程序包 org.dromara.dynamictp.common.queue

类 VariableLinkedBlockingQueue<E>

java.lang.Object
java.util.AbstractCollection<E>
java.util.AbstractQueue<E>
org.dromara.dynamictp.common.queue.VariableLinkedBlockingQueue<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>, BlockingQueue<E>, Queue<E>
直接已知子类:
MemorySafeLinkedBlockingQueue
public class VariableLinkedBlockingQueue<E> extends AbstractQueue<E> implements BlockingQueue<E>, Serializable
A clone of LinkedBlockingQueue with the addition of a setCapacity(int) method, allowing us to change the capacity of the queue while it is in use.

The documentation for LinkedBlockingQueue follows...

An optionally-bounded blocking queue based on linked nodes. 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. Linked queues typically have higher throughput than array-based queues but less predictable performance in most concurrent applications.

The optional capacity bound constructor argument serves as a way to prevent excessive queue expansion. The capacity, if unspecified, is equal to Integer.MAX_VALUE. Linked nodes are dynamically created upon each insertion unless this would bring the queue above capacity.

This class implements 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:
1.5
作者:
Doug Lea
另请参阅:

  • 构造器详细资料

    • VariableLinkedBlockingQueue

      public VariableLinkedBlockingQueue()
      Creates a VariableLinkedBlockingQueue with a capacity of Integer.MAX_VALUE.

    • VariableLinkedBlockingQueue

      public VariableLinkedBlockingQueue(int capacity)
      Creates a VariableLinkedBlockingQueue with the given (fixed) capacity.
      参数:
      capacity - the capacity of this queue
      抛出:
      IllegalArgumentException - if capacity is not greater than zero

    • VariableLinkedBlockingQueue

      public VariableLinkedBlockingQueue(Collection<? extends E> c)
      Creates a VariableLinkedBlockingQueue 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

    • size

      public int size()
      Returns the number of elements in this queue.
      指定者:
      size 在接口中 Collection<E>
      指定者:
      size 在类中 AbstractCollection<E>
      返回:
      the number of elements in this queue

    • setCapacity

      public void setCapacity(int capacity)
      Set a new capacity for the queue. Increasing the capacity can cause any waiting put(Object) invocations to succeed if the new capacity is larger than the queue.
      参数:
      capacity - the new capacity for the queue

    • remainingCapacity

      public int remainingCapacity()
      Returns the number of additional 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 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>

    • put

      public void put(E e) throws InterruptedException
      Inserts the specified element at the tail of this queue, waiting if necessary for space to become available.
      指定者:
      put 在接口中 BlockingQueue<E>
      抛出:
      InterruptedException
      NullPointerException

    • offer

      public boolean offer(E e, long timeout, TimeUnit unit) throws InterruptedException
      Inserts the specified element at the tail of this queue, waiting if necessary up to the specified wait time for space to become available.
      指定者:
      offer 在接口中 BlockingQueue<E>
      返回:
      true if successful, or false if the specified waiting time elapses before space is available
      抛出:
      InterruptedException
      NullPointerException

    • offer

      public boolean offer(E e)
      Inserts the specified element at the tail of this queue if it is possible to do so immediately without exceeding the queue's capacity, returning true upon success and false if this queue is full. When using a capacity-restricted queue, this method is generally preferable to method add, which can fail to insert an element only by throwing an exception.
      指定者:
      offer 在接口中 BlockingQueue<E>
      指定者:
      offer 在接口中 Queue<E>
      抛出:
      NullPointerException - if the specified element is null

    • take

      public E take() throws InterruptedException
      指定者:
      take 在接口中 BlockingQueue<E>
      抛出:
      InterruptedException

    • poll

      public E poll(long timeout, TimeUnit unit) throws InterruptedException
      指定者:
      poll 在接口中 BlockingQueue<E>
      抛出:
      InterruptedException

    • poll

      public E poll()
      指定者:
      poll 在接口中 Queue<E>

    • peek

      public E peek()
      指定者:
      peek 在接口中 Queue<E>

    • remove

      public boolean remove(Object o)
      Removes a single instance of the specified element from this queue, if it is present. More formally, removes an element e such that o.equals(e), if this queue contains one or more such elements. Returns true if this queue contained the specified element (or equivalently, if this queue changed as a result of the call).
      指定者:
      remove 在接口中 BlockingQueue<E>
      指定者:
      remove 在接口中 Collection<E>
      覆盖:
      remove 在类中 AbstractCollection<E>
      参数:
      o - element to be removed from this queue, if present
      返回:
      true if this queue changed as a result of the call

    • contains

      public boolean contains(Object o)
      Returns true if this queue contains the specified element. More formally, returns true if and only if this queue contains at least one element e such that o.equals(e).
      指定者:
      contains 在接口中 BlockingQueue<E>
      指定者:
      contains 在接口中 Collection<E>
      覆盖:
      contains 在类中 AbstractCollection<E>
      参数:
      o - object to be checked for containment in this queue
      返回:
      true if this queue contains the specified element

    • toArray

      public Object[] toArray()
      Returns an array containing all of the elements in this queue, in proper sequence.

      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.

      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 queue

    • toArray

      public <T> T[] toArray(T[] a)
      Returns an array containing all of the elements in this queue, in proper sequence; the runtime type of the returned array is that of the specified array. 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.

      Suppose x is a queue known to contain only strings. The following code can be used to dump the queue 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>
      参数:
      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
      返回:
      an array containing all of the elements in this queue
      抛出:
      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

    • toString

      public String toString()
      覆盖:
      toString 在类中 AbstractCollection<E>

    • clear

      public void clear()
      Atomically removes all of the elements from this queue. The queue 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>

    • drainTo

      public int drainTo(Collection<? super E> c)
      指定者:
      drainTo 在接口中 BlockingQueue<E>
      抛出:
      UnsupportedOperationException
      ClassCastException
      NullPointerException
      IllegalArgumentException

    • drainTo

      public int drainTo(Collection<? super E> c, int maxElements)
      指定者:
      drainTo 在接口中 BlockingQueue<E>
      抛出:
      UnsupportedOperationException
      ClassCastException
      NullPointerException
      IllegalArgumentException

    • iterator

      public Iterator<E> iterator()
      Returns an iterator over the elements in this queue 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 Collection<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 queue in proper sequence

    • spliterator

      public Spliterator<E> spliterator()
      Returns a Spliterator over the elements in this queue.

      The returned spliterator is weakly consistent.

      The Spliterator reports Spliterator.CONCURRENT, Spliterator.ORDERED, and Spliterator.NONNULL. The Spliterator implements trySplit to permit limited parallelism.

      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 queue
      从以下版本开始:
      1.8