Class MultithreadConcurrentQueue<E>

java.lang.Object
com.conversantmedia.util.concurrent.MultithreadConcurrentQueue<E>
All Implemented Interfaces:
ConcurrentQueue<E>
Direct Known Subclasses:
DisruptorBlockingQueue
public class MultithreadConcurrentQueue<E> extends Object implements ConcurrentQueue<E>
This is the disruptor implemented for multiple simultaneous reader and writer threads. This data structure approaches 20-40ns for transfers on fast hardware. This code is optimized and tested using a 64bit HotSpot JVM on an Intel x86-64 environment. Other environments should be carefully tested before using in production. Created by jcairns on 5/29/14.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    protected final int
    size
     

  • Constructor Summary

    Constructors
    Constructor
    Description
    MultithreadConcurrentQueue(int capacity)
    Construct a blocking queue of the given fixed capacity.

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    capacity()
     
    void
    clear()
    clear the queue of all elements
    final boolean
    contains(Object o)
     
    final boolean
    isEmpty()
     
    boolean
    offer(E e)
    Add element t to the ring
    final E
    peek()
    return the first element in the queue
    E
    poll()
    remove the first element from the queue and return it
    int
    remove(E[] e)
    return all elements in the queue to the provided array, up to the size of the provided array.
    final int
    size()
    This implemention is known to be broken if preemption were to occur after reading the tail pointer.

    Methods inherited from class Object

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

  • Field Details

    • size

      protected final int size

  • Constructor Details

    • MultithreadConcurrentQueue

      public MultithreadConcurrentQueue(int capacity)
      Construct a blocking queue of the given fixed capacity. Note: actual capacity will be the next power of two larger than capacity.
      Parameters:
      capacity - maximum capacity of this queue

  • Method Details

    • offer

      public boolean offer(E e)
      Description copied from interface: ConcurrentQueue
      Add element t to the ring
      Specified by:
      offer in interface ConcurrentQueue<E>
      Parameters:
      e - - element to offer
      Returns:
      boolean - true if the operation succeeded

    • poll

      public E poll()
      Description copied from interface: ConcurrentQueue
      remove the first element from the queue and return it
      Specified by:
      poll in interface ConcurrentQueue<E>
      Returns:
      T

    • peek

      public final E peek()
      Description copied from interface: ConcurrentQueue
      return the first element in the queue
      Specified by:
      peek in interface ConcurrentQueue<E>
      Returns:
      E - The element

    • remove

      public int remove(E[] e)
      Description copied from interface: ConcurrentQueue
      return all elements in the queue to the provided array, up to the size of the provided array.
      Specified by:
      remove in interface ConcurrentQueue<E>
      Parameters:
      e - - The element array
      Returns:
      int - the number of elements added to t

    • size

      public final int size()
      This implemention is known to be broken if preemption were to occur after reading the tail pointer. Code should not depend on size for a correct result.
      Specified by:
      size in interface ConcurrentQueue<E>
      Returns:
      int - possibly the size, or possibly any value less than capacity()

    • capacity

      public int capacity()
      Specified by:
      capacity in interface ConcurrentQueue<E>
      Returns:
      int - the capacity of the queue

    • isEmpty

      public final boolean isEmpty()
      Specified by:
      isEmpty in interface ConcurrentQueue<E>
      Returns:
      boolean - true if the queue is currently empty

    • clear

      public void clear()
      Description copied from interface: ConcurrentQueue
      clear the queue of all elements
      Specified by:
      clear in interface ConcurrentQueue<E>

    • contains

      public final boolean contains(Object o)
      Specified by:
      contains in interface ConcurrentQueue<E>
      Parameters:
      o - - the object to test
      Returns:
      boolean - true if specified object is contained in the queue