E - the type of elements held in this queue
Iterable<E>, Collection<E>, BlockingQueue<E>, Queue<E>
An unbounded
blocking queueof
Delayed
elements, in which an element can only be taken when its delay has expired. The
headof the queue is that
Delayed
element whose delay expired furthest in the past. If no delay has expired there is no head and
poll
will return
null
. Expiration occurs when an element's
getDelay(TimeUnit.NANOSECONDS)
method returns a value less than or equal to zero. Even though unexpired elements cannot be removed using
take
or
poll
, they are otherwise treated as normal elements. For example, the
size
method returns the count of both expired and unexpired elements. This queue does not permit null elements.
This class and its iterator implement all of the optional methods of the Collection and Iterator interfaces. The Iterator provided in method iterator() is not guaranteed to traverse the elements of the DelayQueue in any particular order.
This class is a member of the Java Collections Framework.
Constructors
Creates a new DelayQueue that is initially empty.
Creates a
DelayQueue
initially containing the elements of the given collection of
Delayed
instances.
boolean
Inserts the specified element into this delay queue.
void
Atomically removes all of the elements from this delay queue.
int
Removes all available elements from this queue and adds them to the given collection.
int
Removes at most the given number of available elements from this queue and adds them to the given collection.
Returns an iterator over all the elements (both expired and unexpired) in this queue.
boolean
Inserts the specified element into this delay queue.
boolean
Inserts the specified element into this delay queue.
Retrieves, but does not remove, the head of this queue, or returns null if this queue is empty.
Retrieves and removes the head of this queue, or returns null if this queue has no elements with an expired delay.
Retrieves and removes the head of this queue, waiting if necessary until an element with an expired delay is available on this queue, or the specified wait time expires.
void
Inserts the specified element into this delay queue.
int
Always returns Integer.MAX_VALUE because a DelayQueue is not capacity constrained.
boolean
Removes a single instance of the specified element from this queue, if it is present, whether or not it has expired.
int
Returns the number of elements in this collection.
Retrieves and removes the head of this queue, waiting if necessary until an element with an expired delay is available on this queue.
Returns an array containing all of the elements in this queue.
<T> T[]
Returns an array containing all of the elements in this queue; the runtime type of the returned array is that of the specified array.
Methods declared in interface java.util.CollectionaddAll, containsAll, equals, hashCode, isEmpty, parallelStream, removeAll, removeIf, retainAll, spliterator, stream, toArraypublic DelayQueue()
Creates a new DelayQueue that is initially empty.
Creates a
DelayQueue
initially containing the elements of the given collection of
Delayed
instances.
c - the collection of elements to initially contain
NullPointerException - if the specified collection or any of its elements are null
Inserts the specified element into this delay queue.
add in interface BlockingQueue<E extends Delayed>
add in interface Collection<E extends Delayed>
add in interface Queue<E extends Delayed>
add in class AbstractQueue<E extends Delayed>
e - the element to add
true (as specified by Collection.add(E))
NullPointerException - if the specified element is null
Inserts the specified element into this delay queue.
offer in interface BlockingQueue<E extends Delayed>
offer in interface Queue<E extends Delayed>
e - the element to add
true
NullPointerException - if the specified element is null
Inserts the specified element into this delay queue. As the queue is unbounded this method will never block.
put in interface BlockingQueue<E extends Delayed>
e - the element to add
NullPointerException - if the specified element is null
Inserts the specified element into this delay queue. As the queue is unbounded this method will never block.
offer in interface BlockingQueue<E extends Delayed>
e - the element to add
timeout - This parameter is ignored as the method never blocks
unit - This parameter is ignored as the method never blocks
true
NullPointerException - if the specified element is null
Retrieves and removes the head of this queue, or returns null if this queue has no elements with an expired delay.
Retrieves and removes the head of this queue, waiting if necessary until an element with an expired delay is available on this queue.
take in interface BlockingQueue<E extends Delayed>
InterruptedException - if interrupted while waiting
Retrieves and removes the head of this queue, waiting if necessary until an element with an expired delay is available on this queue, or the specified wait time expires.
poll in interface BlockingQueue<E extends Delayed>
timeout - how long to wait before giving up, in units of unit
unit - a TimeUnit determining how to interpret the timeout parameter
null if the specified waiting time elapses before an element with an expired delay becomes available
InterruptedException - if interrupted while waiting
Retrieves, but does not remove, the head of this queue, or returns null if this queue is empty. Unlike poll, if no expired elements are available in the queue, this method returns the element that will expire next, if one exists.
public int size()
Returns the number of elements in this collection. If this collection contains more than Integer.MAX_VALUE elements, returns Integer.MAX_VALUE.
size in interface Collection<E extends Delayed>
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.
drainTo in interface BlockingQueue<E extends Delayed>
c - the collection to transfer elements into
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
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.
drainTo in interface BlockingQueue<E extends Delayed>
c - the collection to transfer elements into
maxElements - the maximum number of elements to transfer
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
public void clear()
Atomically removes all of the elements from this delay queue. The queue will be empty after this call returns. Elements with an unexpired delay are not waited for; they are simply discarded from the queue.
clear in interface Collection<E extends Delayed>
clear in class AbstractQueue<E extends Delayed>
public int remainingCapacity()
Always returns Integer.MAX_VALUE because a DelayQueue is not capacity constrained.
remainingCapacity in interface BlockingQueue<E extends Delayed>
Integer.MAX_VALUE
Returns an array containing all of the elements in this queue. The returned array elements are in no particular order.
The returned array will be "safe" in that no references to it are maintained by this queue. (In other words, this method must allocate a new array). The caller is thus free to modify the returned array.
This method acts as bridge between array-based and collection-based APIs.
toArray in interface Collection<E extends Delayed>
toArray in class AbstractCollection<E extends Delayed>
public <T> T[] toArray(T[] a)
Returns an array containing all of the elements in this queue; the runtime type of the returned array is that of the specified array. The returned array elements are in no particular order. If the queue fits in the specified array, it is returned therein. Otherwise, a new array is allocated with the runtime type of the specified array and the size of this queue.
If this queue fits in the specified array with room to spare (i.e., the array has more elements than this queue), the element in the array immediately following the end of the queue is set to null.
Like the toArray() method, this method acts as bridge between array-based and collection-based APIs. Further, this method allows precise control over the runtime type of the output array, and may, under certain circumstances, be used to save allocation costs.
The following code can be used to dump a delay queue into a newly allocated array of Delayed:
Delayed[] a = q.toArray(new Delayed[0]);
Note that
toArray(new Object[0])
is identical in function to
toArray()
.
toArray in interface Collection<E extends Delayed>
toArray in class AbstractCollection<E extends Delayed>
T - the component type of the array to contain the collection
a - the array into which the elements of the queue are to be stored, if it is big enough; otherwise, a new array of the same runtime type is allocated for this purpose
ArrayStoreException - if the runtime type of the specified array is not a supertype of the runtime type of every element in this queue
NullPointerException - if the specified array is null
Removes a single instance of the specified element from this queue, if it is present, whether or not it has expired.
remove in interface BlockingQueue<E extends Delayed>
remove in interface Collection<E extends Delayed>
remove in class AbstractCollection<E extends Delayed>
o - element to be removed from this collection, if present
true if an element was removed as a result of this call
The returned iterator is weakly consistent.
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4