by:
        isUnsubscribed in interface Subscription
        Returns:
        true if this Subscription is currently unsubscribed, false otherwise

      • unsubscribe

        public void unsubscribe()
        Description copied from interface: Subscription
        Stops the receipt of notifications on the Subscriber that was registered when this Subscription was received.

        This allows unregistering an Subscriber before it has finished receiving all events (i.e. before onCompleted is called).

        Specified by:
        unsubscribe in interface Subscription

      • index

        <U> U index()
        Convenience method to auto-cast the index object.
        Returns: