Package org.apache.commons.collections

Class BinaryHeap

java.lang.Object

java.util.AbstractCollection

org.apache.commons.collections.BinaryHeap

All Implemented Interfaces:

Iterable, Collection, Buffer, PriorityQueue

@Deprecated(since="2021-04-30")
public final class BinaryHeap
extends AbstractCollection
implements PriorityQueue, Buffer

Deprecated.

Replaced by PriorityBuffer in buffer subpackage. Due to be removed in v4.0.

Binary heap implementation of PriorityQueue.

The PriorityQueue interface has now been replaced for most uses by the Buffer interface. This class and the interface are retained for backwards compatibility. The intended replacement is PriorityBuffer.

The removal order of a binary heap is based on either the natural sort order of its elements or a specified Comparator. The pop() method always returns the first element as determined by the sort order. (The isMinHeap flag in the constructors can be used to reverse the sort order, in which case pop() will always remove the last element.) The removal order is not the same as the order of iteration; elements are returned by the iterator in no particular order.

The insert(Object) and pop() operations perform in logarithmic time. The peek() operation performs in constant time. All other operations perform in linear time or worse.

Note that this implementation is not synchronized. Use SynchronizedPriorityQueue to provide synchronized access to a BinaryHeap:

  PriorityQueue heap = new SynchronizedPriorityQueue(new BinaryHeap());
  

Since:

Commons Collections 1.0

Constructor Summary

Constructors

Constructor	Description
BinaryHeap()	Deprecated. Constructs a new minimum binary heap.
BinaryHeap(boolean isMinHeap)	Deprecated. Constructs a new minimum or maximum binary heap
BinaryHeap(boolean isMinHeap, Comparator comparator)	Deprecated. Constructs a new BinaryHeap.
BinaryHeap(int capacity)	Deprecated. Constructs a new minimum binary heap with the specified initial capacity.
BinaryHeap(int capacity, boolean isMinHeap)	Deprecated. Constructs a new minimum or maximum binary heap with the specified initial capacity.
BinaryHeap(int capacity, boolean isMinHeap, Comparator comparator)	Deprecated. Constructs a new BinaryHeap.
BinaryHeap(int capacity, Comparator comparator)	Deprecated. Constructs a new BinaryHeap.
BinaryHeap(Comparator comparator)	Deprecated. Constructs a new BinaryHeap that will use the given comparator to order its elements.

Method Summary

Modifier and Type	Method	Description
boolean	add(Object object)	Deprecated. Adds an object to this heap.
void	clear()	Deprecated. Clears all elements from queue.
Object	get()	Deprecated. Returns the priority element.
void	insert(Object element)	Deprecated. Inserts an element into queue.
boolean	isEmpty()	Deprecated. Tests if queue is empty.
boolean	isFull()	Deprecated. Tests if queue is full.
Iterator	iterator()	Deprecated. Returns an iterator over this heap's elements.
Object	peek()	Deprecated. Returns the element on top of heap but don't remove it.
Object	pop()	Deprecated. Returns the element on top of heap and remove it.
Object	remove()	Deprecated. Removes the priority element.
int	size()	Deprecated. Returns the number of elements in this heap.
String	toString()	Deprecated. Returns a string representation of this heap.

Methods inherited from class java.util.AbstractCollection

addAll, contains, containsAll, remove, removeAll, retainAll, toArray, toArray

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Collection

addAll, contains, containsAll, equals, hashCode, parallelStream, remove, removeAll, removeIf, retainAll, spliterator, stream, toArray, toArray, toArray

Methods inherited from interface java.lang.Iterable

forEach

Constructor Details

BinaryHeap

public BinaryHeap()

Deprecated.

Constructs a new minimum binary heap.

BinaryHeap

public BinaryHeap(Comparator comparator)

Deprecated.

Constructs a new BinaryHeap that will use the given comparator to order its elements.

Parameters:

comparator - the comparator used to order the elements, null means use natural order

BinaryHeap

public BinaryHeap(int capacity)

Deprecated.

Constructs a new minimum binary heap with the specified initial capacity.

Parameters:

capacity - The initial capacity for the heap. This value must be greater than zero.

Throws:

IllegalArgumentException - if capacity is <= 0

BinaryHeap

public BinaryHeap(int capacity,
 Comparator comparator)

Deprecated.

Constructs a new BinaryHeap.

Parameters:

capacity - the initial capacity for the heap

comparator - the comparator used to order the elements, null means use natural order

Throws:

IllegalArgumentException - if capacity is <= 0

BinaryHeap

public BinaryHeap(boolean isMinHeap)

Deprecated.

Constructs a new minimum or maximum binary heap

Parameters:

isMinHeap - if true the heap is created as a minimum heap; otherwise, the heap is created as a maximum heap

BinaryHeap

public BinaryHeap(boolean isMinHeap,
 Comparator comparator)

Deprecated.

Constructs a new BinaryHeap.

Parameters:

isMinHeap - true to use the order imposed by the given comparator; false to reverse that order

comparator - the comparator used to order the elements, null means use natural order

BinaryHeap

public BinaryHeap(int capacity,
 boolean isMinHeap)

Deprecated.

Constructs a new minimum or maximum binary heap with the specified initial capacity.

Parameters:

capacity - the initial capacity for the heap. This value must be greater than zero.

isMinHeap - if true the heap is created as a minimum heap; otherwise, the heap is created as a maximum heap.

Throws:

IllegalArgumentException - if capacity is <= 0

BinaryHeap

public BinaryHeap(int capacity,
 boolean isMinHeap,
 Comparator comparator)

Deprecated.

Constructs a new BinaryHeap.

Parameters:

capacity - the initial capacity for the heap

isMinHeap - true to use the order imposed by the given comparator; false to reverse that order

comparator - the comparator used to order the elements, null means use natural order

Throws:

IllegalArgumentException - if capacity is <= 0

Method Details

clear

public void clear()

Deprecated.

Clears all elements from queue.

Specified by:

clear in interface Collection

Specified by:

clear in interface PriorityQueue

Overrides:

clear in class AbstractCollection

isEmpty

public boolean isEmpty()

Deprecated.

Tests if queue is empty.

Specified by:

isEmpty in interface Collection

Specified by:

isEmpty in interface PriorityQueue

Overrides:

isEmpty in class AbstractCollection

Returns:

true if queue is empty; false otherwise.

isFull

public boolean isFull()

Deprecated.

Tests if queue is full.

Returns:

true if queue is full; false otherwise.

insert

public void insert(Object element)

Deprecated.

Inserts an element into queue.

Specified by:

insert in interface PriorityQueue

Parameters:

element - the element to be inserted

peek

public Object peek()
            throws NoSuchElementException

Deprecated.

Returns the element on top of heap but don't remove it.

Specified by:

peek in interface PriorityQueue

Returns:

the element at top of heap

Throws:

NoSuchElementException - if isEmpty() == true

pop

public Object pop()
           throws NoSuchElementException

Deprecated.

Returns the element on top of heap and remove it.

Specified by:

pop in interface PriorityQueue

Returns:

the element at top of heap

Throws:

NoSuchElementException - if isEmpty() == true

toString

public String toString()

Deprecated.

Returns a string representation of this heap. The returned string is similar to those produced by standard JDK collections.

Overrides:

toString in class AbstractCollection

Returns:

a string representation of this heap

iterator

public Iterator iterator()

Deprecated.

Returns an iterator over this heap's elements.

Specified by:

iterator in interface Collection

Specified by:

iterator in interface Iterable

Specified by:

iterator in class AbstractCollection

Returns:

an iterator over this heap's elements

add

public boolean add(Object object)

Deprecated.

Adds an object to this heap. Same as insert(Object).

Specified by:

add in interface Collection

Overrides:

add in class AbstractCollection

Parameters:

object - the object to add

Returns:

true, always

get

public Object get()

Deprecated.

Returns the priority element. Same as peek().

Specified by:

get in interface Buffer

Returns:

the priority element

Throws:

BufferUnderflowException - if this heap is empty

remove

public Object remove()

Deprecated.

Removes the priority element. Same as pop().

Specified by:

remove in interface Buffer

Returns:

the removed priority element

Throws:

BufferUnderflowException - if this heap is empty

size

public int size()

Deprecated.

Returns the number of elements in this heap.

Specified by:

size in interface Collection

Specified by:

size in class AbstractCollection

Returns:

the number of elements in this heap