LinkedBlockingDeque
open class LinkedBlockingDeque<E : Any!> : AbstractQueue<E>, BlockingDeque<E>, 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(java.lang.Object), #removeFirstOccurrence, #removeLastOccurrence, #contains, #iterator, 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.
Summary
| Public constructors |
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Creates a LinkedBlockingDeque with a capacity of Integer.MAX_VALUE.
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Creates a LinkedBlockingDeque with the given (fixed) capacity.
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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.
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| Public methods |
| open Boolean |
Inserts the specified element at the end of this deque unless it would violate capacity restrictions.
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| open Boolean |
Appends all of the elements in the specified collection to the end of this deque, in the order that they are returned by the specified collection's iterator.
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| open Unit |
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| open Unit |
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| open Unit |
Atomically removes all of the elements from this deque.
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| open Boolean |
Returns true if this deque contains the specified element.
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| open MutableIterator<E> |
Returns an iterator over the elements in this deque in reverse sequential order.
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| open Int |
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| open Int |
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| open E |
Retrieves, but does not remove, the head of the queue represented by this deque.
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| open Unit |
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| open E |
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| open E |
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| open MutableIterator<E> |
Returns an iterator over the elements in this deque in proper sequence.
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| open Boolean |
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| open Boolean |
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| open Boolean |
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| open Boolean |
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| open Boolean |
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| open Boolean |
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| open E? |
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| open E? |
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| open E? |
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| open E? |
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| open E |
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| open E? |
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| open E |
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| open E? |
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| open E |
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| open E |
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| open Unit |
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| open Unit |
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| open Unit |
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| open Unit |
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| open Int |
Returns the number of additional elements that this deque can ideally (in the absence of memory or resource constraints) accept without blocking.
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| open E |
Retrieves and removes the head of the queue represented by this deque.
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| open Boolean |
Removes the first occurrence of the specified element from this deque.
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| open Boolean |
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| open E |
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| open Boolean |
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| open Boolean |
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| open E |
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| open Boolean |
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| open Boolean |
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| open Spliterator<E> |
Returns a Spliterator over the elements in this deque.
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| open E |
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| open E |
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| open E |
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| open Array<Any!> |
Returns an array containing all of the elements in this deque, in proper sequence (from first to last element).
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| open Array<T> |
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.
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| open String |
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| Properties |
| open Int |
Returns the number of elements in this deque.
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Public constructors
LinkedBlockingDeque
LinkedBlockingDeque()
Creates a LinkedBlockingDeque with a capacity of Integer.MAX_VALUE.
LinkedBlockingDeque
LinkedBlockingDeque(capacity: Int)
Creates a LinkedBlockingDeque with the given (fixed) capacity.
| Parameters |
capacity |
Int: the capacity of this deque |
| Exceptions |
java.lang.IllegalArgumentException |
if capacity is less than 1 |
LinkedBlockingDeque
LinkedBlockingDeque(c: MutableCollection<out E>!)
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.
| Parameters |
c |
MutableCollection<out E>!: the collection of elements to initially contain |
| Exceptions |
java.lang.NullPointerException |
if the specified collection or any of its elements are null |
Public methods
add
open fun add(element: E): Boolean
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(java.lang.Object).
This method is equivalent to #addLast.
| Parameters |
e |
the element to add |
| Exceptions |
java.lang.UnsupportedOperationException |
if the add operation is not supported by this collection |
java.lang.ClassCastException |
if the class of the specified element prevents it from being added to this deque |
java.lang.NullPointerException |
if the specified element is null |
java.lang.IllegalArgumentException |
if some property of the specified element prevents it from being added to this deque |
java.lang.IllegalStateException |
if this deque is full |
addAll
open fun addAll(elements: Collection<E>): Boolean
Appends all of the elements in the specified collection to the end of this deque, in the order that they are returned by the specified collection's iterator. Attempts to addAll of a deque to itself result in IllegalArgumentException.
| Parameters |
c |
the elements to be inserted into this deque |
| Return |
Boolean |
true if this deque changed as a result of the call |
| Exceptions |
java.lang.UnsupportedOperationException |
if the addAll operation is not supported by this collection |
java.lang.ClassCastException |
if the class of an element of the specified collection prevents it from being added to this deque |
java.lang.NullPointerException |
if the specified collection or any of its elements are null |
java.lang.IllegalArgumentException |
if the collection is this deque |
java.lang.IllegalStateException |
if this deque is full |
addFirst
open fun addFirst(e: E): Unit
| Parameters |
e |
E: the element to add |
| Exceptions |
java.lang.NullPointerException |
if the specified element is null |
java.lang.UnsupportedOperationException |
if this collection implementation does not support this operation |
java.lang.IllegalStateException |
if this deque is full |
java.lang.ClassCastException |
if the class of the specified element prevents it from being added to this deque |
java.lang.IllegalArgumentException |
if some property of the specified element prevents it from being added to this deque |
addLast
open fun addLast(e: E): Unit
| Parameters |
e |
E: the element to add |
| Exceptions |
java.lang.NullPointerException |
if the specified element is null |
java.lang.UnsupportedOperationException |
if this collection implementation does not support this operation |
java.lang.IllegalStateException |
if this deque is full |
java.lang.ClassCastException |
if the class of the specified element prevents it from being added to this deque |
java.lang.IllegalArgumentException |
if some property of the specified element prevents it from being added to this deque |
clear
open fun clear(): Unit
Atomically removes all of the elements from this deque. The deque will be empty after this call returns.
| Exceptions |
java.lang.UnsupportedOperationException |
if the clear operation is not supported by this collection |
contains
open fun contains(element: E?): Boolean
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).
| Parameters |
o |
object to be checked for containment in this deque |
| Return |
Boolean |
true if this deque contains the specified element |
| Exceptions |
java.lang.ClassCastException |
if the class of the specified element is incompatible with this deque (optional) |
java.lang.NullPointerException |
if the specified element is null (optional) |
descendingIterator
open fun descendingIterator(): MutableIterator<E>
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.
| Return |
MutableIterator<E> |
an iterator over the elements in this deque in reverse order |
drainTo
open fun drainTo(c: MutableCollection<in E>!): Int
| Return |
Int |
the number of elements transferred |
| Exceptions |
java.lang.UnsupportedOperationException |
if addition of elements is not supported by the specified collection |
java.lang.ClassCastException |
if the class of an element of this queue prevents it from being added to the specified collection |
java.lang.NullPointerException |
if the specified collection is null |
java.lang.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
open fun drainTo(
c: MutableCollection<in E>!,
maxElements: Int
): Int
| Parameters |
c |
MutableCollection<in E>!: the collection to transfer elements into |
maxElements |
Int: the maximum number of elements to transfer |
| Return |
Int |
the number of elements transferred |
| Exceptions |
java.lang.UnsupportedOperationException |
if addition of elements is not supported by the specified collection |
java.lang.ClassCastException |
if the class of an element of this queue prevents it from being added to the specified collection |
java.lang.NullPointerException |
if the specified collection is null |
java.lang.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 |
element
open fun element(): E
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().
| Return |
E |
the head of the queue represented by this deque |
| Exceptions |
java.util.NoSuchElementException |
if this deque is empty |
forEach
open fun forEach(action: Consumer<in E>): Unit
| Parameters |
action |
Consumer<in E>: The action to be performed for each element |
| Exceptions |
java.lang.NullPointerException |
if the specified action is null |
getFirst
open fun getFirst(): E
| Return |
E |
the head of this deque |
| Exceptions |
java.util.NoSuchElementException |
if this deque is empty |
getLast
open fun getLast(): E
| Return |
E |
the tail of this deque |
| Exceptions |
java.util.NoSuchElementException |
if this deque is empty |
iterator
open fun iterator(): MutableIterator<E>
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.
| Return |
MutableIterator<E> |
an iterator over the elements in this deque in proper sequence |
offer
open fun offer(e: E): Boolean
| Parameters |
e |
E: the element to add |
| Return |
Boolean |
true if the element was added to this queue, else false |
| Exceptions |
java.lang.ClassCastException |
if the class of the specified element prevents it from being added to this deque |
java.lang.NullPointerException |
if the specified element is null |
java.lang.IllegalArgumentException |
if some property of the specified element prevents it from being added to this deque |
offer
open fun offer(
e: E,
timeout: Long,
unit: TimeUnit!
): Boolean
| Parameters |
e |
E: the element to add |
timeout |
Long: how long to wait before giving up, in units of unit |
unit |
TimeUnit!: a TimeUnit determining how to interpret the timeout parameter |
| Return |
Boolean |
true if the element was added to this deque, else false |
| Exceptions |
java.lang.InterruptedException |
if interrupted while waiting |
java.lang.ClassCastException |
if the class of the specified element prevents it from being added to this deque |
java.lang.NullPointerException |
if the specified element is null |
java.lang.IllegalArgumentException |
if some property of the specified element prevents it from being added to this deque |
offerFirst
open fun offerFirst(e: E): Boolean
| Parameters |
e |
E: the element to add |
| Return |
Boolean |
true if the element was added to this deque, else false |
| Exceptions |
java.lang.ClassCastException |
if the class of the specified element prevents it from being added to this deque |
java.lang.NullPointerException |
if the specified element is null |
java.lang.IllegalArgumentException |
if some property of the specified element prevents it from being added to this deque |
offerFirst
open fun offerFirst(
e: E,
timeout: Long,
unit: TimeUnit!
): Boolean
| Parameters |
e |
E: the element to add |
timeout |
Long: how long to wait before giving up, in units of unit |
unit |
TimeUnit!: a TimeUnit determining how to interpret the timeout parameter |
| Return |
Boolean |
true if successful, or false if the specified waiting time elapses before space is available |
| Exceptions |
java.lang.InterruptedException |
if interrupted while waiting |
java.lang.ClassCastException |
if the class of the specified element prevents it from being added to this deque |
java.lang.NullPointerException |
if the specified element is null |
java.lang.IllegalArgumentException |
if some property of the specified element prevents it from being added to this deque |
offerLast
open fun offerLast(e: E): Boolean
| Parameters |
e |
E: the element to add |
| Return |
Boolean |
true if the element was added to this deque, else false |
| Exceptions |
java.lang.ClassCastException |
if the class of the specified element prevents it from being added to this deque |
java.lang.NullPointerException |
if the specified element is null |
java.lang.IllegalArgumentException |
if some property of the specified element prevents it from being added to this deque |
offerLast
open fun offerLast(
e: E,
timeout: Long,
unit: TimeUnit!
): Boolean
| Parameters |
e |
E: the element to add |
timeout |
Long: how long to wait before giving up, in units of unit |
unit |
TimeUnit!: a TimeUnit determining how to interpret the timeout parameter |
| Return |
Boolean |
true if successful, or false if the specified waiting time elapses before space is available |
| Exceptions |
java.lang.InterruptedException |
if interrupted while waiting |
java.lang.ClassCastException |
if the class of the specified element prevents it from being added to this deque |
java.lang.NullPointerException |
if the specified element is null |
java.lang.IllegalArgumentException |
if some property of the specified element prevents it from being added to this deque |
peek
open fun peek(): E?
| Return |
E? |
the head of this deque, or null if this deque is empty |
peekFirst
open fun peekFirst(): E?
| Return |
E? |
the head of this deque, or null if this deque is empty |
peekLast
open fun peekLast(): E?
| Return |
E? |
the tail of this deque, or null if this deque is empty |
poll
open fun poll(): E?
| Return |
E? |
the head of this deque, or null if this deque is empty |
poll
open fun poll(
timeout: Long,
unit: TimeUnit!
): E
| Parameters |
timeout |
Long: how long to wait before giving up, in units of unit |
unit |
TimeUnit!: a TimeUnit determining how to interpret the timeout parameter |
| Return |
E |
the head of this deque, or null if the specified waiting time elapses before an element is available |
| Exceptions |
java.lang.InterruptedException |
if interrupted while waiting |
pollFirst
open fun pollFirst(): E?
| Return |
E? |
the head of this deque, or null if this deque is empty |
pollFirst
open fun pollFirst(
timeout: Long,
unit: TimeUnit!
): E
| Parameters |
timeout |
Long: how long to wait before giving up, in units of unit |
unit |
TimeUnit!: a TimeUnit determining how to interpret the timeout parameter |
| Return |
E |
the head of this deque, or null if the specified waiting time elapses before an element is available |
| Exceptions |
java.lang.InterruptedException |
if interrupted while waiting |
pollLast
open fun pollLast(): E?
| Return |
E? |
the tail of this deque, or null if this deque is empty |
pollLast
open fun pollLast(
timeout: Long,
unit: TimeUnit!
): E
| Parameters |
timeout |
Long: how long to wait before giving up, in units of unit |
unit |
TimeUnit!: a TimeUnit determining how to interpret the timeout parameter |
| Return |
E |
the tail of this deque, or null if the specified waiting time elapses before an element is available |
| Exceptions |
java.lang.InterruptedException |
if interrupted while waiting |
pop
open fun pop(): E
| Return |
E |
the element at the front of this deque (which is the top of the stack represented by this deque) |
| Exceptions |
java.util.NoSuchElementException |
if this deque is empty |
push
open fun push(e: E): Unit
| Parameters |
e |
E: the element to push |
| Exceptions |
java.lang.IllegalStateException |
if this deque is full |
java.lang.ClassCastException |
if the class of the specified element prevents it from being added to this deque |
java.lang.NullPointerException |
if the specified element is null |
java.lang.IllegalArgumentException |
if some property of the specified element prevents it from being added to this deque |
put
open fun put(e: E): Unit
| Parameters |
e |
E: the element to add |
| Exceptions |
java.lang.InterruptedException |
if interrupted while waiting |
java.lang.ClassCastException |
if the class of the specified element prevents it from being added to this deque |
java.lang.NullPointerException |
if the specified element is null |
java.lang.IllegalArgumentException |
if some property of the specified element prevents it from being added to this deque |
putFirst
open fun putFirst(e: E): Unit
| Parameters |
e |
E: the element to add |
| Exceptions |
java.lang.InterruptedException |
if interrupted while waiting |
java.lang.ClassCastException |
if the class of the specified element prevents it from being added to this deque |
java.lang.NullPointerException |
if the specified element is null |
java.lang.IllegalArgumentException |
if some property of the specified element prevents it from being added to this deque |
putLast
open fun putLast(e: E): Unit
| Parameters |
e |
E: the element to add |
| Exceptions |
java.lang.InterruptedException |
if interrupted while waiting |
java.lang.ClassCastException |
if the class of the specified element prevents it from being added to this deque |
java.lang.NullPointerException |
if the specified element is null |
java.lang.IllegalArgumentException |
if some property of the specified element prevents it from being added to this deque |
remainingCapacity
open fun remainingCapacity(): Int
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.
| Return |
Int |
the remaining capacity |
remove
open fun remove(): E
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().
| Return |
E |
the head of the queue represented by this deque |
| Exceptions |
java.util.NoSuchElementException |
if this deque is empty |
remove
open fun remove(element: E?): Boolean
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(java.lang.Object).
| Parameters |
o |
element to be removed from this deque, if present |
| Return |
Boolean |
true if this deque changed as a result of the call |
| Exceptions |
java.lang.ClassCastException |
if the class of the specified element is incompatible with this deque (optional) |
java.lang.NullPointerException |
if the specified element is null (optional) |
java.lang.UnsupportedOperationException |
if the remove operation is not supported by this collection |
removeAll
open fun removeAll(elements: Collection<E>): Boolean
| Parameters |
c |
collection containing elements to be removed from this collection |
| Return |
Boolean |
true if this collection changed as a result of the call |
| Exceptions |
java.lang.UnsupportedOperationException |
if the removeAll method is not supported by this collection |
java.lang.ClassCastException |
if the types of one or more elements in this collection are incompatible with the specified collection (java.util.Collection#) |
java.lang.NullPointerException |
if this collection contains one or more null elements and the specified collection does not support null elements (java.util.Collection#) or if the specified collection is null |
removeFirst
open fun removeFirst(): E
| Return |
E |
the head of this deque |
| Exceptions |
java.util.NoSuchElementException |
if this deque is empty |
java.lang.UnsupportedOperationException |
if this collection implementation does not support this operation |
removeFirstOccurrence
open fun removeFirstOccurrence(o: Any?): Boolean
| Parameters |
o |
Any?: element to be removed from this deque, if present |
| Return |
Boolean |
true if an element was removed as a result of this call |
| Exceptions |
java.lang.ClassCastException |
if the class of the specified element is incompatible with this deque (optional) |
java.lang.NullPointerException |
if the specified element is null (optional) |
removeIf
open fun removeIf(filter: Predicate<in E>): Boolean
| Parameters |
filter |
Predicate<in E>: a predicate which returns true for elements to be removed |
| Return |
Boolean |
true if any elements were removed |
| Exceptions |
java.lang.NullPointerException |
if the specified filter is null |
java.lang.UnsupportedOperationException |
if elements cannot be removed from this collection. Implementations may throw this exception if a matching element cannot be removed or if, in general, removal is not supported. |
removeLast
open fun removeLast(): E
| Return |
E |
the tail of this deque |
| Exceptions |
java.util.NoSuchElementException |
if this deque is empty |
java.lang.UnsupportedOperationException |
if this collection implementation does not support this operation |
removeLastOccurrence
open fun removeLastOccurrence(o: Any?): Boolean
| Parameters |
o |
Any?: element to be removed from this deque, if present |
| Return |
Boolean |
true if an element was removed as a result of this call |
| Exceptions |
java.lang.ClassCastException |
if the class of the specified element is incompatible with this deque (optional) |
java.lang.NullPointerException |
if the specified element is null (optional) |
retainAll
open fun retainAll(elements: Collection<E>): Boolean
| Parameters |
c |
collection containing elements to be retained in this collection |
| Return |
Boolean |
true if this collection changed as a result of the call |
| Exceptions |
java.lang.UnsupportedOperationException |
if the retainAll operation is not supported by this collection |
java.lang.ClassCastException |
if the types of one or more elements in this collection are incompatible with the specified collection (java.util.Collection#) |
java.lang.NullPointerException |
if this collection contains one or more null elements and the specified collection does not permit null elements (java.util.Collection#) or if the specified collection is null |
take
open fun take(): E
| Return |
E |
the head of this deque |
| Exceptions |
java.lang.InterruptedException |
if interrupted while waiting |
takeFirst
open fun takeFirst(): E
| Return |
E |
the head of this deque |
| Exceptions |
java.lang.InterruptedException |
if interrupted while waiting |
takeLast
open fun takeLast(): E
| Return |
E |
the tail of this deque |
| Exceptions |
java.lang.InterruptedException |
if interrupted while waiting |
toArray
open fun toArray(): Array<Any!>
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.
| Return |
Array<Any!> |
an array containing all of the elements in this deque |
toArray
open fun <T : Any!> toArray(a: Array<T>): Array<T>
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:
<code>String[] y = x.toArray(new String[0]);</code>
Note that
toArray(new Object[0]) is identical in function to
toArray().
| Parameters |
<T> |
the component type of the array to contain the collection |
a |
Array<T>: 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 |
| Return |
Array<T> |
an array containing all of the elements in this deque |
| Exceptions |
java.lang.ArrayStoreException |
if the runtime type of the specified array is not a supertype of the runtime type of every element in this deque |
java.lang.NullPointerException |
if the specified array is null |
toString
open fun toString(): String
| Return |
String |
a string representation of the object. |
Properties
size
open val size: Int
Returns the number of elements in this deque.
| Return |
Int |
the number of elements in this deque |
