com.iparelan.util
Class WeakHashSet<T>

java.lang.Object
  com.iparelan.util.WeakHashSet<T>

Type Parameters:

T - The type of objects held in the set.

All Implemented Interfaces:

Cloneable, Iterable<T>, Collection<T>, Set<T>

@Decorator
@Copyright(value="Copyright © 2008, Iparelan Solutions, LLC. All rights reserved.")
public class WeakHashSet<T>
extends Object
implements Set<T>, Cloneable

A type-safe alternative to HashSet that guarantees that objects in the set are not excluded from garbage collection because they are elements of the set.

Version:

July 2008

Author:

Greg Mattes

See Also:

WeakHashSet, "Hardcore Java," Simmons, Chapter 11, "A Weak Collection"

Nested Class Summary

private static class

WeakHashSet.WeakHashSetClassHolder

Field Summary

private Set<T>	delegate
static String	WEAKHASHSET_DELEGATE_CLASSNAME

Constructor Summary

WeakHashSet()
Creates a WeakHashSet

WeakHashSet(Collection<? extends T> collection)
Creates a WeakHashSet

WeakHashSet(int initialCapacity)
Creates a WeakHashSet

WeakHashSet(int initialCapacity, float loadFactor)
Creates a WeakHashSet

Method Summary

boolean	add(T object)
boolean	addAll(Collection<? extends T> collection)
void	clear()
protected WeakHashSet<T>	clone()
boolean	contains(Object object)
boolean	containsAll(Collection collection)
boolean	equals(Object object)
int	hashCode()
boolean	isEmpty()
Iterator<T>	iterator()
boolean	remove(Object object)
boolean	removeAll(Collection collection)
boolean	retainAll(Collection collection)
int	size()
Object[]	toArray()
<T> T[]	toArray(T[] array)
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

delegate

private final Set<T> delegate

WEAKHASHSET_DELEGATE_CLASSNAME

public static final String WEAKHASHSET_DELEGATE_CLASSNAME

See Also:

Constant Field Values

Constructor Detail

WeakHashSet

public WeakHashSet()

Creates a WeakHashSet

WeakHashSet

public WeakHashSet(Collection<? extends T> collection)

Creates a WeakHashSet

Parameters:

collection - see HashSet

WeakHashSet

public WeakHashSet(int initialCapacity,
                   float loadFactor)

Creates a WeakHashSet

Parameters:

initialCapacity - see HashSet

loadFactor - see HashSet

WeakHashSet

public WeakHashSet(int initialCapacity)

Creates a WeakHashSet

Parameters:

initialCapacity - see HashSet

Method Detail

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Collection<T>

Specified by:

isEmpty in interface Set<T>

add

public boolean add(T object)

Specified by:

add in interface Collection<T>

Specified by:

add in interface Set<T>

addAll

public boolean addAll(Collection<? extends T> collection)

Specified by:

addAll in interface Collection<T>

Specified by:

addAll in interface Set<T>

clear

public void clear()

Specified by:

clear in interface Collection<T>

Specified by:

clear in interface Set<T>

contains

public boolean contains(Object object)

Specified by:

contains in interface Collection<T>

Specified by:

contains in interface Set<T>

containsAll

public boolean containsAll(Collection collection)

Specified by:

containsAll in interface Collection<T>

Specified by:

containsAll in interface Set<T>

equals

public boolean equals(Object object)

Specified by:

equals in interface Collection<T>

Specified by:

equals in interface Set<T>

Overrides:

equals in class Object

hashCode

public int hashCode()

Specified by:

hashCode in interface Collection<T>

Specified by:

hashCode in interface Set<T>

Overrides:

hashCode in class Object

iterator

public Iterator<T> iterator()

Specified by:

iterator in interface Iterable<T>

Specified by:

iterator in interface Collection<T>

Specified by:

iterator in interface Set<T>

remove

public boolean remove(Object object)

Specified by:

remove in interface Collection<T>

Specified by:

remove in interface Set<T>

removeAll

public boolean removeAll(Collection collection)

Specified by:

removeAll in interface Collection<T>

Specified by:

removeAll in interface Set<T>

retainAll

public boolean retainAll(Collection collection)

Specified by:

retainAll in interface Collection<T>

Specified by:

retainAll in interface Set<T>

size

public int size()

Specified by:

size in interface Collection<T>

Specified by:

size in interface Set<T>

toArray

public Object[] toArray()

Specified by:

toArray in interface Collection<T>

Specified by:

toArray in interface Set<T>

toArray

public <T> T[] toArray(T[] array)

Specified by:

toArray in interface Collection<T>

Specified by:

toArray in interface Set<T>

toString

public String toString()

Overrides:

toString in class Object

clone

protected WeakHashSet<T> clone()
                        throws CloneNotSupportedException

Overrides:

clone in class Object

Throws:

CloneNotSupportedException