Package it.unimi.dsi.fastutil.ints

Class IntArraySet

java.lang.Object

java.util.AbstractCollection<Integer>

it.unimi.dsi.fastutil.ints.AbstractIntCollection

it.unimi.dsi.fastutil.ints.AbstractIntSet

it.unimi.dsi.fastutil.ints.IntArraySet

All Implemented Interfaces:

IntCollection, IntIterable, IntSet, Serializable, Cloneable, Iterable<Integer>, Collection<Integer>, Set<Integer>

public class IntArraySet
extends AbstractIntSet
implements Serializable, Cloneable

A simple, brute-force implementation of a set based on a backing array.

The main purpose of this implementation is that of wrapping cleanly the brute-force approach to the storage of a very small number of items: just put them into an array and scan linearly to find an item.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
IntArraySet()	Creates a new empty array set.
IntArraySet(int capacity)	Creates a new empty array set of given initial capacity.
IntArraySet(int[] a)	Creates a new array set using the given backing array.
IntArraySet(int[] a, int size)	Creates a new array set using the given backing array and the given number of elements of the array.
IntArraySet(IntCollection c)	Creates a new array set copying the contents of a given collection.
IntArraySet(Collection<? extends Integer> c)	Creates a new array set copying the contents of a given set.

Method Summary

Modifier and Type	Method	Description
boolean	add(int k)	Ensures that this collection contains the specified element (optional operation).
void	clear()
IntArraySet	clone()	Returns a deep copy of this set.
boolean	contains(int k)	Returns true if this collection contains the specified element.
boolean	isEmpty()
IntIterator	iterator()	Returns a type-specific iterator on the elements of this collection.
boolean	remove(int k)	Removes an element from this set.
int	size()

Methods inherited from class it.unimi.dsi.fastutil.ints.AbstractIntSet

equals, hashCode, rem

Methods inherited from class it.unimi.dsi.fastutil.ints.AbstractIntCollection

add, addAll, contains, containsAll, remove, removeAll, retainAll, toArray, toIntArray, toIntArray, toString

Methods inherited from class java.util.AbstractCollection

addAll, containsAll, removeAll, retainAll, toArray, toArray

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Collection

parallelStream, stream, toArray

Methods inherited from interface it.unimi.dsi.fastutil.ints.IntCollection

addAll, containsAll, removeAll, removeIf, removeIf, retainAll, toArray, toIntArray, toIntArray

Methods inherited from interface it.unimi.dsi.fastutil.ints.IntIterable

forEach, forEach

Methods inherited from interface it.unimi.dsi.fastutil.ints.IntSet

add, contains, remove

Methods inherited from interface java.util.Set

addAll, containsAll, removeAll, retainAll, spliterator, toArray, toArray

Constructor Detail

IntArraySet

public IntArraySet(int[] a)

Creates a new array set using the given backing array. The resulting set will have as many elements as the array.

It is responsibility of the caller that the elements of a are distinct.

Parameters:

a - the backing array.

IntArraySet

public IntArraySet()

Creates a new empty array set.

IntArraySet

public IntArraySet(int capacity)

Creates a new empty array set of given initial capacity.

Parameters:

capacity - the initial capacity.

IntArraySet

public IntArraySet(IntCollection c)

Creates a new array set copying the contents of a given collection.

Parameters:

c - a collection.

IntArraySet

public IntArraySet(Collection<? extends Integer> c)

Creates a new array set copying the contents of a given set.

Parameters:

c - a collection.

IntArraySet

public IntArraySet(int[] a,
                   int size)

Creates a new array set using the given backing array and the given number of elements of the array.

It is responsibility of the caller that the first size elements of a are distinct.

Parameters:

a - the backing array.

size - the number of valid elements in a.

Method Detail

iterator

public IntIterator iterator()

Description copied from interface: IntCollection

Returns a type-specific iterator on the elements of this collection.

Note that this specification strengthens the one given in Iterable.iterator(), which was already strengthened in the corresponding type-specific class, but was weakened by the fact that this interface extends Collection.

Specified by:

iterator in interface Collection<Integer>

Specified by:

iterator in interface IntCollection

Specified by:

iterator in interface IntIterable

Specified by:

iterator in interface IntSet

Specified by:

iterator in interface Iterable<Integer>

Specified by:

iterator in interface Set<Integer>

Specified by:

iterator in class AbstractIntSet

Returns:

a type-specific iterator on the elements of this collection.

See Also:

Iterable.iterator()

contains

public boolean contains(int k)

Description copied from class: AbstractIntCollection

Returns true if this collection contains the specified element.

This implementation iterates over the elements in the collection, looking for the specified element.

Specified by:

contains in interface IntCollection

Overrides:

contains in class AbstractIntCollection

See Also:

Collection.contains(Object)

size

public int size()

Specified by:

size in interface Collection<Integer>

Specified by:

size in interface Set<Integer>

Specified by:

size in class AbstractCollection<Integer>

remove

public boolean remove(int k)

Description copied from class: AbstractIntSet

Removes an element from this set.

Note that the corresponding method of a type-specific collection is rem(). This unfortunate situation is caused by the clash with the similarly named index-based method in the List interface. Delegates to the type-specific rem() method implemented by type-specific abstract Collection superclass.

Specified by:

remove in interface IntSet

Overrides:

remove in class AbstractIntSet

See Also:

Collection.remove(Object)

add

public boolean add(int k)

Description copied from class: AbstractIntCollection

Ensures that this collection contains the specified element (optional operation).

This implementation always throws an UnsupportedOperationException.

Specified by:

add in interface IntCollection

Overrides:

add in class AbstractIntCollection

See Also:

Collection.add(Object)

clear

public void clear()

Specified by:

clear in interface Collection<Integer>

Specified by:

clear in interface Set<Integer>

Overrides:

clear in class AbstractCollection<Integer>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Collection<Integer>

Specified by:

isEmpty in interface Set<Integer>

Overrides:

isEmpty in class AbstractCollection<Integer>

clone

public IntArraySet clone()

Returns a deep copy of this set.

This method performs a deep copy of this array set; the data stored in the set, however, is not cloned. Note that this makes a difference only for object keys.

Returns:

a deep copy of this set.