ObjectArrayIndirectPriorityQueue (fastutil 8.1.1)

java.lang.Object
- it.unimi.dsi.fastutil.objects.ObjectArrayIndirectPriorityQueue<K>

All Implemented Interfaces:

IndirectPriorityQueue<K>
```
public class ObjectArrayIndirectPriorityQueue<K>
extends java.lang.Object
implements IndirectPriorityQueue<K>
```
A type-specific array-based semi-indirect priority queue.
Instances of this class use as reference list a reference array, which must be provided to each constructor, and represent a priority queue using a backing array of integer indices—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.
This implementation is extremely inefficient, but it is difficult to beat when the size of the queue is very small. Moreover, it allows to enqueue several time the same index, without limitations.

Constructor Summary

Constructors
Constructor and Description
`ObjectArrayIndirectPriorityQueue(K[] refArray)` Creates a new empty queue with capacity equal to the length of the reference array and using the natural order.
`ObjectArrayIndirectPriorityQueue(K[] refArray, java.util.Comparator<? super K> c)` Creates a new empty queue with capacity equal to the length of the reference array and a given comparator.
`ObjectArrayIndirectPriorityQueue(K[] refArray, int capacity)` Creates a new empty queue with given capacity and using the natural order.
`ObjectArrayIndirectPriorityQueue(K[] refArray, int[] a)` Wraps a given array in a queue using the natural order.
`ObjectArrayIndirectPriorityQueue(K[] refArray, int[] a, java.util.Comparator<? super K> c)` Wraps a given array in a queue using a given comparator.
`ObjectArrayIndirectPriorityQueue(K[] refArray, int[] a, int size)` Wraps a given array in a queue using the natural order.
`ObjectArrayIndirectPriorityQueue(K[] refArray, int[] a, int size, java.util.Comparator<? super K> c)` Wraps a given array in a queue using a given comparator.
`ObjectArrayIndirectPriorityQueue(K[] refArray, int capacity, java.util.Comparator<? super K> c)` Creates a new empty queue without elements with a given capacity and comparator.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`allChanged()` Signals the queue that all elements have changed.
`void`	`changed()` Notifies this queue that the first element has changed (optional operation).
`void`	`changed(int index)` Notifies this queue that the specified element has changed (optional operation).
`void`	`clear()` Removes all elements from this queue.
`java.util.Comparator<? super K>`	`comparator()` Returns the comparator associated with this queue, or `null` if it uses its elements' natural ordering.
`int`	`dequeue()` Dequeues the first element from this queue.
`void`	`enqueue(int x)` Enqueues a new element.
`int`	`first()` Returns the first element of this queue.
`int`	`front(int[] a)` Writes in the provided array the front of the queue, that is, the set of indices whose elements have the same priority as the top.
`int`	`last()` Returns the last element of this queue, that is, the element the would be dequeued last (optional operation).
`boolean`	`remove(int index)` Removes the specified element from this queue (optional operation).
`int`	`size()` Returns the number of elements in this queue.
`java.lang.String`	`toString()`
`void`	`trim()` Trims the backing array so that it has exactly `size()` elements.

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface it.unimi.dsi.fastutil.IndirectPriorityQueue
contains, isEmpty

- Constructor Detail
  - ObjectArrayIndirectPriorityQueue
```
public ObjectArrayIndirectPriorityQueue(K[] refArray,
                                        int capacity,
                                        java.util.Comparator<? super K> c)
```
    Creates a new empty queue without elements with a given capacity and comparator.
    
    Parameters:
    
    refArray - the reference array.
    
    capacity - the initial capacity of this queue.
    
    c - the comparator used in this queue, or null for the natural order.
  - ObjectArrayIndirectPriorityQueue
```
public ObjectArrayIndirectPriorityQueue(K[] refArray,
                                        int capacity)
```
    Creates a new empty queue with given capacity and using the natural order.
    
    Parameters:
    
    refArray - the reference array.
    
    capacity - the initial capacity of this queue.
  - ObjectArrayIndirectPriorityQueue
```
public ObjectArrayIndirectPriorityQueue(K[] refArray,
                                        java.util.Comparator<? super K> c)
```
    Creates a new empty queue with capacity equal to the length of the reference array and a given comparator.
    
    Parameters:
    
    refArray - the reference array.
    
    c - the comparator used in this queue, or null for the natural order.
  - ObjectArrayIndirectPriorityQueue
```
public ObjectArrayIndirectPriorityQueue(K[] refArray)
```
    Creates a new empty queue with capacity equal to the length of the reference array and using the natural order.
    
    Parameters:
    
    refArray - the reference array.
  - ObjectArrayIndirectPriorityQueue
```
public ObjectArrayIndirectPriorityQueue(K[] refArray,
                                        int[] a,
                                        int size,
                                        java.util.Comparator<? super K> 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:
    
    refArray - the reference array.
    
    a - an array of indices into refArray.
    
    size - the number of elements to be included in the queue.
    
    c - the comparator used in this queue, or null for the natural order.
  - ObjectArrayIndirectPriorityQueue
```
public ObjectArrayIndirectPriorityQueue(K[] refArray,
                                        int[] a,
                                        java.util.Comparator<? super K> 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:
    
    refArray - the reference array.
    
    a - an array of indices into refArray.
    
    c - the comparator used in this queue, or null for the natural order.
  - ObjectArrayIndirectPriorityQueue
```
public ObjectArrayIndirectPriorityQueue(K[] refArray,
                                        int[] 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:
    
    refArray - the reference array.
    
    a - an array of indices into refArray.
    
    size - the number of elements to be included in the queue.
  - ObjectArrayIndirectPriorityQueue
```
public ObjectArrayIndirectPriorityQueue(K[] refArray,
                                        int[] 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:
    
    refArray - the reference array.
    
    a - an array of indices into refArray.
- Method Detail
  - enqueue
```
public void enqueue(int x)
```
    Enqueues a new element.
    Note that for efficiency reasons this method will not throw an exception when x is already in the queue. However, the queue state will become inconsistent and the following behaviour will not be predictable.
    
    Specified by:
    
    enqueue in interface IndirectPriorityQueue<K>
    
    Parameters:
    
    x - the element to enqueue.
  - dequeue
```
public int dequeue()
```
    Description copied from interface: IndirectPriorityQueue
    
    Dequeues the first element from this queue.
    
    Specified by:
    
    dequeue in interface IndirectPriorityQueue<K>
    
    Returns:
    
    the dequeued element.
  - first
```
public int first()
```
    Description copied from interface: IndirectPriorityQueue
    
    Returns the first element of this queue.
    
    Specified by:
    
    first in interface IndirectPriorityQueue<K>
    
    Returns:
    
    the first element.
  - last
```
public int last()
```
    Description copied from interface: IndirectPriorityQueue
    
    Returns the last element of this queue, that is, the element the would be dequeued last (optional operation).
    This default implementation just throws an UnsupportedOperationException.
    
    Specified by:
    
    last in interface IndirectPriorityQueue<K>
    
    Returns:
    
    the last element.
  - changed
```
public void changed()
```
    Description copied from interface: IndirectPriorityQueue
    
    Notifies this queue that the first element has changed (optional operation).
    This default implementation just calls IndirectPriorityQueue.changed(int) with argument IndirectPriorityQueue.first().
    
    Specified by:
    
    changed in interface IndirectPriorityQueue<K>
  - changed
```
public void changed(int index)
```
    Notifies this queue that the specified element has changed (optional operation).
    Note that the specified element must belong to this queue.
    This default implementation just throws an UnsupportedOperationException.
    Note that for efficiency reasons this method will not throw an exception when index is not in the queue.
    
    Specified by:
    
    changed in interface IndirectPriorityQueue<K>
    
    Parameters:
    
    index - the element that has changed.
  - allChanged
```
public void allChanged()
```
    Signals the queue that all elements have changed.
    
    Specified by:
    
    allChanged in interface IndirectPriorityQueue<K>
  - remove
```
public boolean remove(int index)
```
    Description copied from interface: IndirectPriorityQueue
    
    Removes the specified element from this queue (optional operation).
    This default implementation just throws an UnsupportedOperationException.
    
    Specified by:
    
    remove in interface IndirectPriorityQueue<K>
    
    Parameters:
    
    index - the element to be removed.
    
    Returns:
    
    true if the index was in the queue.
  - front
```
public int front(int[] a)
```
    Writes in the provided array the front of the queue, that is, the set of indices whose elements have the same priority as the top.
    
    Specified by:
    
    front in interface IndirectPriorityQueue<K>
    
    Parameters:
    
    a - an array whose initial part will be filled with the frnot (must be sized as least as the heap size).
    
    Returns:
    
    the number of elements of the front.
  - size
```
public int size()
```
    Description copied from interface: IndirectPriorityQueue
    
    Returns the number of elements in this queue.
    
    Specified by:
    
    size in interface IndirectPriorityQueue<K>
    
    Returns:
    
    the number of elements in this queue.
  - clear
```
public void clear()
```
    Description copied from interface: IndirectPriorityQueue
    
    Removes all elements from this queue.
    
    Specified by:
    
    clear in interface IndirectPriorityQueue<K>
  - trim
```
public void trim()
```
    Trims the backing array so that it has exactly size() elements.
  - comparator
```
public java.util.Comparator<? super K> comparator()
```
    Description copied from interface: IndirectPriorityQueue
    
    Returns the comparator associated with this queue, or null if it uses its elements' natural ordering.
    
    Specified by:
    
    comparator in interface IndirectPriorityQueue<K>
    
    Returns:
    
    the comparator associated with this sorted set, or null if it uses its elements' natural ordering.
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object

Class ObjectArrayIndirectPriorityQueue<K>

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

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

Constructor Detail

ObjectArrayIndirectPriorityQueue

ObjectArrayIndirectPriorityQueue

ObjectArrayIndirectPriorityQueue

ObjectArrayIndirectPriorityQueue

ObjectArrayIndirectPriorityQueue

ObjectArrayIndirectPriorityQueue

ObjectArrayIndirectPriorityQueue

ObjectArrayIndirectPriorityQueue

Method Detail

enqueue

dequeue

first

last

changed

changed

allChanged

remove

front

size

clear

trim

comparator

toString