Package it.unimi.dsi.fastutil.chars

Class CharArrayPriorityQueue

java.lang.Object
it.unimi.dsi.fastutil.chars.CharArrayPriorityQueue
All Implemented Interfaces:
CharPriorityQueue, it.unimi.dsi.fastutil.PriorityQueue<java.lang.Character>, java.io.Serializable
public class CharArrayPriorityQueue
extends java.lang.Object
implements CharPriorityQueue, java.io.Serializable
A type-specific array-based priority queue.

Instances of this class represent a priority queue using a backing array—all operations are performed directly on the array. The array is enlarged as needed, but it is never shrunk. Use the trim() method to reduce its size, if necessary.

See Also:
Serialized Form
Implementation Specification:
This implementation is extremely inefficient, but it is difficult to beat when the size of the queue is very small.

  • Constructor Details

    • CharArrayPriorityQueue

      public CharArrayPriorityQueue​(int capacity, CharComparator c)
      Creates a new empty queue with a given capacity and comparator.
      Parameters:
      capacity - the initial capacity of this queue.
      c - the comparator used in this queue, or null for the natural order.

    • CharArrayPriorityQueue

      public CharArrayPriorityQueue​(int capacity)
      Creates a new empty queue with a given capacity and using the natural order.
      Parameters:
      capacity - the initial capacity of this queue.

    • CharArrayPriorityQueue

      public CharArrayPriorityQueue​(CharComparator c)
      Creates a new empty queue with a given comparator.
      Parameters:
      c - the comparator used in this queue, or null for the natural order.

    • CharArrayPriorityQueue

      public CharArrayPriorityQueue()
      Creates a new empty queue using the natural order.

    • CharArrayPriorityQueue

      public CharArrayPriorityQueue​(char[] a, int size, CharComparator c)
      Wraps a given array in a queue using a given comparator.

      The queue returned by this method will be backed by the given array.

      Parameters:
      a - an array.
      size - the number of elements to be included in the queue.
      c - the comparator used in this queue, or null for the natural order.

    • CharArrayPriorityQueue

      public CharArrayPriorityQueue​(char[] a, CharComparator c)
      Wraps a given array in a queue using a given comparator.

      The queue returned by this method will be backed by the given array.

      Parameters:
      a - an array.
      c - the comparator used in this queue, or null for the natural order.

    • CharArrayPriorityQueue

      public CharArrayPriorityQueue​(char[] a, int size)
      Wraps a given array in a queue using the natural order.

      The queue returned by this method will be backed by the given array.

      Parameters:
      a - an array.
      size - the number of elements to be included in the queue.

    • CharArrayPriorityQueue

      public CharArrayPriorityQueue​(char[] a)
      Wraps a given array in a queue using the natural order.

      The queue returned by this method will be backed by the given array.

      Parameters:
      a - an array.

  • Method Details

    • enqueue

      public void enqueue​(char x)
      Description copied from interface: CharPriorityQueue
      Enqueues a new element.
      Specified by:
      enqueue in interface CharPriorityQueue
      Parameters:
      x - the element to enqueue.
      See Also:
      PriorityQueue.enqueue(Object)

    • dequeueChar

      public char dequeueChar()
      Description copied from interface: CharPriorityQueue
      Dequeues the first element from the queue.
      Specified by:
      dequeueChar in interface CharPriorityQueue
      Returns:
      the dequeued element.
      See Also:
      CharPriorityQueue.dequeue()

    • firstChar

      public char firstChar()
      Description copied from interface: CharPriorityQueue
      Returns the first element of the queue.
      Specified by:
      firstChar in interface CharPriorityQueue
      Returns:
      the first element.
      See Also:
      CharPriorityQueue.first()

    • changed

      public void changed()
      Specified by:
      changed in interface it.unimi.dsi.fastutil.PriorityQueue<java.lang.Character>

    • size

      public int size()
      Specified by:
      size in interface it.unimi.dsi.fastutil.PriorityQueue<java.lang.Character>

    • clear

      public void clear()
      Specified by:
      clear in interface it.unimi.dsi.fastutil.PriorityQueue<java.lang.Character>

    • trim

      public void trim()
      Trims the underlying array so that it has exactly size() elements.

    • comparator

      public CharComparator comparator()
      Description copied from interface: CharPriorityQueue
      Returns the comparator associated with this priority queue, or null if it uses its elements' natural ordering.
      Specified by:
      comparator in interface CharPriorityQueue
      Specified by:
      comparator in interface it.unimi.dsi.fastutil.PriorityQueue<java.lang.Character>
      Returns:
      the comparator associated with this priority queue.
      See Also:
      PriorityQueue.comparator()