LinkedBlockingDeque (Java Platform SE 6) (original) (raw)
java.util.concurrent
Class LinkedBlockingDeque
java.lang.Object
java.util.AbstractCollection
java.util.AbstractQueue
java.util.concurrent.LinkedBlockingDeque
Type Parameters:
E - the type of elements held in this collection
All Implemented Interfaces:
Serializable, Iterable, Collection, BlockingDeque, BlockingQueue, Deque, Queue
public class LinkedBlockingDeque
extends AbstractQueue
implements BlockingDeque, Serializable
An optionally-bounded 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 Integer.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.
This class is a member of the Java Collections Framework.
Since:
1.6
See Also:
| Constructor Summary |
|---|
| LinkedBlockingDeque() Creates a LinkedBlockingDeque with a capacity ofInteger.MAX_VALUE. |
| LinkedBlockingDeque(Collection<? extends E> c) Creates a LinkedBlockingDeque with a capacity ofInteger.MAX_VALUE, initially containing the elements of the given collection, added in traversal order of the collection's iterator. |
| LinkedBlockingDeque(int capacity) Creates a LinkedBlockingDeque with the given (fixed) capacity. |
| 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) Removes all available elements from this queue and adds them to the given collection. |
| int | [drainTo](../../../java/util/concurrent/LinkedBlockingDeque.html#drainTo%28java.util.Collection, int%29)(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. |
| 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) 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, returningtrue upon success and false if no space is currently available. |
| boolean | [offer](../../../java/util/concurrent/LinkedBlockingDeque.html#offer%28E, long, java.util.concurrent.TimeUnit%29)(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 | 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](../../../java/util/concurrent/LinkedBlockingDeque.html#offerFirst%28E, long, java.util.concurrent.TimeUnit%29)(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](../../../java/util/concurrent/LinkedBlockingDeque.html#offerLast%28E, long, java.util.concurrent.TimeUnit%29)(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() Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque), or returnsnull if this deque is empty. |
| E | [poll](../../../java/util/concurrent/LinkedBlockingDeque.html#poll%28long, java.util.concurrent.TimeUnit%29)(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 | pollFirst() Retrieves and removes the first element of this deque, or returns null if this deque is empty. |
| E | [pollFirst](../../../java/util/concurrent/LinkedBlockingDeque.html#pollFirst%28long, java.util.concurrent.TimeUnit%29)(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() Retrieves and removes the last element of this deque, or returns null if this deque is empty. |
| E | [pollLast](../../../java/util/concurrent/LinkedBlockingDeque.html#pollLast%28long, java.util.concurrent.TimeUnit%29)(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 | 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. |
| 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 | remainingCapacity() Returns the number of additional elements that this deque can ideally (in the absence of memory or resource constraints) accept without blocking. |
| E | remove() Retrieves and removes the head of the queue represented by this deque. |
| boolean | remove(Object o) Removes the first occurrence of the specified element from this deque. |
| E | removeFirst() Retrieves and removes the first element of this deque. |
| boolean | removeFirstOccurrence(Object o) Removes the first occurrence of the specified element from this deque. |
| E | removeLast() Retrieves and removes the last element of this deque. |
| boolean | removeLastOccurrence(Object o) Removes the last occurrence of the specified element from this deque. |
| int | size() Returns the number of elements in this deque. |
| E | take() Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque), waiting if necessary until an element becomes available. |
| E | takeFirst() Retrieves and removes the first element of this deque, waiting if necessary until an element becomes available. |
| E | takeLast() Retrieves and removes the last element of this deque, waiting if necessary until an element becomes available. |
| Object[] | toArray() Returns an array containing all of the elements in this deque, in proper sequence (from first to last element). |
| T[] | toArray(T[] a) Returns an array containing all of the elements in this deque, in proper sequence; the runtime type of the returned array is that of the specified array. |
| String | toString() Returns a string representation of this collection. |
| Methods inherited from class java.util.AbstractQueue |
|---|
| addAll |
| Methods inherited from class java.util.AbstractCollection |
|---|
| containsAll, isEmpty, removeAll, retainAll |
| Methods inherited from class java.lang.Object |
|---|
| clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, [wait](../../../java/lang/Object.html#wait%28long, int%29) |
| Methods inherited from interface java.util.Collection |
|---|
| addAll, containsAll, equals, hashCode, isEmpty, removeAll, retainAll |
| Constructor Detail |
|---|
LinkedBlockingDeque
public LinkedBlockingDeque()
Creates a LinkedBlockingDeque with a capacity ofInteger.MAX_VALUE.
LinkedBlockingDeque
public LinkedBlockingDeque(int capacity)
Creates a LinkedBlockingDeque with the given (fixed) capacity.
Parameters:
capacity - the capacity of this deque
Throws:
[IllegalArgumentException](../../../java/lang/IllegalArgumentException.html "class in java.lang") - if capacity is less than 1
LinkedBlockingDeque
public LinkedBlockingDeque(Collection<? extends E> c)
Creates a LinkedBlockingDeque with a capacity ofInteger.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](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified collection or any of its elements are null
| Method Detail |
|---|
addFirst
public void addFirst(E e)
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#addFirst%28E%29)
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. When using a capacity-restricted deque, it is generally preferable to use offerFirst.
Specified by:
[addFirst](../../../java/util/concurrent/BlockingDeque.html#addFirst%28E%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[addFirst](../../../java/util/Deque.html#addFirst%28E%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
e - the element to add
Throws:
[IllegalStateException](../../../java/lang/IllegalStateException.html "class in java.lang") - if the element cannot be added at this time due to capacity restrictions
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified element is null
addLast
public void addLast(E e)
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#addLast%28E%29)
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. When using a capacity-restricted deque, it is generally preferable to use offerLast.
Specified by:
[addLast](../../../java/util/concurrent/BlockingDeque.html#addLast%28E%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[addLast](../../../java/util/Deque.html#addLast%28E%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
e - the element to add
Throws:
[IllegalStateException](../../../java/lang/IllegalStateException.html "class in java.lang") - if the element cannot be added at this time due to capacity restrictions
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified element is null
offerFirst
public boolean offerFirst(E e)
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#offerFirst%28E%29)
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. When using a capacity-restricted deque, this method is generally preferable to the addFirst method, which can fail to insert an element only by throwing an exception.
Specified by:
[offerFirst](../../../java/util/concurrent/BlockingDeque.html#offerFirst%28E%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[offerFirst](../../../java/util/Deque.html#offerFirst%28E%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
e - the element to add
Returns:
true if the element was added to this deque, elsefalse
Throws:
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified element is null
offerLast
public boolean offerLast(E e)
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#offerLast%28E%29)
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. When using a capacity-restricted deque, this method is generally preferable to the addLast method, which can fail to insert an element only by throwing an exception.
Specified by:
[offerLast](../../../java/util/concurrent/BlockingDeque.html#offerLast%28E%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[offerLast](../../../java/util/Deque.html#offerLast%28E%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
e - the element to add
Returns:
true if the element was added to this deque, elsefalse
Throws:
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified element is null
putFirst
public void putFirst(E e) throws InterruptedException
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#putFirst%28E%29)
Inserts the specified element at the front of this deque, waiting if necessary for space to become available.
Specified by:
[putFirst](../../../java/util/concurrent/BlockingDeque.html#putFirst%28E%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
e - the element to add
Throws:
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified element is null
[InterruptedException](../../../java/lang/InterruptedException.html "class in java.lang") - if interrupted while waiting
putLast
public void putLast(E e) throws InterruptedException
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#putLast%28E%29)
Inserts the specified element at the end of this deque, waiting if necessary for space to become available.
Specified by:
[putLast](../../../java/util/concurrent/BlockingDeque.html#putLast%28E%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
e - the element to add
Throws:
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified element is null
[InterruptedException](../../../java/lang/InterruptedException.html "class in java.lang") - if interrupted while waiting
offerFirst
public boolean offerFirst(E e, long timeout, TimeUnit unit) throws InterruptedException
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#offerFirst%28E, long, java.util.concurrent.TimeUnit%29)
Inserts the specified element at the front of this deque, waiting up to the specified wait time if necessary for space to become available.
Specified by:
[offerFirst](../../../java/util/concurrent/BlockingDeque.html#offerFirst%28E, long, java.util.concurrent.TimeUnit%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
e - the element to add
timeout - how long to wait before giving up, in units ofunit
unit - a TimeUnit determining how to interpret thetimeout parameter
Returns:
true if successful, or false if the specified waiting time elapses before space is available
Throws:
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified element is null
[InterruptedException](../../../java/lang/InterruptedException.html "class in java.lang") - if interrupted while waiting
offerLast
public boolean offerLast(E e, long timeout, TimeUnit unit) throws InterruptedException
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#offerLast%28E, long, java.util.concurrent.TimeUnit%29)
Inserts the specified element at the end of this deque, waiting up to the specified wait time if necessary for space to become available.
Specified by:
[offerLast](../../../java/util/concurrent/BlockingDeque.html#offerLast%28E, long, java.util.concurrent.TimeUnit%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
e - the element to add
timeout - how long to wait before giving up, in units ofunit
unit - a TimeUnit determining how to interpret thetimeout parameter
Returns:
true if successful, or false if the specified waiting time elapses before space is available
Throws:
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified element is null
[InterruptedException](../../../java/lang/InterruptedException.html "class in java.lang") - if interrupted while waiting
removeFirst
public E removeFirst()
Description copied from interface: [Deque](../../../java/util/Deque.html#removeFirst%28%29)
Retrieves and removes the first element of this deque. This method differs from pollFirst only in that it throws an exception if this deque is empty.
Specified by:
[removeFirst](../../../java/util/Deque.html#removeFirst%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the head of this deque
Throws:
[NoSuchElementException](../../../java/util/NoSuchElementException.html "class in java.util") - if this deque is empty
removeLast
public E removeLast()
Description copied from interface: [Deque](../../../java/util/Deque.html#removeLast%28%29)
Retrieves and removes the last element of this deque. This method differs from pollLast only in that it throws an exception if this deque is empty.
Specified by:
[removeLast](../../../java/util/Deque.html#removeLast%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the tail of this deque
Throws:
[NoSuchElementException](../../../java/util/NoSuchElementException.html "class in java.util") - if this deque is empty
pollFirst
public E pollFirst()
Description copied from interface: [Deque](../../../java/util/Deque.html#pollFirst%28%29)
Retrieves and removes the first element of this deque, or returns null if this deque is empty.
Specified by:
[pollFirst](../../../java/util/Deque.html#pollFirst%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the head of this deque, or null if this deque is empty
pollLast
public E pollLast()
Description copied from interface: [Deque](../../../java/util/Deque.html#pollLast%28%29)
Retrieves and removes the last element of this deque, or returns null if this deque is empty.
Specified by:
[pollLast](../../../java/util/Deque.html#pollLast%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the tail of this deque, or null if this deque is empty
takeFirst
public E takeFirst() throws InterruptedException
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#takeFirst%28%29)
Retrieves and removes the first element of this deque, waiting if necessary until an element becomes available.
Specified by:
[takeFirst](../../../java/util/concurrent/BlockingDeque.html#takeFirst%28%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the head of this deque
Throws:
[InterruptedException](../../../java/lang/InterruptedException.html "class in java.lang") - if interrupted while waiting
takeLast
public E takeLast() throws InterruptedException
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#takeLast%28%29)
Retrieves and removes the last element of this deque, waiting if necessary until an element becomes available.
Specified by:
[takeLast](../../../java/util/concurrent/BlockingDeque.html#takeLast%28%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the tail of this deque
Throws:
[InterruptedException](../../../java/lang/InterruptedException.html "class in java.lang") - if interrupted while waiting
pollFirst
public E pollFirst(long timeout, TimeUnit unit) throws InterruptedException
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#pollFirst%28long, java.util.concurrent.TimeUnit%29)
Retrieves and removes the first element of this deque, waiting up to the specified wait time if necessary for an element to become available.
Specified by:
[pollFirst](../../../java/util/concurrent/BlockingDeque.html#pollFirst%28long, java.util.concurrent.TimeUnit%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
timeout - how long to wait before giving up, in units ofunit
unit - a TimeUnit determining how to interpret thetimeout parameter
Returns:
the head of this deque, or null if the specified waiting time elapses before an element is available
Throws:
[InterruptedException](../../../java/lang/InterruptedException.html "class in java.lang") - if interrupted while waiting
pollLast
public E pollLast(long timeout, TimeUnit unit) throws InterruptedException
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#pollLast%28long, java.util.concurrent.TimeUnit%29)
Retrieves and removes the last element of this deque, waiting up to the specified wait time if necessary for an element to become available.
Specified by:
[pollLast](../../../java/util/concurrent/BlockingDeque.html#pollLast%28long, java.util.concurrent.TimeUnit%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
timeout - how long to wait before giving up, in units ofunit
unit - a TimeUnit determining how to interpret thetimeout parameter
Returns:
the tail of this deque, or null if the specified waiting time elapses before an element is available
Throws:
[InterruptedException](../../../java/lang/InterruptedException.html "class in java.lang") - if interrupted while waiting
getFirst
public E getFirst()
Description copied from interface: [Deque](../../../java/util/Deque.html#getFirst%28%29)
Retrieves, but does not remove, the first element of this deque. This method differs from peekFirst only in that it throws an exception if this deque is empty.
Specified by:
[getFirst](../../../java/util/Deque.html#getFirst%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the head of this deque
Throws:
[NoSuchElementException](../../../java/util/NoSuchElementException.html "class in java.util") - if this deque is empty
getLast
public E getLast()
Description copied from interface: [Deque](../../../java/util/Deque.html#getLast%28%29)
Retrieves, but does not remove, the last element of this deque. This method differs from peekLast only in that it throws an exception if this deque is empty.
Specified by:
[getLast](../../../java/util/Deque.html#getLast%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the tail of this deque
Throws:
[NoSuchElementException](../../../java/util/NoSuchElementException.html "class in java.util") - if this deque is empty
peekFirst
public E peekFirst()
Description copied from interface: [Deque](../../../java/util/Deque.html#peekFirst%28%29)
Retrieves, but does not remove, the first element of this deque, or returns null if this deque is empty.
Specified by:
[peekFirst](../../../java/util/Deque.html#peekFirst%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the head of this deque, or null if this deque is empty
peekLast
public E peekLast()
Description copied from interface: [Deque](../../../java/util/Deque.html#peekLast%28%29)
Retrieves, but does not remove, the last element of this deque, or returns null if this deque is empty.
Specified by:
[peekLast](../../../java/util/Deque.html#peekLast%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the tail of this deque, or null if this deque is empty
removeFirstOccurrence
public boolean removeFirstOccurrence(Object o)
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#removeFirstOccurrence%28java.lang.Object%29)
Removes the first occurrence of the specified element from this deque. If the deque does not contain the element, it is unchanged. More formally, removes the first element e such thato.equals(e) (if such an element exists). Returns true if this deque contained the specified element (or equivalently, if this deque changed as a result of the call).
Specified by:
[removeFirstOccurrence](../../../java/util/concurrent/BlockingDeque.html#removeFirstOccurrence%28java.lang.Object%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[removeFirstOccurrence](../../../java/util/Deque.html#removeFirstOccurrence%28java.lang.Object%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
o - element to be removed from this deque, if present
Returns:
true if an element was removed as a result of this call
removeLastOccurrence
public boolean removeLastOccurrence(Object o)
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#removeLastOccurrence%28java.lang.Object%29)
Removes the last occurrence of the specified element from this deque. If the deque does not contain the element, it is unchanged. More formally, removes the last element e such thato.equals(e) (if such an element exists). Returns true if this deque contained the specified element (or equivalently, if this deque changed as a result of the call).
Specified by:
[removeLastOccurrence](../../../java/util/concurrent/BlockingDeque.html#removeLastOccurrence%28java.lang.Object%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[removeLastOccurrence](../../../java/util/Deque.html#removeLastOccurrence%28java.lang.Object%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
o - element to be removed from this deque, if present
Returns:
true if an element was removed as a result of this call
add
public boolean add(E e)
Inserts the specified element at the end of this deque unless it would violate capacity restrictions. When using a capacity-restricted deque, it is generally preferable to use method offer.
This method is equivalent to addLast(E).
Specified by:
[add](../../../java/util/Collection.html#add%28E%29) in interface [Collection](../../../java/util/Collection.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[add](../../../java/util/concurrent/BlockingDeque.html#add%28E%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[add](../../../java/util/concurrent/BlockingQueue.html#add%28E%29) in interface [BlockingQueue](../../../java/util/concurrent/BlockingQueue.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[add](../../../java/util/Deque.html#add%28E%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[add](../../../java/util/Queue.html#add%28E%29) in interface [Queue](../../../java/util/Queue.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Overrides:
[add](../../../java/util/AbstractQueue.html#add%28E%29) in class [AbstractQueue](../../../java/util/AbstractQueue.html "class in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
e - the element to add
Returns:
true (as specified by Collection.add(E))
Throws:
[IllegalStateException](../../../java/lang/IllegalStateException.html "class in java.lang") - if the element cannot be added at this time due to capacity restrictions
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified element is null
offer
public boolean offer(E e)
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#offer%28E%29)
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, returningtrue upon success and false if no space is currently available. When using a capacity-restricted deque, this method is generally preferable to the BlockingDeque.add(E) method, which can fail to insert an element only by throwing an exception.
This method is equivalent to offerLast.
Specified by:
[offer](../../../java/util/concurrent/BlockingDeque.html#offer%28E%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[offer](../../../java/util/concurrent/BlockingQueue.html#offer%28E%29) in interface [BlockingQueue](../../../java/util/concurrent/BlockingQueue.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[offer](../../../java/util/Deque.html#offer%28E%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[offer](../../../java/util/Queue.html#offer%28E%29) in interface [Queue](../../../java/util/Queue.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
e - the element to add
Returns:
true if the element was added to this queue, elsefalse
Throws:
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified element is null
put
public void put(E e) throws InterruptedException
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#put%28E%29)
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.
This method is equivalent to putLast.
Specified by:
[put](../../../java/util/concurrent/BlockingDeque.html#put%28E%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[put](../../../java/util/concurrent/BlockingQueue.html#put%28E%29) in interface [BlockingQueue](../../../java/util/concurrent/BlockingQueue.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
e - the element to add
Throws:
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified element is null
[InterruptedException](../../../java/lang/InterruptedException.html "class in java.lang") - if interrupted while waiting
offer
public boolean offer(E e, long timeout, TimeUnit unit) throws InterruptedException
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#offer%28E, long, java.util.concurrent.TimeUnit%29)
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.
This method is equivalent to[offerLast](../../../java/util/concurrent/BlockingDeque.html#offerLast%28E, long, java.util.concurrent.TimeUnit%29).
Specified by:
[offer](../../../java/util/concurrent/BlockingDeque.html#offer%28E, long, java.util.concurrent.TimeUnit%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[offer](../../../java/util/concurrent/BlockingQueue.html#offer%28E, long, java.util.concurrent.TimeUnit%29) in interface [BlockingQueue](../../../java/util/concurrent/BlockingQueue.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
e - the element to add
timeout - how long to wait before giving up, in units ofunit
unit - a TimeUnit determining how to interpret thetimeout parameter
Returns:
true if the element was added to this deque, elsefalse
Throws:
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified element is null
[InterruptedException](../../../java/lang/InterruptedException.html "class in java.lang") - if interrupted while waiting
remove
public E remove()
Retrieves and removes the head of the queue represented by this deque. This method differs from poll only in that it throws an exception if this deque is empty.
This method is equivalent to removeFirst.
Specified by:
[remove](../../../java/util/concurrent/BlockingDeque.html#remove%28%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[remove](../../../java/util/Deque.html#remove%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[remove](../../../java/util/Queue.html#remove%28%29) in interface [Queue](../../../java/util/Queue.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Overrides:
[remove](../../../java/util/AbstractQueue.html#remove%28%29) in class [AbstractQueue](../../../java/util/AbstractQueue.html "class in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the head of the queue represented by this deque
Throws:
[NoSuchElementException](../../../java/util/NoSuchElementException.html "class in java.util") - if this deque is empty
poll
public E poll()
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#poll%28%29)
Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque), or returnsnull if this deque is empty.
This method is equivalent to Deque.pollFirst().
Specified by:
[poll](../../../java/util/concurrent/BlockingDeque.html#poll%28%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[poll](../../../java/util/Deque.html#poll%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[poll](../../../java/util/Queue.html#poll%28%29) in interface [Queue](../../../java/util/Queue.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the head of this deque, or null if this deque is empty
take
public E take() throws InterruptedException
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#take%28%29)
Retrieves and removes the head of the queue represented by this deque (in other words, the first element of this deque), waiting if necessary until an element becomes available.
This method is equivalent to takeFirst.
Specified by:
[take](../../../java/util/concurrent/BlockingDeque.html#take%28%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[take](../../../java/util/concurrent/BlockingQueue.html#take%28%29) in interface [BlockingQueue](../../../java/util/concurrent/BlockingQueue.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the head of this deque
Throws:
[InterruptedException](../../../java/lang/InterruptedException.html "class in java.lang") - if interrupted while waiting
poll
public E poll(long timeout, TimeUnit unit) throws InterruptedException
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#poll%28long, java.util.concurrent.TimeUnit%29)
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.
This method is equivalent to[pollFirst](../../../java/util/concurrent/BlockingDeque.html#pollFirst%28long, java.util.concurrent.TimeUnit%29).
Specified by:
[poll](../../../java/util/concurrent/BlockingDeque.html#poll%28long, java.util.concurrent.TimeUnit%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[poll](../../../java/util/concurrent/BlockingQueue.html#poll%28long, java.util.concurrent.TimeUnit%29) in interface [BlockingQueue](../../../java/util/concurrent/BlockingQueue.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
timeout - how long to wait before giving up, in units ofunit
unit - a TimeUnit determining how to interpret thetimeout parameter
Returns:
the head of this deque, or null if the specified waiting time elapses before an element is available
Throws:
[InterruptedException](../../../java/lang/InterruptedException.html "class in java.lang") - if interrupted while waiting
element
public E element()
Retrieves, but does not remove, the head of the queue represented by this deque. This method differs from peek only in that it throws an exception if this deque is empty.
This method is equivalent to getFirst.
Specified by:
[element](../../../java/util/concurrent/BlockingDeque.html#element%28%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[element](../../../java/util/Deque.html#element%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[element](../../../java/util/Queue.html#element%28%29) in interface [Queue](../../../java/util/Queue.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Overrides:
[element](../../../java/util/AbstractQueue.html#element%28%29) in class [AbstractQueue](../../../java/util/AbstractQueue.html "class in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the head of the queue represented by this deque
Throws:
[NoSuchElementException](../../../java/util/NoSuchElementException.html "class in java.util") - if this deque is empty
peek
public E peek()
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#peek%28%29)
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.
This method is equivalent to peekFirst.
Specified by:
[peek](../../../java/util/concurrent/BlockingDeque.html#peek%28%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[peek](../../../java/util/Deque.html#peek%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[peek](../../../java/util/Queue.html#peek%28%29) in interface [Queue](../../../java/util/Queue.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the head of this deque, or null if this deque is empty
remainingCapacity
public int remainingCapacity()
Returns the number of additional elements that this deque can ideally (in the absence of memory or resource constraints) accept without blocking. This is always equal to the initial capacity of this deque less the current size of this deque.
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](../../../java/util/concurrent/BlockingQueue.html#remainingCapacity%28%29) in interface [BlockingQueue](../../../java/util/concurrent/BlockingQueue.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the remaining capacity
drainTo
public int drainTo(Collection<? super E> c)
Description copied from interface: [BlockingQueue](../../../java/util/concurrent/BlockingQueue.html#drainTo%28java.util.Collection%29)
Removes all available elements from this queue and adds them to the given collection. This operation may be more efficient than repeatedly polling this queue. A failure encountered while attempting to add elements to collection c may result in elements being in neither, either or both collections when the associated exception is thrown. Attempts to drain a queue to itself result inIllegalArgumentException. Further, the behavior of this operation is undefined if the specified collection is modified while the operation is in progress.
Specified by:
[drainTo](../../../java/util/concurrent/BlockingQueue.html#drainTo%28java.util.Collection%29) in interface [BlockingQueue](../../../java/util/concurrent/BlockingQueue.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
c - the collection to transfer elements into
Returns:
the number of elements transferred
Throws:
[UnsupportedOperationException](../../../java/lang/UnsupportedOperationException.html "class in java.lang") - if addition of elements is not supported by the specified collection
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the class of an element of this queue prevents it from being added to the specified collection
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified collection is null
[IllegalArgumentException](../../../java/lang/IllegalArgumentException.html "class in java.lang") - if the specified collection is this queue, or some property of an element of this queue prevents it from being added to the specified collection
drainTo
public int drainTo(Collection<? super E> c, int maxElements)
Description copied from interface: [BlockingQueue](../../../java/util/concurrent/BlockingQueue.html#drainTo%28java.util.Collection, int%29)
Removes at most the given number of available elements from this queue and adds them to the given collection. A failure encountered while attempting to add elements to collection c may result in elements being in neither, either or both collections when the associated exception is thrown. Attempts to drain a queue to itself result inIllegalArgumentException. Further, the behavior of this operation is undefined if the specified collection is modified while the operation is in progress.
Specified by:
[drainTo](../../../java/util/concurrent/BlockingQueue.html#drainTo%28java.util.Collection, int%29) in interface [BlockingQueue](../../../java/util/concurrent/BlockingQueue.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
c - the collection to transfer elements into
maxElements - the maximum number of elements to transfer
Returns:
the number of elements transferred
Throws:
[UnsupportedOperationException](../../../java/lang/UnsupportedOperationException.html "class in java.lang") - if addition of elements is not supported by the specified collection
[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang") - if the class of an element of this queue prevents it from being added to the specified collection
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified collection is null
[IllegalArgumentException](../../../java/lang/IllegalArgumentException.html "class in java.lang") - if the specified collection is this queue, or some property of an element of this queue prevents it from being added to the specified collection
push
public void push(E e)
Description copied from interface: [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html#push%28E%29)
Pushes an element onto the stack represented by this deque. In other words, inserts the element at the front of this deque unless it would violate capacity restrictions.
This method is equivalent to addFirst.
Specified by:
[push](../../../java/util/concurrent/BlockingDeque.html#push%28E%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[push](../../../java/util/Deque.html#push%28E%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
e - the element to push
Throws:
[IllegalStateException](../../../java/lang/IllegalStateException.html "class in java.lang") - if the element cannot be added at this time due to capacity restrictions
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified element is null
pop
public E pop()
Description copied from interface: [Deque](../../../java/util/Deque.html#pop%28%29)
Pops an element from the stack represented by this deque. In other words, removes and returns the first element of this deque.
This method is equivalent to Deque.removeFirst().
Specified by:
[pop](../../../java/util/Deque.html#pop%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the element at the front of this deque (which is the top of the stack represented by this deque)
Throws:
[NoSuchElementException](../../../java/util/NoSuchElementException.html "class in java.util") - if this deque is empty
remove
public boolean remove(Object o)
Removes the first occurrence of the specified element from this deque. If the deque does not contain the element, it is unchanged. More formally, removes the first element e such thato.equals(e) (if such an element exists). Returns true if this deque contained the specified element (or equivalently, if this deque changed as a result of the call).
This method is equivalent toremoveFirstOccurrence.
Specified by:
[remove](../../../java/util/Collection.html#remove%28java.lang.Object%29) in interface [Collection](../../../java/util/Collection.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[remove](../../../java/util/concurrent/BlockingDeque.html#remove%28java.lang.Object%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[remove](../../../java/util/concurrent/BlockingQueue.html#remove%28java.lang.Object%29) in interface [BlockingQueue](../../../java/util/concurrent/BlockingQueue.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[remove](../../../java/util/Deque.html#remove%28java.lang.Object%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Overrides:
[remove](../../../java/util/AbstractCollection.html#remove%28java.lang.Object%29) in class [AbstractCollection](../../../java/util/AbstractCollection.html "class in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
o - element to be removed from this deque, if present
Returns:
true if this deque changed as a result of the call
size
public int size()
Returns the number of elements in this deque.
Specified by:
[size](../../../java/util/Collection.html#size%28%29) in interface [Collection](../../../java/util/Collection.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[size](../../../java/util/concurrent/BlockingDeque.html#size%28%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[size](../../../java/util/Deque.html#size%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[size](../../../java/util/AbstractCollection.html#size%28%29) in class [AbstractCollection](../../../java/util/AbstractCollection.html "class in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
the number of elements in this deque
contains
public boolean contains(Object o)
Returns true if this deque contains the specified element. More formally, returns true if and only if this deque contains at least one element e such that o.equals(e).
Specified by:
[contains](../../../java/util/Collection.html#contains%28java.lang.Object%29) in interface [Collection](../../../java/util/Collection.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[contains](../../../java/util/concurrent/BlockingDeque.html#contains%28java.lang.Object%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[contains](../../../java/util/concurrent/BlockingQueue.html#contains%28java.lang.Object%29) in interface [BlockingQueue](../../../java/util/concurrent/BlockingQueue.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[contains](../../../java/util/Deque.html#contains%28java.lang.Object%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Overrides:
[contains](../../../java/util/AbstractCollection.html#contains%28java.lang.Object%29) in class [AbstractCollection](../../../java/util/AbstractCollection.html "class in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
o - object to be checked for containment in this deque
Returns:
true if this deque contains the specified element
toArray
public Object[] toArray()
Returns an array containing all of the elements in this deque, in proper sequence (from first to last element).
The returned array will be "safe" in that no references to it are maintained by this deque. (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](../../../java/util/Collection.html#toArray%28%29) in interface [Collection](../../../java/util/Collection.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Overrides:
[toArray](../../../java/util/AbstractCollection.html#toArray%28%29) in class [AbstractCollection](../../../java/util/AbstractCollection.html "class in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
an array containing all of the elements in this deque
toArray
public T[] toArray(T[] a)
Returns an array containing all of the elements in this deque, in proper sequence; the runtime type of the returned array is that of the specified array. If the deque 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 deque.
If this deque fits in the specified array with room to spare (i.e., the array has more elements than this deque), the element in the array immediately following the end of the deque is set tonull.
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 deque known to contain only strings. The following code can be used to dump the deque into a newly allocated array of String:
String[] y = x.toArray(new String[0]);Note that toArray(new Object[0]) is identical in function totoArray().
Specified by:
[toArray](../../../java/util/Collection.html#toArray%28T[]%29) in interface [Collection](../../../java/util/Collection.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Overrides:
[toArray](../../../java/util/AbstractCollection.html#toArray%28T[]%29) in class [AbstractCollection](../../../java/util/AbstractCollection.html "class in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Parameters:
a - the array into which the elements of the deque 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 deque
Throws:
[ArrayStoreException](../../../java/lang/ArrayStoreException.html "class in java.lang") - if the runtime type of the specified array is not a supertype of the runtime type of every element in this deque
[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang") - if the specified array is null
toString
public String toString()
Description copied from class: [AbstractCollection](../../../java/util/AbstractCollection.html#toString%28%29)
Returns a string representation of this collection. The string representation consists of a list of the collection's elements in the order they are returned by its iterator, enclosed in square brackets ("[]"). Adjacent elements are separated by the characters", " (comma and space). Elements are converted to strings as by String.valueOf(Object).
Overrides:
[toString](../../../java/util/AbstractCollection.html#toString%28%29) in class [AbstractCollection](../../../java/util/AbstractCollection.html "class in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
a string representation of this collection
clear
public void clear()
Atomically removes all of the elements from this deque. The deque will be empty after this call returns.
Specified by:
[clear](../../../java/util/Collection.html#clear%28%29) in interface [Collection](../../../java/util/Collection.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Overrides:
[clear](../../../java/util/AbstractQueue.html#clear%28%29) in class [AbstractQueue](../../../java/util/AbstractQueue.html "class in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
iterator
Returns an iterator over the elements in this deque in proper sequence. The elements will be returned in order from first (head) to last (tail). 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](../../../java/lang/Iterable.html#iterator%28%29) in interface [Iterable](../../../java/lang/Iterable.html "interface in java.lang")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[iterator](../../../java/util/Collection.html#iterator%28%29) in interface [Collection](../../../java/util/Collection.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[iterator](../../../java/util/concurrent/BlockingDeque.html#iterator%28%29) in interface [BlockingDeque](../../../java/util/concurrent/BlockingDeque.html "interface in java.util.concurrent")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[iterator](../../../java/util/Deque.html#iterator%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Specified by:
[iterator](../../../java/util/AbstractCollection.html#iterator%28%29) in class [AbstractCollection](../../../java/util/AbstractCollection.html "class in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
an iterator over the elements in this deque in proper sequence
descendingIterator
public Iterator<E> descendingIterator()
Returns an iterator over the elements in this deque in reverse sequential order. The elements will be returned in order from last (tail) to first (head). 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:
[descendingIterator](../../../java/util/Deque.html#descendingIterator%28%29) in interface [Deque](../../../java/util/Deque.html "interface in java.util")<[E](../../../java/util/concurrent/LinkedBlockingDeque.html "type parameter in LinkedBlockingDeque")>
Returns:
an iterator over the elements in this deque in reverse sequence
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