LinkedBlockingDeque

public class LinkedBlockingDeque extends AbstractQueue<E>
implements BlockingDeque<E> Serializable

An optionally-bounded {@linkplain BlockingDeque blocking deque} based on linked nodes.

The optional capacity bound constructor argument serves as a way to prevent excessive expansion. The capacity, if unspecified, is equal to MAX_VALUE. Linked nodes are dynamically created upon each insertion unless this would bring the deque above capacity.

Most operations run in constant time (ignoring time spent blocking). Exceptions include remove, removeFirstOccurrence, removeLastOccurrence, contains, iterator.remove(), and the bulk operations, all of which run in linear time.

This class and its iterator implement all of the optional methods of the Collection and Iterator interfaces.

Public Constructor Summary

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

Public Method Summary

boolean
add(E e)
Inserts the specified element at the end of this deque unless it would violate capacity restrictions.
void
addFirst(E e)
Inserts the specified element at the front of this deque if it is possible to do so immediately without violating capacity restrictions, throwing an IllegalStateException if no space is currently available.
void
addLast(E e)
Inserts the specified element at the end of this deque if it is possible to do so immediately without violating capacity restrictions, throwing an IllegalStateException if no space is currently available.
void
clear()
Atomically removes all of the elements from this deque.
boolean
contains(Object o)
Returns true if this deque contains the specified element.
Iterator<E>
descendingIterator()
Returns an iterator over the elements in this deque in reverse sequential order.
int
drainTo(Collection<? super E> c, int maxElements)
Removes at most the given number of available elements from this queue and adds them to the given collection.
int
drainTo(Collection<? super E> c)
Removes all available elements from this queue and adds them to the given collection.
E
element()
Retrieves, but does not remove, the head of the queue represented by this deque.
E
getFirst()
Retrieves, but does not remove, the first element of this deque.
E
getLast()
Retrieves, but does not remove, the last element of this deque.
Iterator<E>
iterator()
Returns an iterator over the elements in this deque in proper sequence.
boolean
offer(E e, long timeout, TimeUnit unit)
Inserts the specified element into the queue represented by this deque (in other words, at the tail of this deque), waiting up to the specified wait time if necessary for space to become available.
boolean
offer(E e)
Inserts the specified element into the queue represented by this deque (in other words, at the tail of this deque) if it is possible to do so immediately without violating capacity restrictions, returning true upon success and false if no space is currently available.
boolean
offerFirst(E e)
Inserts the specified element at the front of this deque if it is possible to do so immediately without violating capacity restrictions, returning true upon success and false if no space is currently available.
boolean
offerFirst(E e, long timeout, TimeUnit unit)
Inserts the specified element at the front of this deque, waiting up to the specified wait time if necessary for space to become available.
boolean
offerLast(E e)
Inserts the specified element at the end of this deque if it is possible to do so immediately without violating capacity restrictions, returning true upon success and false if no space is currently available.
boolean
offerLast(E e, long timeout, TimeUnit unit)
Inserts the specified element at the end of this deque, waiting up to the specified wait time if necessary for space to become available.
E
peek()
Retrieves, but does not remove, the head of the queue represented by this deque (in other words, the first element of this deque), or returns null if this deque is empty.
E
peekFirst()
Retrieves, but does not remove, the first element of this deque, or returns null if this deque is empty.
E
peekLast()
Retrieves, but does not remove, the last element of this deque, or returns null if this deque is empty.
E
poll(long timeout, TimeUnit unit)
Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque), waiting up to the specified wait time if necessary for an element to become available.
E
poll()
Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque), or returns null if this deque is empty.
E
pollFirst()
Retrieves and removes the first element of this deque, or returns null if this deque is empty.
E
pollFirst(long timeout, TimeUnit unit)
Retrieves and removes the first element of this deque, waiting up to the specified wait time if necessary for an element to become available.
E
pollLast(long timeout, TimeUnit unit)
Retrieves and removes the last element of this deque, waiting up to the specified wait time if necessary for an element to become available.
E
pollLast()
Retrieves and removes the last element of this deque, or returns null if this deque is empty.
E
pop()
Pops an element from the stack represented by this deque.
void
push(E e)
Pushes an element onto the stack represented by this deque (in other words, at the head of this deque) if it is possible to do so immediately without violating capacity restrictions, throwing an IllegalStateException if no space is currently available.
void
put(E e)
Inserts the specified element into the queue represented by this deque (in other words, at the tail of this deque), waiting if necessary for space to become available.
void
putFirst(E e)
Inserts the specified element at the front of this deque, waiting if necessary for space to become available.
void
putLast(E e)
Inserts the specified element at the end of this deque, waiting if necessary for space to become available.
int