Summary: Protected Ctors | Methods | Inherited Methods | [Expand All]

public abstract class

AbstractQueue

extends AbstractCollection<E>
implements Queue<E>

java.lang.Object
↳	java.util.AbstractCollection<E>
	↳	java.util.AbstractQueue<E>

Known Direct Subclasses

ArrayBlockingQueue<E>, ConcurrentLinkedQueue<E>, DelayQueue<E extends Delayed>, LinkedBlockingQueue<E>, PriorityBlockingQueue<E>, PriorityQueue<E>, SynchronousQueue<E>

Class Overview

An abstract class which gives out skeletal implementations for some methods in Queue which include add, remove, and element that are based on offer, poll, and peek except that they throw exception to indicate the occurrence of some error instead of the return value of false or null.

Summary

Protected Constructors
	AbstractQueue() Constructor for the sub classes.

Public Methods
boolean	add(E o) Adds an element to the queue.
boolean	addAll(Collection<? extends E> c) Adds all the elements of a collection to the queue.
void	clear() Removes all elements of the queue.
E	element() Gets but not removes the element in the head of the queue.
E	remove() Gets and removes the element in the head of the queue.

[Expand]

Inherited Methods

From class java.util.AbstractCollection

boolean	add(E object) If the specified element is not contained within this collection, and addition of this element succeeds, then true will be returned.
boolean	addAll(Collection<? extends E> collection) Adds the objects in the specified Collection to this Collection.
void	clear() Removes all the elements in this collection.
boolean	contains(Object object) Searches this Collection for the specified object.
boolean	containsAll(Collection<?> collection) Searches this Collection for all objects in the specified Collection.
boolean	isEmpty() Returns true if the collection has no element, otherwise false.
abstract Iterator<E>	iterator() Returns an Iterator on the elements of this Collection.
boolean	remove(Object object) Removes the first occurrence of the specified object from this Collection.
boolean	removeAll(Collection<?> collection) Removes all occurrences in this Collection of each object in the specified Collection.
boolean	retainAll(Collection<?> collection) Removes all objects from this Collection that are not contained in the specified Collection.
abstract int	size() Returns the number of elements in this Collection.
<T> T[]	toArray(T[] contents) Returns an array containing all elements contained in this Collection.
Object[]	toArray() Returns a new array containing all elements contained in this Collection.
String	toString() Returns the string representation of this Collection.

From class java.lang.Object

Object	clone() Returns a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.
boolean	equals(Object o) Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.
void	finalize() Called by the virtual machine when there are no longer any (non-weak) references to the receiver.
final Class<? extends Object>	getClass() Returns the unique instance of java.lang.Class which represents the class of the receiver.
int	hashCode() Returns an integer hash code for the receiver.
final void	notify() Causes one thread which is `wait` ing on the receiver to be made ready to run.
final void	notifyAll() Causes all threads which are `wait` ing on the receiver to be made ready to run.
String	toString() Returns a string containing a concise, human-readable description of the receiver.
final void	wait(long time, int frac) Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by `notify` or `notifyAll`) or the expiration of the timeout.
final void	wait(long time) Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by `notify` or `notifyAll`) or the expiration of the timeout.
final void	wait() Causes the thread which sent this message to be made not ready to run pending some change in the receiver (as indicated by `notify` or `notifyAll`).

From interface java.lang.Iterable

From interface java.util.Collection

abstract boolean	add(E object) Attempts to add `object` to the contents of this `Collection`.
abstract boolean	addAll(Collection<? extends E> collection) Attempts to add all of the objects contained in `collection` to the contents of this collection.
abstract void	clear() Removes all elements from this Collection, leaving it empty.
abstract boolean	contains(Object object) Searches this Collection for the specified object.
abstract boolean	containsAll(Collection<?> collection) Searches this Collection for all objects in the specified Collection.
abstract boolean	equals(Object object) Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.
abstract int	hashCode() Returns an integer hash code for the receiver.
abstract boolean	isEmpty() Returns if this Collection has no elements, a size of zero.
abstract Iterator<E>	iterator() Returns an instance of Iterator that may be used to access the objects contained by this collection.
abstract boolean	remove(Object object) Removes the first occurrence of the specified object from this Collection.
abstract boolean	removeAll(Collection<?> collection) Removes all occurrences in this Collection of each object in the specified Collection.
abstract boolean	retainAll(Collection<?> collection) Removes all objects from this Collection that are not also found in the contents of `collection`.
abstract int	size() Returns a count of how many objects are contained by this collection.
abstract <T> T[]	toArray(T[] array) Returns an array containing all elements contained in this Collection.
abstract Object[]	toArray() Returns a new array containing all elements contained in this Collection.

From interface java.util.Queue

Protected Constructors

protected AbstractQueue ()

Constructor for the sub classes.

Public Methods

public boolean add (E o)

Adds an element to the queue.

Parameters

o	the element added to the queue.

Returns

true if the operation succeeds.

Throws

NullPointerException	if the element is null.
IllegalStateException	if the element is not allowed to be added to the queue.

public boolean addAll (Collection<? extends E> c)

Adds all the elements of a collection to the queue. If the collection is the queue itself, then an IllegalArgumentException will be thrown out. If during the process, some runtime exception is thrown out, then part of the elements in the collection that have successfully added will remain in the queue. The result of the method is undefined if the collection is modified during the process of the method.

Parameters

c	the collection to be added to the queue.

Returns

true if the operation succeeds.

Throws

NullPointerException	if the collection or any element of it is null.
IllegalArgumentException	If the collection to be added to the queue is the queue itself.

public void clear ()

Removes all elements of the queue.

public E element ()

Gets but not removes the element in the head of the queue.

Returns

the element in the head of the queue.

Throws

NoSuchElementException	if the queue is empty.

public E remove ()

Gets and removes the element in the head of the queue.

Returns

the element in the head of the queue.

Throws

NoSuchElementException	if the queue is empty.

Jan	FEB	Mar
	18
2008	2009	2010

Interfaces

Classes

Enums

Exceptions

AbstractQueue

Class Overview

Summary

Protected Constructors

protected AbstractQueue ()

Public Methods

public boolean add (E o)

Parameters

Returns

Throws

public boolean addAll (Collection<? extends E> c)

Parameters

Returns

Throws

public void clear ()

public E element ()

Returns

Throws

public E remove ()

Returns

Throws