Class SynchronizedQueue<T>

java.lang.Object
org.apache.tomcat.util.collections.SynchronizedQueue<T>
Type Parameters:
T - The type of object managed by this queue
public class SynchronizedQueue<T> extends Object
This is intended as a (mostly) GC-free alternative to ConcurrentLinkedQueue when the requirement is to create an unbounded queue with no requirement to shrink the queue. The aim is to provide the bare minimum of required functionality as quickly as possible with minimum garbage.

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    DEFAULT_SIZE
    The default initial capacity for a new queue.

  • Constructor Summary

    Constructors
    Constructor
    Description
    SynchronizedQueue()
    Constructs a new SynchronizedQueue with the default initial capacity.
    SynchronizedQueue(int initialSize)
    Constructs a new SynchronizedQueue with the specified initial capacity.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    clear()
    Removes all elements from this queue.
    boolean
    offer(T t)
    Adds the specified element to the tail of this queue.
    T
    poll()
    Retrieves and removes the head of this queue, or returns null if this queue is empty.
    int
    size()
    Returns the number of elements in this queue.

    Methods inherited from class Object

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

  • Field Details

    • DEFAULT_SIZE

      public static final int DEFAULT_SIZE
      The default initial capacity for a new queue.
      See Also:

  • Constructor Details

    • SynchronizedQueue

      public SynchronizedQueue()
      Constructs a new SynchronizedQueue with the default initial capacity.

    • SynchronizedQueue

      public SynchronizedQueue(int initialSize)
      Constructs a new SynchronizedQueue with the specified initial capacity.
      Parameters:
      initialSize - the initial capacity

  • Method Details

    • offer

      public boolean offer(T t)
      Adds the specified element to the tail of this queue.
      Parameters:
      t - the element to add
      Returns:
      true (as specified by Queue.offer(E))

    • poll

      public T poll()
      Retrieves and removes the head of this queue, or returns null if this queue is empty.
      Returns:
      the head of this queue, or null if empty

    • size

      public int size()
      Returns the number of elements in this queue.
      Returns:
      the number of elements

    • clear

      public void clear()
      Removes all elements from this queue.