java.util
Class PriorityQueue<E>

java.lang.Object
  extended by java.util.AbstractCollection<E>
      extended by java.util.AbstractQueue<E>
          extended by java.util.PriorityQueue<E>
All Implemented Interfaces:
Serializable, Iterable<E>, Collection<E>, java.util.Queue<E>

public class PriorityQueue<E>
extends java.util.AbstractQueue<E>
implements Serializable

Since:
1.5
See Also:
Serialized Form

Constructor Summary
PriorityQueue()
           
PriorityQueue(Collection<? extends E> c)
           
PriorityQueue(int cap)
           
PriorityQueue(int cap, Comparator<? super E> comp)
           
PriorityQueue(PriorityQueue<? extends E> c)
           
PriorityQueue(SortedSet<? extends E> c)
           
 
Method Summary
 boolean addAll(Collection<? extends E> c)
          Add all the elements of a given collection to this collection (optional operation).
 void clear()
          Remove all elements from the collection (optional operation).
 Comparator<? super E> comparator()
           
 Iterator<E> iterator()
          Return an Iterator over this collection.
 boolean offer(E o)
           
 E peek()
           
 E poll()
           
 boolean remove(Object o)
          Remove a single instance of an object from this collection (optional operation).
 int size()
          Return the number of elements in this collection.
 
Methods inherited from class java.util.AbstractQueue
add, element, remove
 
Methods inherited from class java.util.AbstractCollection
contains, containsAll, isEmpty, removeAll, retainAll, toArray, toArray, toString
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface java.util.Collection
contains, containsAll, equals, hashCode, isEmpty, removeAll, retainAll, toArray, toArray
 

Constructor Detail

PriorityQueue

public PriorityQueue()

PriorityQueue

public PriorityQueue(Collection<? extends E> c)

PriorityQueue

public PriorityQueue(int cap)

PriorityQueue

public PriorityQueue(int cap,
                     Comparator<? super E> comp)

PriorityQueue

public PriorityQueue(PriorityQueue<? extends E> c)

PriorityQueue

public PriorityQueue(SortedSet<? extends E> c)
Method Detail

clear

public void clear()
Description copied from class: AbstractCollection
Remove all elements from the collection (optional operation). This implementation obtains an iterator over the collection and calls next and remove on it repeatedly (thus this method will fail with an UnsupportedOperationException if the Iterator's remove method does) until there are no more elements to remove. Many implementations will have a faster way of doing this.

Specified by:
clear in interface Collection<E>
Overrides:
clear in class java.util.AbstractQueue<E>
See Also:
Iterator.remove()

comparator

public Comparator<? super E> comparator()

iterator

public Iterator<E> iterator()
Description copied from class: AbstractCollection
Return an Iterator over this collection. The iterator must provide the hasNext and next methods and should in addition provide remove if the collection is modifiable.

Specified by:
iterator in interface Iterable<E>
Specified by:
iterator in interface Collection<E>
Specified by:
iterator in class AbstractCollection<E>
Returns:
an iterator

offer

public boolean offer(E o)
Specified by:
offer in interface java.util.Queue<E>

peek

public E peek()
Specified by:
peek in interface java.util.Queue<E>

poll

public E poll()
Specified by:
poll in interface java.util.Queue<E>

remove

public boolean remove(Object o)
Description copied from class: AbstractCollection
Remove a single instance of an object from this collection (optional operation). That is, remove one element e such that (o == null ? e == null : o.equals(e)), if such an element exists. This implementation obtains an iterator over the collection and iterates over it, testing each element for equality with the given object. If it is equal, it is removed by the iterator's remove method (thus this method will fail with an UnsupportedOperationException if the Iterator's remove method does). After the first element has been removed, true is returned; if the end of the collection is reached, false is returned.

Specified by:
remove in interface Collection<E>
Overrides:
remove in class AbstractCollection<E>
Parameters:
o - the object to remove from this collection
Returns:
true if the remove operation caused the Collection to change, or equivalently if the collection did contain o.
See Also:
Iterator.remove()

size

public int size()
Description copied from class: AbstractCollection
Return the number of elements in this collection. If there are more than Integer.MAX_VALUE elements, return Integer.MAX_VALUE.

Specified by:
size in interface Collection<E>
Specified by:
size in class AbstractCollection<E>
Returns:
the size

addAll

public boolean addAll(Collection<? extends E> c)
Description copied from class: AbstractCollection
Add all the elements of a given collection to this collection (optional operation). This implementation obtains an Iterator over the given collection and iterates over it, adding each element with the add(Object) method (thus this method will fail with an UnsupportedOperationException if the add method does). The behavior is unspecified if the specified collection is modified during the iteration, including the special case of trying addAll(this) on a non-empty collection.

Specified by:
addAll in interface Collection<E>
Overrides:
addAll in class java.util.AbstractQueue<E>
Parameters:
c - the collection to add the elements of to this collection
Returns:
true if the add operation caused the Collection to change
See Also:
AbstractCollection.add(Object)