public class CharArrayPriorityQueue extends java.lang.Object implements CharPriorityQueue, java.io.Serializable
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.
This implementation is extremely inefficient, but it is difficult to beat when the size of the queue is very small.
| Constructor and Description |
|---|
CharArrayPriorityQueue()
Creates a new empty queue using the natural order.
|
CharArrayPriorityQueue(char[] a)
Wraps a given array in a queue using the natural order.
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CharArrayPriorityQueue(char[] a,
CharComparator c)
Wraps a given array in a queue using a given comparator.
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CharArrayPriorityQueue(char[] a,
int size)
Wraps a given array in a queue using the natural order.
|
CharArrayPriorityQueue(char[] a,
int size,
CharComparator c)
Wraps a given array in a queue using a given comparator.
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CharArrayPriorityQueue(CharComparator c)
Creates a new empty queue with a given comparator.
|
CharArrayPriorityQueue(int capacity)
Creates a new empty queue with a given capacity and using the natural order.
|
CharArrayPriorityQueue(int capacity,
CharComparator c)
Creates a new empty queue with a given capacity and comparator.
|
| Modifier and Type | Method and Description |
|---|---|
void |
changed()
Notifies the queue that the first element has changed (optional operation).
|
void |
clear()
Removes all elements from this queue.
|
CharComparator |
comparator()
Returns the comparator associated with this priority queue, or null if it
uses its elements' natural ordering.
|
char |
dequeueChar()
Dequeues the first element from the queue.
|
void |
enqueue(char x)
Enqueues a new element.
|
char |
firstChar()
Returns the first element of the queue.
|
int |
size()
Returns the number of elements in this queue.
|
void |
trim()
Trims the underlying array so that it has exactly
size() elements. |
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, waitdequeue, enqueue, first, last, lastCharisEmptypublic CharArrayPriorityQueue(int capacity,
CharComparator c)
capacity - the initial capacity of this queue.c - the comparator used in this queue, or null for the natural
order.public CharArrayPriorityQueue(int capacity)
capacity - the initial capacity of this queue.public CharArrayPriorityQueue(CharComparator c)
c - the comparator used in this queue, or null for the natural
order.public CharArrayPriorityQueue()
public CharArrayPriorityQueue(char[] a,
int size,
CharComparator c)
The queue returned by this method will be backed by the given array.
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.public CharArrayPriorityQueue(char[] a,
CharComparator c)
The queue returned by this method will be backed by the given array.
a - an array.c - the comparator used in this queue, or null for the natural
order.public CharArrayPriorityQueue(char[] a,
int size)
The queue returned by this method will be backed by the given array.
a - an array.size - the number of elements to be included in the queue.public CharArrayPriorityQueue(char[] a)
The queue returned by this method will be backed by the given array.
a - an array.public void enqueue(char x)
CharPriorityQueueenqueue in interface CharPriorityQueuex - the element to enqueue.PriorityQueue.enqueue(Object)public char dequeueChar()
CharPriorityQueuedequeueChar in interface CharPriorityQueueCharPriorityQueue.dequeue()public char firstChar()
CharPriorityQueuefirstChar in interface CharPriorityQueueCharPriorityQueue.first()public void changed()
PriorityQueueThis default implementation just throws an UnsupportedOperationException.
changed in interface PriorityQueue<java.lang.Character>public int size()
PriorityQueuesize in interface PriorityQueue<java.lang.Character>public void clear()
PriorityQueueclear in interface PriorityQueue<java.lang.Character>public void trim()
size() elements.public CharComparator comparator()
CharPriorityQueue
Note that this specification strengthens the one given in
PriorityQueue.comparator().
comparator in interface CharPriorityQueuecomparator in interface PriorityQueue<java.lang.Character>PriorityQueue.comparator()