| java.lang.Object | |||
| ↳ | java.util.AbstractCollection<E> | ||
| ↳ | java.util.AbstractQueue<E> | ||
| ↳ | java.util.concurrent.ArrayBlockingQueue<E> | ||
A bounded blocking queue backed by an array. This queue orders elements FIFO (first-in-first-out). The head of the queue is that element that has been on the queue the longest time. The tail of the queue is that element that has been on the queue the shortest time. New elements are inserted at the tail of the queue, and the queue retrieval operations obtain elements at the head of the queue.
This is a classic "bounded buffer", in which a fixed-sized array holds elements inserted by producers and extracted by consumers. Once created, the capacity cannot be increased. Attempts to offer an element to a full queue will result in the offer operation blocking; attempts to retrieve an element from an empty queue will similarly block.
This class supports an optional fairness policy for ordering waiting producer and consumer threads. By default, this ordering is not guaranteed. However, a queue constructed with fairness set to true grants threads access in FIFO order. Fairness generally decreases throughput but reduces variability and avoids starvation.
This class implements all of the optional methods of the Collection and Iterator interfaces.
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Creates an ArrayBlockingQueue with the given (fixed)
capacity and default access policy.
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Creates an ArrayBlockingQueue with the given (fixed)
capacity and the specified access policy.
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Creates an ArrayBlockingQueue with the given (fixed)
capacity, the specified access policy and initially containing the
elements of the given collection,
added in traversal order of the collection's iterator.
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| Public Methods | |||||||||||
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Removes all elements of the queue.
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Searches this Collection for the specified object.
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Removes at most the given number of available elements from
this queue and adds them into the given collection.
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Removes all available elements from this queue and adds them
into the given collection.
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Returns an iterator over the elements in this queue in proper sequence.
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Inserts the specified element at the tail of this queue, waiting if
necessary up to the specified wait time for space to become available.
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Inserts the specified element at the tail of this queue if possible,
returning immediately if this queue is full.
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Gets but not removes the element in the head of the queue, or throws
exception if there is no element in the queue.
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Retrieves and removes the head of this queue, waiting
if necessary up to the specified wait time if no elements are
present on this queue.
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Gets and removes the element in the head of the queue, or returns null if
there is no element in the queue.
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Adds the specified element to the tail of this queue, waiting if
necessary for space to become available.
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Returns the number of elements that this queue can ideally (in
the absence of memory or resource constraints) accept without
blocking.
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Removes the first occurrence of the specified object from this
Collection.
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Returns the number of elements in this queue.
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Retrieves and removes the head of this queue, waiting
if no elements are present on this queue.
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Returns an array containing all elements contained in this Collection.
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Returns a new array containing all elements contained in this Collection.
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Returns the string representation of this Collection.
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[Expand]
Inherited Methods | |||||||||||
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From class java.util.AbstractQueue
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From class java.util.AbstractCollection
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From class java.lang.Object
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From interface java.lang.Iterable
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From interface java.util.Collection
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From interface java.util.Queue
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From interface java.util.concurrent.BlockingQueue
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Creates an ArrayBlockingQueue with the given (fixed) capacity and default access policy.
| capacity | the capacity of this queue |
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| IllegalArgumentException | if capacity is less than 1 |
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Creates an ArrayBlockingQueue with the given (fixed) capacity and the specified access policy.
| capacity | the capacity of this queue |
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| fair | if true then queue accesses for threads blocked on insertion or removal, are processed in FIFO order; if false the access order is unspecified. |
| IllegalArgumentException | if capacity is less than 1 |
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Creates an ArrayBlockingQueue with the given (fixed) capacity, the specified access policy and initially containing the elements of the given collection, added in traversal order of the collection's iterator.
| capacity | the capacity of this queue |
|---|---|
| fair | if true then queue accesses for threads blocked on insertion or removal, are processed in FIFO order; if false the access order is unspecified. |
| c | the collection of elements to initially contain |
| IllegalArgumentException | if capacity is less than c.size(), or less than 1. |
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| NullPointerException | if c or any element within it is null |
Removes all elements of the queue.
Searches this Collection for the specified object.
| o | the object to search for |
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object is an element of this Collection,
false otherwise
Removes at most the given number of available elements from this queue and adds them into 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.
| c | the collection to transfer elements into |
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| maxElements | the maximum number of elements to transfer |
Removes all available elements from this queue and adds them into 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.
| c | the collection to transfer elements into |
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Returns an iterator over the elements in this queue in proper sequence. 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.
Inserts the specified element at the tail of this queue, waiting if necessary up to the specified wait time for space to become available.
| o | the element to add |
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| timeout | how long to wait before giving up, in units of unit |
| unit | a TimeUnit determining how to interpret the timeout parameter |
| InterruptedException | if interrupted while waiting. |
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| NullPointerException | if the specified element is null. |
Inserts the specified element at the tail of this queue if possible, returning immediately if this queue is full.
| o | the element to add. |
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| NullPointerException | if the specified element is null |
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Gets but not removes the element in the head of the queue, or throws exception if there is no element in the queue.
Retrieves and removes the head of this queue, waiting if necessary up to the specified wait time if no elements are present on this queue.
| timeout | how long to wait before giving up, in units of unit |
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| unit | a TimeUnit determining how to interpret the timeout parameter |
| InterruptedException |
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Gets and removes the element in the head of the queue, or returns null if there is no element in the queue.
Adds the specified element to the tail of this queue, waiting if necessary for space to become available.
| o | the element to add |
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| InterruptedException | if interrupted while waiting. |
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| NullPointerException | if the specified element is null. |
Returns the number of elements that this queue can ideally (in the absence of memory or resource constraints) accept without blocking. This is always equal to the initial capacity of this queue less the current size of this queue.
Note that you cannot always tell if an attempt to add an element will succeed by inspecting remainingCapacity because it may be the case that a waiting consumer is ready to take an element out of an otherwise full queue.
Removes the first occurrence of the specified object from this Collection. This operation traverses over the collection, looking for the specified object. Once the object is found, the object will be removed from the collection using the iterator's remove method. This collection will throw an UnsupportedOperationException if the iterator returned does not implement remove method, and the specified object is in this collection.
| o | the object to remove |
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Returns the number of elements in this queue.
Retrieves and removes the head of this queue, waiting if no elements are present on this queue.
| InterruptedException |
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Returns an array containing all elements contained in this Collection. If the specified array is large enough to hold the elements, the specified array is used, otherwise an array of the same type is created. If the specified array is used and is larger than this Collection, the array element following the collection elements is set to null.
| a | the array |
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Returns a new array containing all elements contained in this Collection. All the elements in the array will not be referenced by the collection. The elements in the returned array will be sorted to the same order as those returned by the iterator of this collection itself if the collection guarantees the order.
Returns the string representation of this Collection. The presentation has a specific format. It is enclosed by square brackets ("[]"). Elements are separated by ', ' (comma and space).