K - the type of keys maintained by this heapV - the type of values maintained by this heappublic class BinaryArrayAddressableHeap<K,V> extends Object implements Serializable
Comparator provided at heap creation time, depending on which
constructor is used.
The implementation uses an array in order to store the elements and
automatically maintains the size of the array much like a
Vector does, providing amortized O(log(n)) time cost for
the insert and deleteMin operations. Operation
findMin, is a worst-case O(1) operation. Operations delete
and decreaseKey take worst-case O(log(n)) time. The bounds are
worst-case if the user initializes the heap with a capacity larger or equal
to the total number of elements that are going to be inserted into the heap.
Constructing such a heap from an array of elements can be performed using the
method heapify(Object[], Object[]) or
heapify(Object[], Object[], Comparator) in linear time.
Note that the ordering maintained by a binary heap, like any heap, and
whether or not an explicit comparator is provided, must be consistent
with equals if this heap is to correctly implement the
Heap interface. (See Comparable or Comparator for a
precise definition of consistent with equals.) This is so because
the Heap interface is defined in terms of the equals
operation, but a binary heap performs all key comparisons using its
compareTo (or compare) method, so two keys that are deemed
equal by this method are, from the standpoint of the binary heap, equal. The
behavior of a heap is well-defined even if its ordering is
inconsistent with equals; it just fails to obey the general contract
of the Heap interface.
Note that this implementation is not synchronized. If multiple threads access a heap concurrently, and at least one of the threads modifies the heap structurally, it must be synchronized externally. (A structural modification is any operation that adds or deletes one or more elements or changing the key of some element.) This is typically accomplished by synchronizing on some object that naturally encapsulates the heap.
AddressableHeap.Handle<K,V>| Modifier and Type | Field and Description |
|---|---|
static int |
DEFAULT_HEAP_CAPACITY
Default initial capacity of the binary heap.
|
| Constructor and Description |
|---|
BinaryArrayAddressableHeap()
Constructs a new, empty heap, using the natural ordering of its keys.
|
BinaryArrayAddressableHeap(Comparator<? super K> comparator)
Constructs a new, empty heap, ordered according to the given comparator.
|
BinaryArrayAddressableHeap(Comparator<? super K> comparator,
int capacity)
Constructs a new, empty heap, with a provided initial capacity ordered
according to the given comparator.
|
BinaryArrayAddressableHeap(int capacity)
Constructs a new, empty heap, with a provided initial capacity using the
natural ordering of its keys.
|
| Modifier and Type | Method and Description |
|---|---|
void |
clear()
Clear all the elements of the heap.
|
Comparator<? super K> |
comparator()
Returns the comparator used to order the keys in this AddressableHeap, or
null if this heap uses the natural
ordering of its keys. |
AddressableHeap.Handle<K,V> |
deleteMin()
Delete and return an element with the minimum key.
|
AddressableHeap.Handle<K,V> |
findMin()
Find an element with the minimum key.
|
static <K,V> BinaryArrayAddressableHeap<K,V> |
heapify(K[] keys,
V[] values)
Create a heap from an array of elements.
|
static <K,V> BinaryArrayAddressableHeap<K,V> |
heapify(K[] keys,
V[] values,
Comparator<? super K> comparator)
Create a heap from an array of elements.
|
AddressableHeap.Handle<K,V> |
insert(K key)
Insert a new element into the heap with a null value.
|
AddressableHeap.Handle<K,V> |
insert(K key,
V value)
Insert a new element into the heap.
|
boolean |
isEmpty()
Returns
true if this heap is empty. |
long |
size()
Returns the number of elements in the heap.
|
public static final int DEFAULT_HEAP_CAPACITY
public BinaryArrayAddressableHeap()
All keys inserted into the heap must implement the Comparable
interface. Furthermore, all such keys must be mutually
comparable: k1.compareTo(k2) must not throw a
ClassCastException for any keys k1 and k2 in the
heap. If the user attempts to put a key into the heap that violates this
constraint (for example, the user attempts to put a string key into a
heap whose keys are integers), the insert(Object key) call will
throw a ClassCastException.
The initial capacity of the heap is DEFAULT_HEAP_CAPACITY and
adjusts automatically based on the sequence of insertions and deletions.
public BinaryArrayAddressableHeap(int capacity)
All keys inserted into the heap must implement the Comparable
interface. Furthermore, all such keys must be mutually
comparable: k1.compareTo(k2) must not throw a
ClassCastException for any keys k1 and k2 in the
heap. If the user attempts to put a key into the heap that violates this
constraint (for example, the user attempts to put a string key into a
heap whose keys are integers), the insert(Object key) call will
throw a ClassCastException.
The initial capacity of the heap is provided by the user and is adjusted automatically based on the sequence of insertions and deletions. The capacity will never become smaller than the initial requested capacity.
capacity - the initial heap capacitypublic BinaryArrayAddressableHeap(Comparator<? super K> comparator)
All keys inserted into the heap must be mutually comparable by
the given comparator: comparator.compare(k1,
k2) must not throw a ClassCastException for any keys k1
and k2 in the heap. If the user attempts to put a key into the
heap that violates this constraint, the insert(Object key) call
will throw a ClassCastException.
The initial capacity of the heap is DEFAULT_HEAP_CAPACITY and
adjusts automatically based on the sequence of insertions and deletions.
comparator - the comparator that will be used to order this heap. If
null, the natural ordering of
the keys will be used.public BinaryArrayAddressableHeap(Comparator<? super K> comparator, int capacity)
All keys inserted into the heap must be mutually comparable by
the given comparator: comparator.compare(k1,
k2) must not throw a ClassCastException for any keys k1
and k2 in the heap. If the user attempts to put a key into the
heap that violates this constraint, the insert(Object key) call
will throw a ClassCastException.
The initial capacity of the heap is provided by the user and is adjusted automatically based on the sequence of insertions and deletions. The capacity will never become smaller than the initial requested capacity.
comparator - the comparator that will be used to order this heap. If
null, the natural ordering of
the keys will be used.capacity - the initial heap capacitypublic static <K,V> BinaryArrayAddressableHeap<K,V> heapify(K[] keys, V[] values)
K - the type of keys maintained by the heapV - the type of values maintained by the heapkeys - an array of keysvalues - an array of valuesIllegalArgumentException - in case the array is nullpublic static <K,V> BinaryArrayAddressableHeap<K,V> heapify(K[] keys, V[] values, Comparator<? super K> comparator)
K - the type of keys maintained by the heapV - the type of values maintained by the heapkeys - an array of keysvalues - an array of valuescomparator - the comparator to useIllegalArgumentException - in case the array is nullpublic AddressableHeap.Handle<K,V> findMin()
findMin in interface AddressableHeap<K,V>public boolean isEmpty()
true if this heap is empty.isEmpty in interface AddressableHeap<K,V>true if this heap is empty, false otherwisepublic long size()
size in interface AddressableHeap<K,V>public Comparator<? super K> comparator()
null if this heap uses the natural
ordering of its keys.comparator in interface AddressableHeap<K,V>null if this addressable heap uses the natural ordering
of its keyspublic void clear()
AddressableHeap.Handle.decreaseKey(Object) and AddressableHeap.Handle.delete() is
undefined.clear in interface AddressableHeap<K,V>public AddressableHeap.Handle<K,V> insert(K key)
insert in interface AddressableHeap<K,V>key - the element's keypublic AddressableHeap.Handle<K,V> insert(K key, V value)
insert in interface AddressableHeap<K,V>key - the element's keyvalue - the element's valuepublic AddressableHeap.Handle<K,V> deleteMin()
AddressableHeap.Handle.getKey()
and AddressableHeap.Handle.getValue() can be used.deleteMin in interface AddressableHeap<K,V>Copyright © 2018. All rights reserved.