rx.internal.util

Class IndexedRingBuffer<E>

java.lang.Object

rx.internal.util.IndexedRingBuffer<E>

Type Parameters:

E -

All Implemented Interfaces:

Subscription

public final class IndexedRingBuffer<E>
extends java.lang.Object
implements Subscription

Add/Remove without object allocation (after initial construction).

This is meant for hundreds or single-digit thousands of elements that need to be rapidly added and randomly or sequentially removed while avoiding object allocation.

On Intel Core i7, 2.3Mhz, Mac Java 8:

- adds per second single-threaded => ~32,598,500 for 100 - adds per second single-threaded => ~23,200,000 for 10,000 - adds + removes per second single-threaded => 15,562,100 for 100 - adds + removes per second single-threaded => 8,760,000 for 10,000

 Benchmark                                              (size)   Mode   Samples        Score  Score error    Units
 r.i.IndexedRingBufferPerf.indexedRingBufferAdd            100  thrpt         5   263571.721     9856.994    ops/s
 r.i.IndexedRingBufferPerf.indexedRingBufferAdd          10000  thrpt         5     1763.417      211.998    ops/s
 r.i.IndexedRingBufferPerf.indexedRingBufferAddRemove      100  thrpt         5   139850.115    17143.705    ops/s
 r.i.IndexedRingBufferPerf.indexedRingBufferAddRemove    10000  thrpt         5      809.982       72.931    ops/s
  

Method Summary

Methods

Modifier and Type	Method and Description
int	add(E e) Add an element and return the index where it was added to allow removal.
int	forEach(Func1<? super E,java.lang.Boolean> action)
int	forEach(Func1<? super E,java.lang.Boolean> action, int startIndex)
static IndexedRingBuffer	getInstance()
boolean	isUnsubscribed() Indicates whether this Subscription is currently unsubscribed.
void	releaseToPool() This resets the arrays, nulls out references and returns it to the pool.
E	remove(int index)
void	unsubscribe() Stops the receipt of notifications on the Subscriber that was registered when this Subscription was received.

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static final IndexedRingBuffer getInstance()

releaseToPool

public void releaseToPool()

This resets the arrays, nulls out references and returns it to the pool. This extra CPU cost is far smaller than the object allocation cost of not pooling.

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

add

public int add(E e)

Add an element and return the index where it was added to allow removal.

Parameters:

e -

Returns:

remove

public E remove(int index)

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

forEach

public int forEach(Func1<? super E,java.lang.Boolean> action)

forEach

public int forEach(Func1<? super E,java.lang.Boolean> action,
          int startIndex)

Parameters:

action - that processes each item and returns true if it wants to continue to the next

Returns:

int of next index to process, or last index seen if it exited early