Package com.tangosol.util

Class OpenHashSet<E>

java.lang.Object

java.util.AbstractCollection<E>

java.util.AbstractSet<E>

com.tangosol.util.OpenHashSet<E>

Type Parameters:

E - the type of elements that can be managed by this set

All Implemented Interfaces:

Iterable<E>, Collection<E>, Set<E>

public class OpenHashSet<E>
extends AbstractSet<E>

An implementation of Set that is optimized for memory footprint. Specifically, instead of delegating to a HashMap which instantiates an "Entry" object for each element (as the HashSet does, which references those entries in a linked list fashion with the head of the linked list stored in the hash bucket array, this implementation stores its elements using an open hashing algorithm, i.e. the elements are stored directly in the hash bucket array.

This implementation is explicitly NOT thread-safe.

Since:

12.2.1

Author:

cp 2013.01.15

Constructor Summary

Constructors

Constructor	Description
OpenHashSet()	Default constructor.
OpenHashSet(int initialCapacity)	Create a OpenHashSet pre-sized to hold the specified number of elements.
OpenHashSet(Collection<? extends E> coll)	Create a OpenHashSet that will initially contain the contents of the passed Collection.

Method Summary

Modifier and Type	Method	Description
boolean	add(E e)
void	clear()
boolean	contains(Object o)
protected E	getElement(int n)	Expose the indexed element storage to sub-classes in a range-unsafe manner.
Iterator<E>	iterator()
boolean	remove(Object o)
int	size()
Object[]	toArray()
<T> T[]	toArray(T[] a)

Methods inherited from class java.util.AbstractSet

equals, hashCode, removeAll

Methods inherited from class java.util.AbstractCollection

addAll, containsAll, isEmpty, retainAll, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Collection

parallelStream, removeIf, stream, toArray

Methods inherited from interface java.lang.Iterable

forEach

Methods inherited from interface java.util.Set

addAll, containsAll, isEmpty, retainAll, spliterator

Constructor Details

OpenHashSet

public OpenHashSet()

Default constructor.

OpenHashSet

public OpenHashSet(int initialCapacity)

Create a OpenHashSet pre-sized to hold the specified number of elements.

Parameters:

initialCapacity - the initial capacity requirement for the hash set

OpenHashSet

public OpenHashSet(Collection<? extends E> coll)

Create a OpenHashSet that will initially contain the contents of the passed Collection. In other words, this is a "copy constructor".

Parameters:

coll - the Collection whose contents this

Method Details

size

public int size()

Specified by:

size in interface Collection<E>

Specified by:

size in interface Set<E>

Specified by:

size in class AbstractCollection<E>

contains

public boolean contains(Object o)

Specified by:

contains in interface Collection<E>

Specified by:

contains in interface Set<E>

Overrides:

contains in class AbstractCollection<E>

add

public boolean add(E e)

Specified by:

add in interface Collection<E>

Specified by:

add in interface Set<E>

Overrides:

add in class AbstractCollection<E>

remove

public boolean remove(Object o)

Specified by:

remove in interface Collection<E>

Specified by:

remove in interface Set<E>

Overrides:

remove in class AbstractCollection<E>

clear

public void clear()

Specified by:

clear in interface Collection<E>

Specified by:

clear in interface Set<E>

Overrides:

clear in class AbstractCollection<E>

iterator

public Iterator<E> iterator()

Specified by:

iterator in interface Collection<E>

Specified by:

iterator in interface Iterable<E>

Specified by:

iterator in interface Set<E>

Specified by:

iterator in class AbstractCollection<E>

toArray

public Object[] toArray()

Specified by:

toArray in interface Collection<E>

Specified by:

toArray in interface Set<E>

Overrides:

toArray in class AbstractCollection<E>

toArray

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

Specified by:

toArray in interface Collection<E>

Specified by:

toArray in interface Set<E>

Overrides:

toArray in class AbstractCollection<E>

getElement

protected E getElement(int n)

Expose the indexed element storage to sub-classes in a range-unsafe manner.

Parameters:

n - an element index

Returns:

the value stored at the specified index; note that a null value is not differentiable from an empty element, since both are returned as null