org.eclipse.jetty.util
Class BlockingArrayQueue<E>

java.lang.Object
  java.util.AbstractCollection<E>
      java.util.AbstractList<E>
          org.eclipse.jetty.util.BlockingArrayQueue<E>

Type Parameters:

E - The element type

All Implemented Interfaces:

Iterable<E>, Collection<E>, BlockingQueue<E>, List<E>, Queue<E>

public class BlockingArrayQueue<E>
extends AbstractList<E>
implements BlockingQueue<E>

Queue backed by a circular array. This queue is uses a variant of the two lock queue algorithm to provide an efficient queue or list backed by a growable circular array. This queue also has a partial implementation of BlockingQueue, specifically the take() and poll(long, TimeUnit) methods. Unlike ArrayBlockingQueue, this class is able to grow and provides a blocking put call.

The queue has both a capacity (the size of the array currently allocated) and a limit (the maximum size that may be allocated), which defaults to Integer.MAX_VALUE.

Field Summary

int	DEFAULT_CAPACITY
int	DEFAULT_GROWTH

Fields inherited from class java.util.AbstractList

modCount

Constructor Summary

BlockingArrayQueue()
Create a growing partially blocking Queue

BlockingArrayQueue(int limit)
Create a fixed size partially blocking Queue

BlockingArrayQueue(int capacity, int growBy)
Create a growing partially blocking Queue.

BlockingArrayQueue(int capacity, int growBy, int limit)
Create a growing limited partially blocking Queue.

Method Summary

boolean	add(E e)
void	add(int index, E e)
void	clear()
int	drainTo(Collection<? super E> c)
int	drainTo(Collection<? super E> c, int maxElements)
E	element()
E	get(int index)
int	getCapacity()
int	getLimit()
boolean	isEmpty()
boolean	offer(E e)
boolean	offer(E o, long timeout, TimeUnit unit)
E	peek()
E	poll()
E	poll(long time, TimeUnit unit) Retrieves and removes the head of this queue, waiting if necessary up to the specified wait time if no elements are present on this queue.
void	put(E o)
int	remainingCapacity()
E	remove()
E	remove(int index)
E	set(int index, E e)
int	size()
E	take() Retrieves and removes the head of this queue, waiting if no elements are present on this queue.

Methods inherited from class java.util.AbstractList

addAll, equals, hashCode, indexOf, iterator, lastIndexOf, listIterator, listIterator, removeRange, subList

Methods inherited from class java.util.AbstractCollection

addAll, contains, containsAll, remove, removeAll, retainAll, toArray, toArray, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.concurrent.BlockingQueue

contains, remove

Methods inherited from interface java.util.Collection

addAll, containsAll, equals, hashCode, iterator, removeAll, retainAll, toArray, toArray

Methods inherited from interface java.util.List

addAll, contains, containsAll, remove, removeAll, retainAll, toArray, toArray

Field Detail

DEFAULT_CAPACITY

public final int DEFAULT_CAPACITY

See Also:

Constant Field Values

DEFAULT_GROWTH

public final int DEFAULT_GROWTH

See Also:

Constant Field Values

Constructor Detail

BlockingArrayQueue

public BlockingArrayQueue()

Create a growing partially blocking Queue

BlockingArrayQueue

public BlockingArrayQueue(int limit)

Create a fixed size partially blocking Queue

Parameters:

limit - The initial capacity and the limit.

BlockingArrayQueue

public BlockingArrayQueue(int capacity,
                          int growBy)

Create a growing partially blocking Queue.

Parameters:

capacity - Initial capacity

growBy - Incremental capacity.

BlockingArrayQueue

public BlockingArrayQueue(int capacity,
                          int growBy,
                          int limit)

Create a growing limited partially blocking Queue.

Parameters:

capacity - Initial capacity

growBy - Incremental capacity.

limit - maximum capacity.

Method Detail

getCapacity

public int getCapacity()

getLimit

public int getLimit()

add

public boolean add(E e)

Specified by:

add in interface Collection<E>

Specified by:

add in interface BlockingQueue<E>

Specified by:

add in interface List<E>

Specified by:

add in interface Queue<E>

Overrides:

add in class AbstractList<E>

element

public E element()

Specified by:

element in interface Queue<E>

peek

public E peek()

Specified by:

peek in interface Queue<E>

offer

public boolean offer(E e)

Specified by:

offer in interface BlockingQueue<E>

Specified by:

offer in interface Queue<E>

poll

public E poll()

Specified by:

poll in interface Queue<E>

take

public E take()
       throws InterruptedException

Retrieves and removes the head of this queue, waiting if no elements are present on this queue.

Specified by:

take in interface BlockingQueue<E>

Returns:

the head of this queue

Throws:

InterruptedException - if interrupted while waiting.

poll

public E poll(long time,
              TimeUnit unit)
       throws InterruptedException

Retrieves and removes the head of this queue, waiting if necessary up to the specified wait time if no elements are present on this queue.

Specified by:

poll in interface BlockingQueue<E>

Parameters:

time - how long to wait before giving up, in units of unit

unit - a TimeUnit determining how to interpret the timeout parameter

Returns:

the head of this queue, or null if the specified waiting time elapses before an element is present.

Throws:

InterruptedException - if interrupted while waiting.

remove

public E remove()

Specified by:

remove in interface Queue<E>

clear

public void clear()

Specified by:

clear in interface Collection<E>

Specified by:

clear in interface List<E>

Overrides:

clear in class AbstractList<E>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Collection<E>

Specified by:

isEmpty in interface List<E>

Overrides:

isEmpty in class AbstractCollection<E>

size

public int size()

Specified by:

size in interface Collection<E>

Specified by:

size in interface List<E>

Specified by:

size in class AbstractCollection<E>

get

public E get(int index)

Specified by:

get in interface List<E>

Specified by:

get in class AbstractList<E>

remove

public E remove(int index)

Specified by:

remove in interface List<E>

Overrides:

remove in class AbstractList<E>

set

public E set(int index,
             E e)

Specified by:

set in interface List<E>

Overrides:

set in class AbstractList<E>

add

public void add(int index,
                E e)

Specified by:

add in interface List<E>

Overrides:

add in class AbstractList<E>

drainTo

public int drainTo(Collection<? super E> c)

Specified by:

drainTo in interface BlockingQueue<E>

drainTo

public int drainTo(Collection<? super E> c,
                   int maxElements)

Specified by:

drainTo in interface BlockingQueue<E>

offer

public boolean offer(E o,
                     long timeout,
                     TimeUnit unit)
              throws InterruptedException

Specified by:

offer in interface BlockingQueue<E>

Throws:

InterruptedException

put

public void put(E o)
         throws InterruptedException

Specified by:

put in interface BlockingQueue<E>

Throws:

InterruptedException

remainingCapacity

public int remainingCapacity()

Specified by:

remainingCapacity in interface BlockingQueue<E>