org.mini2Dx.core.collections.concurrent

Class ConcurrentQueue<T>

java.lang.Object

org.mini2Dx.gdx.utils.Queue<T>

org.mini2Dx.core.collections.concurrent.ConcurrentQueue<T>

All Implemented Interfaces:

java.lang.Iterable<T>, ConcurrentCollection

public class ConcurrentQueue<T>
extends org.mini2Dx.gdx.utils.Queue<T>
implements ConcurrentCollection

Nested Class Summary

Nested classes/interfaces inherited from class org.mini2Dx.gdx.utils.Queue

org.mini2Dx.gdx.utils.Queue.QueueIterable<T>, org.mini2Dx.gdx.utils.Queue.QueueIterator<T>

Field Summary

Fields

Modifier and Type	Field and Description
protected ReadWriteLock	lock

Fields inherited from class org.mini2Dx.gdx.utils.Queue

head, size, tail, values

Constructor Summary

Constructors

Constructor and Description
ConcurrentQueue() Creates a new Queue which can hold 16 values without needing to resize backing array.
ConcurrentQueue(int initialSize) Creates a new Queue which can hold the specified number of values without needing to resize backing array.
ConcurrentQueue(int initialSize, java.lang.Class<T> type) Creates a new Queue which can hold the specified number of values without needing to resize backing array.

Method Summary

Modifier and Type	Method and Description
void	addFirst(T object) Prepend given object to the head.
void	addLast(T object) Append given object to the tail.
void	clear() Removes all values from this queue.
void	ensureCapacity(int additional) Increases the size of the backing array to accommodate the specified number of additional items.
boolean	equals(java.lang.Object obj)
boolean	equalsIdentity(java.lang.Object o) Uses == for comparison of each item.
T	first() Returns the first (head) item in the queue (without removing it).
T	get(int index) Retrieves the value in queue without removing it.
ReadWriteLock	getLock() Returns the collection's ReadWriteLock
int	hashCode()
int	indexOf(T value, boolean identity) Returns the index of first occurrence of value in the queue, or -1 if no such value exists.
boolean	isEmpty() Returns true if the queue is empty.
java.util.Iterator<T>	iterator() Returns an iterator for the items in the queue.
T	last() Returns the last (tail) item in the queue (without removing it).
boolean	notEmpty() Returns true if the queue has one or more items.
T	removeFirst() Remove the first item from the queue.
T	removeIndex(int index) Removes and returns the item at the specified index.
T	removeLast() Remove the last item from the queue.
boolean	removeValue(T value, boolean identity) Removes the first instance of the specified value in the queue.
java.lang.String	toString()

Methods inherited from class org.mini2Dx.gdx.utils.Queue

resize

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

lock

protected ReadWriteLock lock

Constructor Detail

ConcurrentQueue

public ConcurrentQueue()

Creates a new Queue which can hold 16 values without needing to resize backing array.

ConcurrentQueue

public ConcurrentQueue(int initialSize)

Creates a new Queue which can hold the specified number of values without needing to resize backing array.

Parameters:

initialSize -

ConcurrentQueue

public ConcurrentQueue(int initialSize,
                       java.lang.Class<T> type)

Creates a new Queue which can hold the specified number of values without needing to resize backing array. This creates backing array of the specified type via reflection, which is necessary only when accessing the backing array directly.

Parameters:

initialSize -

type -

Method Detail

addLast

public void addLast(T object)

Append given object to the tail. (enqueue to tail) Unless backing array needs resizing, operates in O(1) time.

Overrides:

addLast in class org.mini2Dx.gdx.utils.Queue<T>

Parameters:

object - can be null

addFirst

public void addFirst(T object)

Prepend given object to the head. (enqueue to head) Unless backing array needs resizing, operates in O(1) time.

Overrides:

addFirst in class org.mini2Dx.gdx.utils.Queue<T>

Parameters:

object - can be null

See Also:

addLast(Object)

ensureCapacity

public void ensureCapacity(int additional)

Increases the size of the backing array to accommodate the specified number of additional items. Useful before adding many items to avoid multiple backing array resizes.

Overrides:

ensureCapacity in class org.mini2Dx.gdx.utils.Queue<T>

Parameters:

additional -

removeFirst

public T removeFirst()

Remove the first item from the queue. (dequeue from head) Always O(1).

Overrides:

removeFirst in class org.mini2Dx.gdx.utils.Queue<T>

Returns:

removed object

Throws:

java.util.NoSuchElementException - when queue is empty

removeLast

public T removeLast()

Remove the last item from the queue. (dequeue from tail) Always O(1).

Overrides:

removeLast in class org.mini2Dx.gdx.utils.Queue<T>

Returns:

removed object

Throws:

java.util.NoSuchElementException - when queue is empty

See Also:

removeFirst()

indexOf

public int indexOf(T value,
                   boolean identity)

Returns the index of first occurrence of value in the queue, or -1 if no such value exists.

Overrides:

indexOf in class org.mini2Dx.gdx.utils.Queue<T>

Parameters:

value -

identity - If true, == comparison will be used. If false, .equals() comparison will be used.

Returns:

An index of first occurrence of value in queue or -1 if no such value exists

removeValue

public boolean removeValue(T value,
                           boolean identity)

Removes the first instance of the specified value in the queue.

Overrides:

removeValue in class org.mini2Dx.gdx.utils.Queue<T>

Parameters:

value -

identity - If true, == comparison will be used. If false, .equals() comparison will be used.

Returns:

true if value was found and removed, false otherwise

removeIndex

public T removeIndex(int index)

Removes and returns the item at the specified index.

Overrides:

removeIndex in class org.mini2Dx.gdx.utils.Queue<T>

Parameters:

index -

notEmpty

public boolean notEmpty()

Returns true if the queue has one or more items.

Overrides:

notEmpty in class org.mini2Dx.gdx.utils.Queue<T>

isEmpty

public boolean isEmpty()

Returns true if the queue is empty.

Overrides:

isEmpty in class org.mini2Dx.gdx.utils.Queue<T>

first

public T first()

Returns the first (head) item in the queue (without removing it).

Overrides:

first in class org.mini2Dx.gdx.utils.Queue<T>

Throws:

java.util.NoSuchElementException - when queue is empty

See Also:

addFirst(Object), removeFirst()

last

public T last()

Returns the last (tail) item in the queue (without removing it).

Overrides:

last in class org.mini2Dx.gdx.utils.Queue<T>

Throws:

java.util.NoSuchElementException - when queue is empty

See Also:

addLast(Object), removeLast()

get

public T get(int index)

Retrieves the value in queue without removing it. Indexing is from the front to back, zero based. Therefore get(0) is the same as first().

Overrides:

get in class org.mini2Dx.gdx.utils.Queue<T>

Parameters:

index -

Throws:

java.lang.IndexOutOfBoundsException - when the index is negative or greater or equal than size

clear

public void clear()

Removes all values from this queue. Values in backing array are set to null to prevent memory leak, so this operates in O(n).

Overrides:

clear in class org.mini2Dx.gdx.utils.Queue<T>

iterator

public java.util.Iterator<T> iterator()

Returns an iterator for the items in the queue. Remove is supported.

Specified by:

iterator in interface java.lang.Iterable<T>

Overrides:

iterator in class org.mini2Dx.gdx.utils.Queue<T>

hashCode

public int hashCode()

Overrides:

hashCode in class org.mini2Dx.gdx.utils.Queue<T>

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class org.mini2Dx.gdx.utils.Queue<T>

toString

public java.lang.String toString()

Overrides:

toString in class org.mini2Dx.gdx.utils.Queue<T>

equalsIdentity

public boolean equalsIdentity(java.lang.Object o)

Uses == for comparison of each item.

Overrides:

equalsIdentity in class org.mini2Dx.gdx.utils.Queue<T>

Parameters:

o -

getLock

public ReadWriteLock getLock()

Description copied from interface: ConcurrentCollection

Returns the collection's ReadWriteLock

Specified by:

getLock in interface ConcurrentCollection

Returns:

the collection's ReadWriteLock