net.rim.pushsdk.commons
Class LinkedBlockingQueue<E>

java.lang.Object
  java.util.AbstractCollection<E>
      java.util.AbstractQueue<E>
          net.rim.pushsdk.commons.LinkedBlockingQueue<E>

All Implemented Interfaces:

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

public class LinkedBlockingQueue<E>
extends AbstractQueue<E>
implements BlockingQueue<E>, Serializable

Custom code copied from JDK 1.6.0 source that applies the fix suggested in this bug report: http://bugs.sun.com/view_bug.do;jsessionid=262f6941e032aaffffffffe6162904a49811d?bug_id=6805775

Author:

mdicesare

See Also:

Serialized Form

Constructor Summary

LinkedBlockingQueue()
Creates a LinkedBlockingQueue with a capacity of Integer.MAX_VALUE.

LinkedBlockingQueue(Collection<? extends E> c)
Creates a LinkedBlockingQueue with a capacity of Integer.MAX_VALUE, initially containing the elements of the given collection, added in traversal order of the collection's iterator.

LinkedBlockingQueue(int capacity)
Creates a LinkedBlockingQueue with the given (fixed) capacity.

Method Summary
void	clear() Atomically removes all of the elements from this queue.
int	drainTo(Collection<? super E> c)
int	drainTo(Collection<? super E> c, int maxElements)
Iterator<E>	iterator() Returns an iterator over the elements in this queue in proper sequence.
boolean	offer(E e) Inserts the specified element at the tail of this queue if it is possible to do so immediately without exceeding the queue's capacity, returning true upon success and false if this queue is full.
boolean	offer(E e, long timeout, TimeUnit unit) Inserts the specified element at the tail of this queue, waiting if necessary up to the specified wait time for space to become available.
E	peek()
E	poll()
E	poll(long timeout, TimeUnit unit)
void	put(E e) Inserts the specified element at the tail of this queue, waiting if necessary for space to become available.
int	remainingCapacity() Returns the number of additional elements that this queue can ideally (in the absence of memory or resource constraints) accept without blocking.
boolean	remove(Object o) Removes a single instance of the specified element from this queue, if it is present.
int	size() Returns the number of elements in this queue.
E	take()
Object[]	toArray() Returns an array containing all of the elements in this queue, in proper sequence.
<T> T[]	toArray(T[] a) Returns an array containing all of the elements in this queue, in proper sequence; the runtime type of the returned array is that of the specified array.
String	toString()

Methods inherited from class java.util.AbstractQueue

add, addAll, element, remove

Methods inherited from class java.util.AbstractCollection

contains, containsAll, isEmpty, removeAll, retainAll

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.concurrent.BlockingQueue

add, contains

Methods inherited from interface java.util.Queue

element, remove

Methods inherited from interface java.util.Collection

addAll, containsAll, equals, hashCode, isEmpty, removeAll, retainAll

Constructor Detail

LinkedBlockingQueue

public LinkedBlockingQueue()

Creates a LinkedBlockingQueue with a capacity of Integer.MAX_VALUE.

LinkedBlockingQueue

public LinkedBlockingQueue(int capacity)

Creates a LinkedBlockingQueue with the given (fixed) capacity.

Parameters:

capacity - the capacity of this queue

Throws:

IllegalArgumentException - if capacity is not greater than zero

LinkedBlockingQueue

public LinkedBlockingQueue(Collection<? extends E> c)

Creates a LinkedBlockingQueue with a capacity of Integer.MAX_VALUE, initially containing the elements of the given collection, added in traversal order of the collection's iterator.

Parameters:

c - the collection of elements to initially contain

Throws:

NullPointerException - if the specified collection or any of its elements are null

Method Detail

size

public int size()

Returns the number of elements in this queue.

Specified by:

size in interface Collection<E>

Specified by:

size in class AbstractCollection<E>

Returns:

the number of elements in this queue

remainingCapacity

public int remainingCapacity()

Returns the number of additional elements that this queue can ideally (in the absence of memory or resource constraints) accept without blocking. This is always equal to the initial capacity of this queue less the current size of this queue.

Note that you cannot always tell if an attempt to insert an element will succeed by inspecting remainingCapacity because it may be the case that another thread is about to insert or remove an element.

Specified by:

remainingCapacity in interface BlockingQueue<E>

put

public void put(E e)
         throws InterruptedException

Inserts the specified element at the tail of this queue, waiting if necessary for space to become available.

Specified by:

put in interface BlockingQueue<E>

Throws:

InterruptedException

NullPointerException

offer

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

Inserts the specified element at the tail of this queue, waiting if necessary up to the specified wait time for space to become available.

Specified by:

offer in interface BlockingQueue<E>

Returns:

true if successful, or false if the specified waiting time elapses before space is available.

Throws:

InterruptedException

NullPointerException

offer

public boolean offer(E e)

Inserts the specified element at the tail of this queue if it is possible to do so immediately without exceeding the queue's capacity, returning true upon success and false if this queue is full. When using a capacity-restricted queue, this method is generally preferable to method add, which can fail to insert an element only by throwing an exception.

Specified by:

offer in interface BlockingQueue<E>

Specified by:

offer in interface Queue<E>

Throws:

NullPointerException - if the specified element is null

take

public E take()
       throws InterruptedException

Specified by:

take in interface BlockingQueue<E>

Throws:

InterruptedException

poll

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

Specified by:

poll in interface BlockingQueue<E>

Throws:

InterruptedException

poll

public E poll()

Specified by:

poll in interface Queue<E>

peek

public E peek()

Specified by:

peek in interface Queue<E>

remove

public boolean remove(Object o)

Removes a single instance of the specified element from this queue, if it is present. More formally, removes an element e such that o.equals(e), if this queue contains one or more such elements. Returns true if this queue contained the specified element (or equivalently, if this queue changed as a result of the call).

Specified by:

remove in interface Collection<E>

Specified by:

remove in interface BlockingQueue<E>

Overrides:

remove in class AbstractCollection<E>

Parameters:

o - element to be removed from this queue, if present

Returns:

true if this queue changed as a result of the call

toArray

public Object[] toArray()

Returns an array containing all of the elements in this queue, in proper sequence.

The returned array will be "safe" in that no references to it are maintained by this queue. (In other words, this method must allocate a new array). The caller is thus free to modify the returned array.

This method acts as bridge between array-based and collection-based APIs.

Specified by:

toArray in interface Collection<E>

Overrides:

toArray in class AbstractCollection<E>

Returns:

an array containing all of the elements in this queue

toArray

public <T> T[] toArray(T[] a)

Returns an array containing all of the elements in this queue, in proper sequence; the runtime type of the returned array is that of the specified array. If the queue fits in the specified array, it is returned therein. Otherwise, a new array is allocated with the runtime type of the specified array and the size of this queue.

If this queue fits in the specified array with room to spare (i.e., the array has more elements than this queue), the element in the array immediately following the end of the queue is set to null.

Like the toArray() method, this method acts as bridge between array-based and collection-based APIs. Further, this method allows precise control over the runtime type of the output array, and may, under certain circumstances, be used to save allocation costs.

Suppose x is a queue known to contain only strings. The following code can be used to dump the queue into a newly allocated array of String:

 String[] y = x.toArray(new String[0]);
 

Note that toArray(new Object[0]) is identical in function to toArray().

Specified by:

toArray in interface Collection<E>

Overrides:

toArray in class AbstractCollection<E>

Parameters:

a - the array into which the elements of the queue are to be stored, if it is big enough; otherwise, a new array of the same runtime type is allocated for this purpose

Returns:

an array containing all of the elements in this queue

Throws:

ArrayStoreException - if the runtime type of the specified array is not a supertype of the runtime type of every element in this queue

NullPointerException - if the specified array is null

toString

public String toString()

Overrides:

toString in class AbstractCollection<E>

clear

public void clear()

Atomically removes all of the elements from this queue. The queue will be empty after this call returns.

Specified by:

clear in interface Collection<E>

Overrides:

clear in class AbstractQueue<E>

drainTo

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

Specified by:

drainTo in interface BlockingQueue<E>

Throws:

UnsupportedOperationException

ClassCastException

NullPointerException

IllegalArgumentException

drainTo

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

Specified by:

drainTo in interface BlockingQueue<E>

Throws:

UnsupportedOperationException

ClassCastException

NullPointerException

IllegalArgumentException

iterator

public Iterator<E> iterator()

Returns an iterator over the elements in this queue in proper sequence. The returned Iterator is a "weakly consistent" iterator that will never throw ConcurrentModificationException, and guarantees to traverse elements as they existed upon construction of the iterator, and may (but is not guaranteed to) reflect any modifications subsequent to construction.

Specified by:

iterator in interface Iterable<E>

Specified by:

iterator in interface Collection<E>

Specified by:

iterator in class AbstractCollection<E>

Returns:

an iterator over the elements in this queue in proper sequence