Package com.tangosol.util

Class CopyOnWriteLongArray<V>

java.lang.Object

com.tangosol.util.WrapperCollections.AbstractWrapperLongArray<V>

com.tangosol.util.CopyOnWriteLongArray<V>

All Implemented Interfaces:

LongArray<V>, Serializable, Cloneable, Iterable<V>

public class CopyOnWriteLongArray<V>
extends WrapperCollections.AbstractWrapperLongArray<V>

A thread-safe variant of LongArray in which all mutating operations (e.g. add, set) are implemented by making a fresh copy of the underlying array.

Iterators over this LongArray are guaranteed to produce a safe-iteration and not to throw ConcurrentModificationException. The iterator will not reflect concurrent additions, removals, or changes to this array. Mutating operations on iterators themselves (e.g. remove, setValue) are not supported (and will throw UnsupportedOperationException).

Note: mutations on this LongArray are costly, but may be more efficient than alternatives when traversal operations vastly outnumber mutations. All mutating operations are synchronized, so concurrent mutation can be prevented by holding synchronization on this object.

This data-structure is not suitable to frequent updates, or updates on large data-sets see ReadHeavyLongArray for a more suitable alternative for such cases.

Since:

Coherence 3.7

Author:

rhl 2010.09.09

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	CopyOnWriteLongArray.UnmodifiableIterator<V>	Unmodifiable view of a LongArray.Iterator.

Nested classes/interfaces inherited from interface com.tangosol.util.LongArray

LongArray.Iterator<V>

Field Summary

Fields

Modifier and Type	Field	Description
protected static LongArray	EMPTY_ARRAY	An empty placeholder array.

Fields inherited from interface com.tangosol.util.LongArray

NOT_FOUND

Constructor Summary

Constructors

Constructor	Description
CopyOnWriteLongArray()	Default constructor.
CopyOnWriteLongArray(LongArray<V> array)	Construct a CopyOnWriteLongArray, initialized with the contents of the specified LongArray.
CopyOnWriteLongArray(Class<? extends LongArray<V>> clazz)	Construct a CopyOnWriteLongArray with an underlying array of the specified type.

Method Summary

Modifier and Type	Method	Description
long	add(V oValue)	Add the passed element value to the LongArray and return the index at which the element value was stored.
void	clear()	Remove all nodes from the LongArray.
CopyOnWriteLongArray<V>	clone()	Make a clone of the LongArray.
LongArray<V>	copyArray(LongArray<V> array)	Return a shallow copy of the specified LongArray.
protected LongArray<V>	delegate()	Return the internal LongArray.
LongArray.Iterator<V>	instantiateUnmodifiableIterator(LongArray.Iterator<V> iterator)	Factory pattern: instantiate an UnmodifiableIterator.
LongArray.Iterator<V>	iterator()	Obtain a LongArray.Iterator of the contents of the LongArray in order of increasing indices.
LongArray.Iterator<V>	iterator(long lIndex)	Obtain a LongArray.Iterator of the contents of the LongArray in order of increasing indices, starting at a particular index such that the first call to next will set the location of the iterator at the first existent index that is greater than or equal to the specified index, or will throw a NoSuchElementException if there is no such existent index.
V	remove(long lIndex)	Remove the specified index from the LongArray, returning its associated value.
void	remove(long lIndexFrom, long lIndexTo)	Remove all nodes in the specified range.
LongArray.Iterator<V>	reverseIterator()	Obtain a LongArray.Iterator of the contents of the LongArray in reverse order (decreasing indices).
LongArray.Iterator<V>	reverseIterator(long lIndex)	Obtain a LongArray.Iterator of the contents of the LongArray in reverse order (decreasing indices), starting at a particular index such that the first call to next will set the location of the iterator at the first existent index that is less than or equal to the specified index, or will throw a NoSuchElementException if there is no such existent index.
V	set(long lIndex, V oValue)	Add the passed item to the LongArray at the specified index.
protected void	setDelegate(LongArray<V> array)	Set the internal LongArray.

Methods inherited from class com.tangosol.util.WrapperCollections.AbstractWrapperLongArray

ceiling, ceilingIndex, contains, exists, floor, floorIndex, get, getFirstIndex, getLastIndex, getSize, indexOf, indexOf, isEmpty, lastIndexOf, lastIndexOf

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Methods inherited from interface com.tangosol.util.LongArray

equals, keys, toString

Field Detail

EMPTY_ARRAY

protected static final LongArray EMPTY_ARRAY

An empty placeholder array. This array should not be mutated or exposed.

Constructor Detail

CopyOnWriteLongArray

public CopyOnWriteLongArray()

Default constructor.

CopyOnWriteLongArray

public CopyOnWriteLongArray(Class<? extends LongArray<V>> clazz)
                     throws IllegalAccessException,
                            InstantiationException

Construct a CopyOnWriteLongArray with an underlying array of the specified type.

Parameters:

clazz - the type of the internal array; must implement LongArray and have a public no-arg constructor

Throws:

ClassCastException - if the specified type does not implement LongArray

IllegalAccessException - if the class or its no-arg constructor is not accessible

InstantiationException - if the specified Class represents an abstract class or interface; or if the class does not have a no-arg constructor; or if the instantiation fails for some other reason.

CopyOnWriteLongArray

public CopyOnWriteLongArray(LongArray<V> array)

Construct a CopyOnWriteLongArray, initialized with the contents of the specified LongArray.

Parameters:

array - the initial LongArray

Method Detail

delegate

protected LongArray<V> delegate()

Return the internal LongArray.

Specified by:

delegate in class WrapperCollections.AbstractWrapperLongArray<V>

Returns:

the internal LongArray

setDelegate

protected void setDelegate(LongArray<V> array)

Set the internal LongArray.

Parameters:

array - the new internal LongArray

copyArray

public LongArray<V> copyArray(LongArray<V> array)

Return a shallow copy of the specified LongArray.

Parameters:

array - the array to be copied

Returns:

a shallow copy of the specified LongArray

set

public V set(long lIndex,
             V oValue)

Add the passed item to the LongArray at the specified index.

If the index is already used, the passed value will replace the current value stored with the key, and the replaced value will be returned.

It is expected that LongArray implementations will "grow" as necessary to support the specified index.

Specified by:

set in interface LongArray<V>

Overrides:

set in class WrapperCollections.AbstractWrapperLongArray<V>

Parameters:

lIndex - a long index value

oValue - the object to store at the specified index

Returns:

the object that was stored at the specified index, or null

add

public long add(V oValue)

Add the passed element value to the LongArray and return the index at which the element value was stored.

Specified by:

add in interface LongArray<V>

Overrides:

add in class WrapperCollections.AbstractWrapperLongArray<V>

Parameters:

oValue - the object to add to the LongArray

Returns:

the long index value at which the element value was stored

remove

public V remove(long lIndex)

Remove the specified index from the LongArray, returning its associated value.

Specified by:

remove in interface LongArray<V>

Overrides:

remove in class WrapperCollections.AbstractWrapperLongArray<V>

Parameters:

lIndex - the index into the LongArray

Returns:

the associated value (which can be null) or null if the specified index is not in the LongArray

remove

public void remove(long lIndexFrom,
                   long lIndexTo)

Remove all nodes in the specified range.

Specified by:

remove in interface LongArray<V>

Overrides:

remove in class WrapperCollections.AbstractWrapperLongArray<V>

Parameters:

lIndexFrom - the floor index

lIndexTo - the ceiling index (exclusive)

clear

public void clear()

Remove all nodes from the LongArray.

Specified by:

clear in interface LongArray<V>

Overrides:

clear in class WrapperCollections.AbstractWrapperLongArray<V>

iterator

public LongArray.Iterator<V> iterator()

Obtain a LongArray.Iterator of the contents of the LongArray in order of increasing indices.

Specified by:

iterator in interface Iterable<V>

Specified by:

iterator in interface LongArray<V>

Overrides:

iterator in class WrapperCollections.AbstractWrapperLongArray<V>

Returns:

an instance of LongArray.Iterator

iterator

public LongArray.Iterator<V> iterator(long lIndex)

Obtain a LongArray.Iterator of the contents of the LongArray in order of increasing indices, starting at a particular index such that the first call to next will set the location of the iterator at the first existent index that is greater than or equal to the specified index, or will throw a NoSuchElementException if there is no such existent index.

Specified by:

iterator in interface LongArray<V>

Overrides:

iterator in class WrapperCollections.AbstractWrapperLongArray<V>

Parameters:

lIndex - the LongArray index to iterate from

Returns:

an instance of LongArray.Iterator

reverseIterator

public LongArray.Iterator<V> reverseIterator()

Obtain a LongArray.Iterator of the contents of the LongArray in reverse order (decreasing indices).

Specified by:

reverseIterator in interface LongArray<V>

Overrides:

reverseIterator in class WrapperCollections.AbstractWrapperLongArray<V>

Returns:

an instance of LongArray.Iterator

reverseIterator

public LongArray.Iterator<V> reverseIterator(long lIndex)

Obtain a LongArray.Iterator of the contents of the LongArray in reverse order (decreasing indices), starting at a particular index such that the first call to next will set the location of the iterator at the first existent index that is less than or equal to the specified index, or will throw a NoSuchElementException if there is no such existent index.

Specified by:

reverseIterator in interface LongArray<V>

Overrides:

reverseIterator in class WrapperCollections.AbstractWrapperLongArray<V>

Parameters:

lIndex - the LongArray index to iterate from

Returns:

an instance of LongArray.Iterator

clone

public CopyOnWriteLongArray<V> clone()

Make a clone of the LongArray. The element values are not deep-cloned.

Specified by:

clone in interface LongArray<V>

Specified by:

clone in class WrapperCollections.AbstractWrapperLongArray<V>

Returns:

a clone of this LongArray object

instantiateUnmodifiableIterator

public LongArray.Iterator<V> instantiateUnmodifiableIterator(LongArray.Iterator<V> iterator)

Factory pattern: instantiate an UnmodifiableIterator.

Parameters:

iterator - the underlying iterator

Returns:

an UnmodifiableIterator