- Type Parameters:
E
- The type of object contained in the PriorityQueueDouble.
- All Superinterfaces:
Collection<PriorityQueueNode.Double<E>>
,Iterable<PriorityQueueNode.Double<E>>
,Queue<PriorityQueueNode.Double<E>>
- All Known Subinterfaces:
MergeablePriorityQueueDouble<E,
T>
- All Known Implementing Classes:
BinaryHeapDouble
,FibonacciHeapDouble
Interface common to the classes that provide implementations of
a priority queue with double valued priorities. All PriorityQueueDouble
implementations enforce distinct elements, and use the
Object.hashCode()
and Object.equals(java.lang.Object)
methods to
to enforce distinctness, so be sure that the class of the elements
properly implements these methods, or else behavior is not guaranteed.
-
Method Summary
Modifier and TypeMethodDescriptiondefault boolean
Adds an (element, priority) pair to the PriorityQueueDouble with a specified priority, provided the element is not already in the PriorityQueueDouble.default boolean
add
(PriorityQueueNode.Double<E> pair) Adds an (element, priority) pair to the PriorityQueueDouble, provided the element is not already in the PriorityQueueDouble.default boolean
addAll
(Collection<? extends PriorityQueueNode.Double<E>> c) Adds all (element, priority) pairs from a Collection to the PriorityQueueDouble, provided the elements are not already in the PriorityQueueDouble.boolean
Changes the priority of an element if the element is present in the PriorityQueueDouble, and otherwise adds the (element, priority) pair to the PriorityQueueDouble.void
clear()
Clears the PriorityQueueDouble, removing all elements.boolean
Checks if this PriorityQueueDouble contains a given element or an (element, priority) pair with a given element.default boolean
containsAll
(Collection<?> c) Checks if this PriorityQueueDouble contains all elements or (element, priority) pairs from a given Collection.boolean
Demotes an element relative to priority order if the element is present in the PriorityQueueDouble.default PriorityQueueNode.Double<E>
element()
Gets the next (element, priority) pair in priority order from this PriorityQueueDouble, without removing it.boolean
isEmpty()
Checks if the PriorityQueueDouble is empty.iterator()
Returns an iterator over the (element, priority) pairs in a mostly arbitrary order (i.e., you must not assume any particular order).boolean
Adds an (element, priority) pair to the PriorityQueueDouble with a specified priority, provided the element is not already in the PriorityQueueDouble.boolean
offer
(PriorityQueueNode.Double<E> pair) Adds an (element, priority) pair to the PriorityQueueDouble, provided the element is not already in the PriorityQueueDouble.peek()
Gets the next (element, priority) pair in priority order from this PriorityQueueDouble, without removing it.Gets the next element in priority order from this PriorityQueueDouble, without removing it.double
Gets the priority of the next element in priority order in the PriorityQueueDouble.double
peekPriority
(E element) Gets the priority of a specified element if it is present in the PriorityQueueDouble.poll()
Removes and returns the next (element, priority) pair in priority order from this PriorityQueueDouble.Removes and returns the next element in priority order from this PriorityQueueDouble.boolean
Promotes an element relative to priority order if the element is present in the PriorityQueueDouble.default PriorityQueueNode.Double<E>
remove()
Removes and returns the next (element, priority) pair in priority order from this PriorityQueueDouble.boolean
Removes from this PriorityQueueDouble the (element, priority) pair, if present, for a specified element or element from a specified (element, priority) pair.boolean
removeAll
(Collection<?> c) Removes from this PriorityQueueDouble all (element, priority) pairs such that a given Collection c either contains the element or contains an (element, priority) pair with the same element.default E
Removes and returns the next element in priority order from this PriorityQueueDouble.boolean
retainAll
(Collection<?> c) Removes from this PriorityQueueDouble all (element, priority) pairs except for the elements or (element, priority) pairs contained in a given Collection c.int
size()
Gets the current size of the PriorityQueueDouble, which is the number of (element, value) pairs that it contains.Object[]
toArray()
Returns an array containing all of the (element, priority) pairs contained in the PriorityQueueDouble.<T> T[]
toArray
(T[] array) Returns an array containing all of the (element, priority) pairs contained in the PriorityQueueDouble.Methods inherited from interface java.util.Collection
equals, hashCode, parallelStream, removeIf, spliterator, stream, toArray
-
Method Details
-
add
Adds an (element, priority) pair to the PriorityQueueDouble with a specified priority, provided the element is not already in the PriorityQueueDouble. This method differs fromoffer(Object, double)
in that it throws an exception if the PriorityQueueDouble contains the element, while the offer method instead returns false.- Parameters:
element
- The element.priority
- The priority of the element.- Returns:
- true if the (element, priority) pair was added.
- Throws:
IllegalArgumentException
- if the priority queue already contains the element.
-
add
Adds an (element, priority) pair to the PriorityQueueDouble, provided the element is not already in the PriorityQueueDouble. This method differs fromoffer(PriorityQueueNode.Double)
in that it throws an exception if the PriorityQueueDouble contains the element, while the offer method instead returns false.- Specified by:
add
in interfaceCollection<E>
- Specified by:
add
in interfaceQueue<E>
- Parameters:
pair
- The (element, priority) pair to add.- Returns:
- true if the (element, priority) pair was added.
- Throws:
IllegalArgumentException
- if the priority queue already contains the element.
-
addAll
Adds all (element, priority) pairs from a Collection to the PriorityQueueDouble, provided the elements are not already in the PriorityQueueDouble. The default implementation calls theadd(PriorityQueueNode.Double)
for each pair in the Collection.- Specified by:
addAll
in interfaceCollection<E>
- Parameters:
c
- the Collection of (element, priority) pairs to add.- Returns:
- true if the (element, priority) pairs were added.
- Throws:
IllegalArgumentException
- if the PriorityQueueDouble already contains any of the (element, priority) pairs.
-
change
Changes the priority of an element if the element is present in the PriorityQueueDouble, and otherwise adds the (element, priority) pair to the PriorityQueueDouble.- Parameters:
element
- The element whose priority is to change.priority
- Its new priority.- Returns:
- true if and only if the PriorityQueueDouble changed as a consequence of this method call.
-
clear
void clear()Clears the PriorityQueueDouble, removing all elements.- Specified by:
clear
in interfaceCollection<E>
-
contains
Checks if this PriorityQueueDouble contains a given element or an (element, priority) pair with a given element.- Specified by:
contains
in interfaceCollection<E>
- Parameters:
o
- An element or (element, priority) pair to check for containment of the element.- Returns:
- true if and only if this PriorityQueueDouble contains the element.
-
containsAll
Checks if this PriorityQueueDouble contains all elements or (element, priority) pairs from a given Collection.- Specified by:
containsAll
in interfaceCollection<E>
- Parameters:
c
- A Collection of elements or (element, priority) pairs to check for containment.- Returns:
- true if and only if this PriorityQueueDouble contains all of the elements or (element, priority) pairs in c.
-
demote
Demotes an element relative to priority order if the element is present in the PriorityQueueDouble. For a min-heap, demotion means increasing the element's priority, while for a max-heap, demotion means decreasing its priority. If the element is not in the PriorityQueueDouble, or if its new priority is not a demotion, then this method does nothing.- Parameters:
element
- The element whose priority is to change.priority
- Its new priority.- Returns:
- true if and only if the PriorityQueueDouble changed as a consequence of this method call.
-
element
Gets the next (element, priority) pair in priority order from this PriorityQueueDouble, without removing it.
This method differs from
peek()
in that if the PriorityQueueDouble is empty, this method throws an exception, whilepeek()
returns null.This method serves a different purpose than
peekElement()
. ThepeekElement()
methods returns only the element of the (element, priority) pair, while this method returns the (element, priority) pair. This element() method is included only for full implementation of the superinterfaceQueue
.- Specified by:
element
in interfaceQueue<E>
- Returns:
- the next (element, priority) pair in priority order.
- Throws:
NoSuchElementException
- if the PriorityQueueDouble is empty
-
isEmpty
boolean isEmpty()Checks if the PriorityQueueDouble is empty.- Specified by:
isEmpty
in interfaceCollection<E>
- Returns:
- true if and only if it is empty
-
iterator
Iterator<PriorityQueueNode.Double<E>> iterator()Returns an iterator over the (element, priority) pairs in a mostly arbitrary order (i.e., you must not assume any particular order). -
offer
Adds an (element, priority) pair to the PriorityQueueDouble with a specified priority, provided the element is not already in the PriorityQueueDouble.- Parameters:
element
- The element.priority
- The priority of the element.- Returns:
- true if the (element, priority) pair was added, and false if the PriorityQueueDouble already contained the element.
-
offer
Adds an (element, priority) pair to the PriorityQueueDouble, provided the element is not already in the PriorityQueueDouble. -
peek
PriorityQueueNode.Double<E> peek()Gets the next (element, priority) pair in priority order from this PriorityQueueDouble, without removing it. -
peekPriority
double peekPriority()Gets the priority of the next element in priority order in the PriorityQueueDouble.- Returns:
- the priority of the next element in priority order.
-
peekPriority
Gets the priority of a specified element if it is present in the PriorityQueueDouble. This interface does not define the behavior when the element is not present. Implementations may define the behavior when the element is not present.- Parameters:
element
- The element whose priority is returned.- Returns:
- the priority of a specified element.
-
peekElement
E peekElement()Gets the next element in priority order from this PriorityQueueDouble, without removing it.- Returns:
- the next element in priority order, or null if empty.
-
poll
PriorityQueueNode.Double<E> poll()Removes and returns the next (element, priority) pair in priority order from this PriorityQueueDouble. -
pollElement
E pollElement()Removes and returns the next element in priority order from this PriorityQueueDouble.- Returns:
- the next element in priority order, or null if empty.
-
promote
Promotes an element relative to priority order if the element is present in the PriorityQueueDouble. For a min-heap, promotion means decreasing the element's priority, while for a max-heap, promotion means increasing its priority. If the element is not in the PriorityQueueDouble, or if its new priority is not a promotion, then this method does nothing.- Parameters:
element
- The element whose priority is to change.priority
- Its new priority.- Returns:
- true if and only if the PriorityQueueDouble changed as a consequence of this method call.
-
remove
Removes and returns the next (element, priority) pair in priority order from this PriorityQueueDouble. This method differs frompoll()
in that if the PriorityQueueDouble is empty, this method throws an exception, whilepoll()
returns null.- Specified by:
remove
in interfaceQueue<E>
- Returns:
- the next (element, priority) pair in priority order.
- Throws:
NoSuchElementException
- if the PriorityQueueDouble is empty
-
remove
Removes from this PriorityQueueDouble the (element, priority) pair, if present, for a specified element or element from a specified (element, priority) pair.- Specified by:
remove
in interfaceCollection<E>
- Parameters:
o
- An element or (element, priority) pair, such that element designates the desired pair to remove (note that if you pass an (element, priority) pair, only the element must match to cause removal.- Returns:
- true if and only if an (element, priority) pair was removed as a result of this method call.
-
removeAll
Removes from this PriorityQueueDouble all (element, priority) pairs such that a given Collection c either contains the element or contains an (element, priority) pair with the same element.- Specified by:
removeAll
in interfaceCollection<E>
- Parameters:
c
- A Collection of elements or (element, priority) pairs for removal.- Returns:
- true if and only if this PriorityQueueDouble changed as a result of this method.
-
removeElement
Removes and returns the next element in priority order from this PriorityQueueDouble. This method differs frompollElement()
in that if the PriorityQueueDouble is empty, this method throws an exception, whilepollElement()
returns null.- Returns:
- the next element in priority order.
- Throws:
NoSuchElementException
- if the PriorityQueueDouble is empty
-
retainAll
Removes from this PriorityQueueDouble all (element, priority) pairs except for the elements or (element, priority) pairs contained in a given Collection c.- Specified by:
retainAll
in interfaceCollection<E>
- Parameters:
c
- A Collection of elements or (element, priority) pairs to keep.- Returns:
- true if and only if this PriorityQueueDouble changed as a result of this method.
-
size
int size()Gets the current size of the PriorityQueueDouble, which is the number of (element, value) pairs that it contains.- Specified by:
size
in interfaceCollection<E>
- Returns:
- the current size of the PriorityQueueDouble.
-
toArray
Object[] toArray()Returns an array containing all of the (element, priority) pairs contained in the PriorityQueueDouble. The order is not guaranteed. The runtime component type is Object. The PriorityQueueDouble does not maintain any references to the array that is returned, instead creating a new array upon each call to the toArray method. The length of the array that is returned is equal to the currentsize()
of the PriorityQueueDouble.- Specified by:
toArray
in interfaceCollection<E>
- Returns:
- an array, whose runtime component type is Object, containing all of the (element, priority) pairs currently in the PriorityQueueDouble.
-
toArray
<T> T[] toArray(T[] array) Returns an array containing all of the (element, priority) pairs contained in the PriorityQueueDouble. The order is not guaranteed. The runtime component type is the same as the array passed to it as a parameter. If the specified array is large enough, then it is used, otherwise a new array is allocated whose length is equal to the currentsize()
of the PriorityQueueDouble. If the specified array is larger than the current size() of the PriorityQueueDouble, the first extra cell is set to null.- Specified by:
toArray
in interfaceCollection<E>
- Type Parameters:
T
- The component type of the array to contain the (element, priority) pairs- Parameters:
array
- The array in which to place the (element, priority) pairs, if it is sufficiently large, otherwise a new array of lengthsize()
is allocated of the same runtime type as array.- Returns:
- The array in which the (element, priority) pairs have been inserted.
- Throws:
ArrayStoreException
- if the runtime component type of array is not compatible with the type of the (element, priority) pairs.NullPointerException
- if array is null
-