程序包 java.util.concurrent

类 LinkedBlockingDeque<E>

java.lang.Object

java.util.AbstractCollection<E>

java.util.AbstractQueue<E>

java.util.concurrent.LinkedBlockingDeque<E>

类型参数:

E - the type of elements held in this collection

所有已实现的接口:

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

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

An optionally-bounded BlockingDeque 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.

从以下版本开始:

1.6

另请参阅:

序列化表格

构造器概要

构造器

构造器	说明
LinkedBlockingDeque()	Creates a LinkedBlockingDeque with a capacity of Integer#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 Integer#MAX_VALUE, initially containing the elements of the given collection, added in traversal order of the collection's iterator.

方法概要

限定符和类型	方法	说明
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(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, returning true upon success and false if no space is currently available.
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	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()	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	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	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()	Retrieves and removes the last element of this deque, or returns null if this deque is empty.
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	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	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.
Spliterator<E>	spliterator()	Returns a Spliterator over the 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> 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.

从类继承的方法 java.util.AbstractCollection

containsAll, isEmpty, removeAll, retainAll

从类继承的方法 java.util.AbstractQueue

addAll

从接口继承的方法 java.util.Collection

addAll, containsAll, equals, hashCode, isEmpty, parallelStream, removeAll, removeIf, retainAll, stream

从接口继承的方法 java.lang.Iterable

forEach

从类继承的方法 java.lang.Object

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

构造器详细资料

LinkedBlockingDeque

public LinkedBlockingDeque()

Creates a LinkedBlockingDeque with a capacity of Integer#MAX_VALUE.

LinkedBlockingDeque

public LinkedBlockingDeque(int capacity)

Creates a LinkedBlockingDeque with the given (fixed) capacity.

参数:

capacity - the capacity of this deque

抛出:

IllegalArgumentException - if capacity is less than 1

LinkedBlockingDeque

public LinkedBlockingDeque(Collection<? extends E> c)

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

参数:

c - the collection of elements to initially contain

抛出:

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

方法详细资料

addFirst

public void addFirst(E e)

从接口复制的说明: BlockingDeque

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.

指定者:

addFirst 在接口中 BlockingDeque<E>

指定者:

addFirst 在接口中 Deque<E>

参数:

e - the element to add

抛出:

IllegalStateException - if this deque is full

NullPointerException - if the specified element is null

addLast

public void addLast(E e)

从接口复制的说明: BlockingDeque

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.

指定者:

addLast 在接口中 BlockingDeque<E>

指定者:

addLast 在接口中 Deque<E>

参数:

e - the element to add

抛出:

IllegalStateException - if this deque is full

NullPointerException - if the specified element is null

offerFirst

public boolean offerFirst(E e)

从接口复制的说明: BlockingDeque

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.

指定者:

offerFirst 在接口中 BlockingDeque<E>

指定者:

offerFirst 在接口中 Deque<E>

参数:

e - the element to add

返回:

true if the element was added to this deque, else false

抛出:

NullPointerException - if the specified element is null

offerLast

public boolean offerLast(E e)

从接口复制的说明: BlockingDeque

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.

指定者:

offerLast 在接口中 BlockingDeque<E>

指定者:

offerLast 在接口中 Deque<E>

参数:

e - the element to add

返回:

true if the element was added to this deque, else false

抛出:

NullPointerException - if the specified element is null

putFirst

public void putFirst(E e)
              throws InterruptedException

从接口复制的说明: BlockingDeque

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

指定者:

putFirst 在接口中 BlockingDeque<E>

参数:

e - the element to add

抛出:

NullPointerException - if the specified element is null

InterruptedException - if interrupted while waiting

putLast

public void putLast(E e)
             throws InterruptedException

从接口复制的说明: BlockingDeque

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

指定者:

putLast 在接口中 BlockingDeque<E>

参数:

e - the element to add

抛出:

NullPointerException - if the specified element is null

InterruptedException - if interrupted while waiting

offerFirst

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

从接口复制的说明: BlockingDeque

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

指定者:

offerFirst 在接口中 BlockingDeque<E>

参数:

e - the element to add

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

unit - a TimeUnit determining how to interpret the timeout parameter

返回:

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

抛出:

NullPointerException - if the specified element is null

InterruptedException - if interrupted while waiting

offerLast

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

从接口复制的说明: BlockingDeque

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

指定者:

offerLast 在接口中 BlockingDeque<E>

参数:

e - the element to add

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

unit - a TimeUnit determining how to interpret the timeout parameter

返回:

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

抛出:

NullPointerException - if the specified element is null

InterruptedException - if interrupted while waiting

removeFirst

public E removeFirst()

从接口复制的说明: Deque

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.

指定者:

removeFirst 在接口中 Deque<E>

返回:

the head of this deque

抛出:

NoSuchElementException - if this deque is empty

removeLast

public E removeLast()

从接口复制的说明: Deque

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.

指定者:

removeLast 在接口中 Deque<E>

返回:

the tail of this deque

抛出:

NoSuchElementException - if this deque is empty

pollFirst

public E pollFirst()

从接口复制的说明: Deque

Retrieves and removes the first element of this deque, or returns null if this deque is empty.

指定者:

pollFirst 在接口中 Deque<E>

返回:

the head of this deque, or null if this deque is empty

pollLast

public E pollLast()

从接口复制的说明: Deque

Retrieves and removes the last element of this deque, or returns null if this deque is empty.

指定者:

pollLast 在接口中 Deque<E>

返回:

the tail of this deque, or null if this deque is empty

takeFirst

public E takeFirst()
            throws InterruptedException

从接口复制的说明: BlockingDeque

Retrieves and removes the first element of this deque, waiting if necessary until an element becomes available.

指定者:

takeFirst 在接口中 BlockingDeque<E>

返回:

the head of this deque

抛出:

InterruptedException - if interrupted while waiting

takeLast

public E takeLast()
           throws InterruptedException

从接口复制的说明: BlockingDeque

Retrieves and removes the last element of this deque, waiting if necessary until an element becomes available.

指定者:

takeLast 在接口中 BlockingDeque<E>

返回:

the tail of this deque

抛出:

InterruptedException - if interrupted while waiting

pollFirst

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

从接口复制的说明: BlockingDeque

Retrieves and removes the first element of this deque, waiting up to the specified wait time if necessary for an element to become available.

指定者:

pollFirst 在接口中 BlockingDeque<E>

参数:

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

unit - a TimeUnit determining how to interpret the timeout parameter

返回:

the head of this deque, or null if the specified waiting time elapses before an element is available

抛出:

InterruptedException - if interrupted while waiting

pollLast

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

从接口复制的说明: BlockingDeque

Retrieves and removes the last element of this deque, waiting up to the specified wait time if necessary for an element to become available.

指定者:

pollLast 在接口中 BlockingDeque<E>

参数:

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

unit - a TimeUnit determining how to interpret the timeout parameter

返回:

the tail of this deque, or null if the specified waiting time elapses before an element is available

抛出:

InterruptedException - if interrupted while waiting

getFirst

public E getFirst()

从接口复制的说明: Deque

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.

指定者:

getFirst 在接口中 Deque<E>

返回:

the head of this deque

抛出:

NoSuchElementException - if this deque is empty

getLast

public E getLast()

从接口复制的说明: Deque

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.

指定者:

getLast 在接口中 Deque<E>

返回:

the tail of this deque

抛出:

NoSuchElementException - if this deque is empty

peekFirst

public E peekFirst()

从接口复制的说明: Deque

Retrieves, but does not remove, the first element of this deque, or returns null if this deque is empty.

指定者:

peekFirst 在接口中 Deque<E>

返回:

the head of this deque, or null if this deque is empty

peekLast

public E peekLast()

从接口复制的说明: Deque

Retrieves, but does not remove, the last element of this deque, or returns null if this deque is empty.

指定者:

peekLast 在接口中 Deque<E>

返回:

the tail of this deque, or null if this deque is empty

removeFirstOccurrence

public boolean removeFirstOccurrence(Object o)

从接口复制的说明: BlockingDeque

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 that o.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).

指定者:

removeFirstOccurrence 在接口中 BlockingDeque<E>

指定者:

removeFirstOccurrence 在接口中 Deque<E>

参数:

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

返回:

true if an element was removed as a result of this call

removeLastOccurrence

public boolean removeLastOccurrence(Object o)

从接口复制的说明: BlockingDeque

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 that o.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).

指定者:

removeLastOccurrence 在接口中 BlockingDeque<E>

指定者:

removeLastOccurrence 在接口中 Deque<E>

参数:

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

返回:

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).

指定者:

add 在接口中 BlockingDeque<E>

指定者:

add 在接口中 BlockingQueue<E>

指定者:

add 在接口中 Collection<E>

指定者:

add 在接口中 Deque<E>

指定者:

add 在接口中 Queue<E>

覆盖:

add 在类中 AbstractQueue<E>

参数:

e - the element to add

返回:

true (as specified by Collection#add)

抛出:

IllegalStateException - if this deque is full

NullPointerException - if the specified element is null

offer

public boolean offer(E e)

从接口复制的说明: BlockingDeque

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. 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.

指定者:

offer 在接口中 BlockingDeque<E>

指定者:

offer 在接口中 BlockingQueue<E>

指定者:

offer 在接口中 Deque<E>

指定者:

offer 在接口中 Queue<E>

参数:

e - the element to add

返回:

true if the element was added to this queue, else false

抛出:

NullPointerException - if the specified element is null

put

public void put(E e)
         throws InterruptedException

从接口复制的说明: BlockingDeque

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.

指定者:

put 在接口中 BlockingDeque<E>

指定者:

put 在接口中 BlockingQueue<E>

参数:

e - the element to add

抛出:

NullPointerException - if the specified element is null

InterruptedException - if interrupted while waiting

offer

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

从接口复制的说明: BlockingDeque

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.

指定者:

offer 在接口中 BlockingDeque<E>

指定者:

offer 在接口中 BlockingQueue<E>

参数:

e - the element to add

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

unit - a TimeUnit determining how to interpret the timeout parameter

返回:

true if the element was added to this deque, else false

抛出:

NullPointerException - if the specified element is null

InterruptedException - 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.

指定者:

remove 在接口中 BlockingDeque<E>

指定者:

remove 在接口中 Deque<E>

指定者:

remove 在接口中 Queue<E>

覆盖:

remove 在类中 AbstractQueue<E>

返回:

the head of the queue represented by this deque

抛出:

NoSuchElementException - if this deque is empty

poll

public E poll()

从接口复制的说明: BlockingDeque

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.

This method is equivalent to Deque.pollFirst().

指定者:

poll 在接口中 BlockingDeque<E>

指定者:

poll 在接口中 Deque<E>

指定者:

poll 在接口中 Queue<E>

返回:

the head of this deque, or null if this deque is empty

take

public E take()
       throws InterruptedException

从接口复制的说明: BlockingDeque

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.

指定者:

take 在接口中 BlockingDeque<E>

指定者:

take 在接口中 BlockingQueue<E>

返回:

the head of this deque

抛出:

InterruptedException - if interrupted while waiting

poll

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

从接口复制的说明: BlockingDeque

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.

指定者:

poll 在接口中 BlockingDeque<E>

指定者:

poll 在接口中 BlockingQueue<E>

参数:

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

unit - a TimeUnit determining how to interpret the timeout parameter

返回:

the head of this deque, or null if the specified waiting time elapses before an element is available

抛出:

InterruptedException - 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.

指定者:

element 在接口中 BlockingDeque<E>

指定者:

element 在接口中 Deque<E>

指定者:

element 在接口中 Queue<E>

覆盖:

element 在类中 AbstractQueue<E>

返回:

the head of the queue represented by this deque

抛出:

NoSuchElementException - if this deque is empty

peek

public E peek()

从接口复制的说明: BlockingDeque

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.

指定者:

peek 在接口中 BlockingDeque<E>

指定者:

peek 在接口中 Deque<E>

指定者:

peek 在接口中 Queue<E>

返回:

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.

指定者:

remainingCapacity 在接口中 BlockingQueue<E>

返回:

the remaining capacity

drainTo

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

从接口复制的说明: BlockingQueue

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 in IllegalArgumentException. Further, the behavior of this operation is undefined if the specified collection is modified while the operation is in progress.

指定者:

drainTo 在接口中 BlockingQueue<E>

参数:

c - the collection to transfer elements into

返回:

the number of elements transferred

抛出:

UnsupportedOperationException - if addition of elements is not supported by the specified collection

ClassCastException - if the class of an element of this queue prevents it from being added to the specified collection

NullPointerException - if the specified collection is null

IllegalArgumentException - 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)

从接口复制的说明: BlockingQueue

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 in IllegalArgumentException. Further, the behavior of this operation is undefined if the specified collection is modified while the operation is in progress.

指定者:

drainTo 在接口中 BlockingQueue<E>

参数:

c - the collection to transfer elements into

maxElements - the maximum number of elements to transfer

返回:

the number of elements transferred

抛出:

UnsupportedOperationException - if addition of elements is not supported by the specified collection

ClassCastException - if the class of an element of this queue prevents it from being added to the specified collection

NullPointerException - if the specified collection is null

IllegalArgumentException - 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)

从接口复制的说明: BlockingDeque

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.

This method is equivalent to addFirst.

指定者:

push 在接口中 BlockingDeque<E>

指定者:

push 在接口中 Deque<E>

参数:

e - the element to push

抛出:

IllegalStateException - if this deque is full

NullPointerException - if the specified element is null

pop

public E pop()

从接口复制的说明: Deque

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().

指定者:

pop 在接口中 Deque<E>

返回:

the element at the front of this deque (which is the top of the stack represented by this deque)

抛出:

NoSuchElementException - 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 that o.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 to removeFirstOccurrence.

指定者:

remove 在接口中 BlockingDeque<E>

指定者:

remove 在接口中 BlockingQueue<E>

指定者:

remove 在接口中 Collection<E>

指定者:

remove 在接口中 Deque<E>

覆盖:

remove 在类中 AbstractCollection<E>

参数:

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

返回:

true if this deque changed as a result of the call

size

public int size()

Returns the number of elements in this deque.

指定者:

size 在接口中 BlockingDeque<E>

指定者:

size 在接口中 Collection<E>

指定者:

size 在接口中 Deque<E>

指定者:

size 在类中 AbstractCollection<E>

返回:

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).

指定者:

contains 在接口中 BlockingDeque<E>

指定者:

contains 在接口中 BlockingQueue<E>

指定者:

contains 在接口中 Collection<E>

指定者:

contains 在接口中 Deque<E>

覆盖:

contains 在类中 AbstractCollection<E>

参数:

o - object to be checked for containment in this deque

返回:

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.

指定者:

toArray 在接口中 Collection<E>

覆盖:

toArray 在类中 AbstractCollection<E>

返回:

an array containing all of the elements in this deque

toArray

public <T> 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 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 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 to toArray().

指定者:

toArray 在接口中 Collection<E>

覆盖:

toArray 在类中 AbstractCollection<E>

类型参数:

T - the runtime type of the array to contain the collection

参数:

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

返回:

an array containing all of the elements in this deque

抛出:

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

NullPointerException - if the specified array is null

toString

public String toString()

从类复制的说明: AbstractCollection

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).

覆盖:

toString 在类中 AbstractCollection<E>

返回:

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.

指定者:

clear 在接口中 Collection<E>

覆盖:

clear 在类中 AbstractQueue<E>

iterator

public Iterator<E> 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 weakly consistent.

指定者:

iterator 在接口中 BlockingDeque<E>

指定者:

iterator 在接口中 Collection<E>

指定者:

iterator 在接口中 Deque<E>

指定者:

iterator 在接口中 Iterable<E>

指定者:

iterator 在类中 AbstractCollection<E>

返回:

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 weakly consistent.

指定者:

descendingIterator 在接口中 Deque<E>

返回:

an iterator over the elements in this deque in reverse order

spliterator

public Spliterator<E> spliterator()

Returns a Spliterator over the elements in this deque.

The returned spliterator is weakly consistent.

The Spliterator reports Spliterator#CONCURRENT, Spliterator#ORDERED, and Spliterator#NONNULL.

指定者:

spliterator 在接口中 Collection<E>

指定者:

spliterator 在接口中 Iterable<E>

返回:

a Spliterator over the elements in this deque

从以下版本开始:

1.8