Package it.unimi.dsi.fastutil.longs

Class LongArrayFIFOQueue

java.lang.Object
it.unimi.dsi.fastutil.longs.LongArrayFIFOQueue
All Implemented Interfaces:
LongPriorityQueue, PriorityQueue<Long>, Serializable
public class LongArrayFIFOQueue extends Object implements LongPriorityQueue, Serializable
A type-specific array-based FIFO queue, supporting also deque operations.

Instances of this class represent a FIFO queue using a backing array in a circular way. The array is enlarged and shrunk as needed. You can use the trim() method to reduce its memory usage, if necessary.

This class provides additional methods that implement a deque (double-ended queue).

See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    INITIAL_CAPACITY
    The standard initial capacity of a queue.

  • Constructor Summary

    Constructors
    Constructor
    Description
    LongArrayFIFOQueue()
    Creates a new empty queue with standard initial capacity.
    LongArrayFIFOQueue(int capacity)
    Creates a new empty queue with given capacity.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    clear()
    Removes all elements from this queue.
    LongComparator
    comparator()
    Returns the comparator associated with this priority queue, or null if it uses its elements' natural ordering.
    long
    dequeueLastLong()
    Dequeues the last element from the queue.
    long
    dequeueLong()
    Dequeues the first element from the queue.
    void
    enqueue(long x)
    Enqueues a new element.
    void
    enqueueFirst(long x)
    Enqueues a new element as the first element (in dequeuing order) of the queue.
    long
    firstLong()
    Returns the first element of the queue.
    long
    lastLong()
    Returns the last element of the queue, that is, the element the would be dequeued last (optional operation).
    int
    size()
    Returns the number of elements in this queue.
    void
    trim()
    Trims the queue to the smallest possible size.

    Methods inherited from class java.lang.Object

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

    Methods inherited from interface it.unimi.dsi.fastutil.longs.LongPriorityQueue

    dequeue, enqueue, first, last

    Methods inherited from interface it.unimi.dsi.fastutil.PriorityQueue

    changed, isEmpty

  • Field Details

    • INITIAL_CAPACITY

      public static final int INITIAL_CAPACITY
      The standard initial capacity of a queue.
      See Also:

  • Constructor Details

    • LongArrayFIFOQueue

      public LongArrayFIFOQueue(int capacity)
      Creates a new empty queue with given capacity.
      Parameters:
      capacity - the initial capacity of this queue.
      Implementation Notes:
      Because of inner limitations of the JVM, the initial capacity cannot exceed Arrays.MAX_ARRAY_SIZE − 1.

    • LongArrayFIFOQueue

      public LongArrayFIFOQueue()
      Creates a new empty queue with standard initial capacity.

  • Method Details