it.unimi.dsi.fastutil.longs
Class LongArrayFIFOQueue

java.lang.Object
  extended by it.unimi.dsi.fastutil.AbstractPriorityQueue<Long>
      extended by it.unimi.dsi.fastutil.longs.AbstractLongPriorityQueue
          extended by it.unimi.dsi.fastutil.longs.LongArrayFIFOQueue
All Implemented Interfaces:
LongPriorityQueue, PriorityQueue<Long>

public class LongArrayFIFOQueue
extends AbstractLongPriorityQueue

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 as needed, but it is never shrunk. Use the trim() method to reduce its size, if necessary.

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


Field Summary
static int INITIAL_CAPACITY
          The standard initial capacity of a queue.
 
Constructor Summary
LongArrayFIFOQueue()
          Creates a new empty queue with standard initial capacity.
LongArrayFIFOQueue(int capacity)
          Creates a new empty queue with given capacity.
 
Method Summary
 void clear()
          Removes all elements from this queue.
 LongComparator comparator()
          Returns null (FIFO queues have no comparator).
 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.
 int size()
          Returns the number of elements in this queue.
 void trim()
          Trims the queue to the smallest possible size.
 
Methods inherited from class it.unimi.dsi.fastutil.longs.AbstractLongPriorityQueue
dequeue, enqueue, first, last
 
Methods inherited from class it.unimi.dsi.fastutil.AbstractPriorityQueue
changed, isEmpty
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface it.unimi.dsi.fastutil.PriorityQueue
changed, isEmpty
 

Field Detail

INITIAL_CAPACITY

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

See Also:
Constant Field Values
Constructor Detail

LongArrayFIFOQueue

public LongArrayFIFOQueue(int capacity)
Creates a new empty queue with given capacity.

Parameters:
capacity - the initial capacity of this queue.

LongArrayFIFOQueue

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

Method Detail

comparator

public LongComparator comparator()
Returns null (FIFO queues have no comparator).

Returns:
null.
See Also:
PriorityQueue.comparator()

dequeueLong

public long dequeueLong()
Description copied from interface: LongPriorityQueue
Dequeues the first element from the queue.

Returns:
the dequeued element.

dequeueLastLong

public long dequeueLastLong()
Dequeues the last element from the queue.

Returns:
the dequeued element.
Throws:
NoSuchElementException - if the queue is empty.

enqueue

public void enqueue(long x)
Description copied from interface: LongPriorityQueue
Enqueues a new element.

Parameters:
x - the element to enqueue.

enqueueFirst

public void enqueueFirst(long x)
Enqueues a new element as the first element (in dequeuing order) of the queue.


firstLong

public long firstLong()
Returns the first element of the queue.

Returns:
the first element of the queue.

lastLong

public long lastLong()
Returns the last element of the queue.

Specified by:
lastLong in interface LongPriorityQueue
Overrides:
lastLong in class AbstractLongPriorityQueue
Returns:
the last element of the queue.

clear

public void clear()
Description copied from interface: PriorityQueue
Removes all elements from this queue.


trim

public void trim()
Trims the queue to the smallest possible size.


size

public int size()
Description copied from interface: PriorityQueue
Returns the number of elements in this queue.

Returns:
the number of elements in this queue.