it.unimi.dsi.fastutil.ints

Class IntArraySet

java.lang.Object

java.util.AbstractCollection<java.lang.Integer>

it.unimi.dsi.fastutil.ints.AbstractIntCollection

it.unimi.dsi.fastutil.ints.AbstractIntSet

it.unimi.dsi.fastutil.ints.IntArraySet

All Implemented Interfaces:

it.unimi.dsi.fastutil.ints.IntCollection, it.unimi.dsi.fastutil.ints.IntIterable, IntSet, java.io.Serializable, java.lang.Cloneable, java.lang.Iterable<java.lang.Integer>, java.util.Collection<java.lang.Integer>, java.util.Set<java.lang.Integer>

public class IntArraySet
extends AbstractIntSet
implements java.io.Serializable, java.lang.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

Field Summary

Fields

Modifier and Type	Field and Description
protected int[]	a The backing array (valid up to size, excluded).
protected int	size The number of valid entries in a.

Constructor Summary

Constructors

Constructor and Description
IntArraySet() Creates a new empty array set.
IntArraySet(java.util.Collection<? extends java.lang.Integer> c) Creates a new array set copying the contents of a given 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(it.unimi.dsi.fastutil.ints.IntCollection c) Creates a new array set copying the contents of a given collection.
IntArraySet(IntSet c) Creates a new array set copying the contents of a given collection.
IntArraySet(java.util.Set<? extends java.lang.Integer> c) Creates a new array set copying the contents of a given set.

Method Summary

Modifier and Type	Method and Description
boolean	add(int k)
void	clear()
IntArraySet	clone() Returns a deep copy of this set.
boolean	contains(int k)
boolean	isEmpty()
it.unimi.dsi.fastutil.ints.IntIterator	iterator() Returns a type-specific iterator on the elements of this set.
static IntArraySet	of() Creates a new empty array set.
static IntArraySet	of(int... a) Creates a new array set using an array of elements.
static IntArraySet	of(int e) Creates a new array set using the element given.
static IntArraySet	ofUnchecked() Creates a new empty array set.
static IntArraySet	ofUnchecked(int... a) Creates a new array set using an array of elements.
boolean	remove(int k) Removes an element from this set.
int	size()
it.unimi.dsi.fastutil.ints.IntSpliterator	spliterator() Returns a type-specific spliterator on the elements of this set.
int[]	toArray(int[] a)
int[]	toIntArray()

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, addAll, contains, containsAll, containsAll, forEach, remove, removeAll, removeAll, removeIf, retainAll, retainAll, toIntArray, toString

Methods inherited from class java.util.AbstractCollection

toArray, toArray

Methods inherited from class java.lang.Object

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

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

add, contains, of, of, remove

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

addAll, containsAll, intIterator, intParallelStream, intSpliterator, intStream, parallelStream, removeAll, removeIf, removeIf, removeIf, retainAll, stream, toIntArray

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

forEach, forEach, forEach

Methods inherited from interface java.util.Set

addAll, containsAll, removeAll, retainAll, toArray, toArray

Field Detail

a

protected transient int[] a

The backing array (valid up to size, excluded).

size

protected int size

The number of valid entries in a.

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 the responsibility of the caller to ensure 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(it.unimi.dsi.fastutil.ints.IntCollection c)

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

Parameters:

c - a collection.

IntArraySet

public IntArraySet(java.util.Collection<? extends java.lang.Integer> c)

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

Parameters:

c - a collection.

IntArraySet

public IntArraySet(IntSet c)

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

Parameters:

c - a collection.

IntArraySet

public IntArraySet(java.util.Set<? extends java.lang.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 the responsibility of the caller to ensure that the first size elements of a are distinct.

Parameters:

a - the backing array.

size - the number of valid elements in a.

Method Detail

of

public static IntArraySet of()

Creates a new empty array set.

Specified by:

of in interface IntSet

Returns:

a new empty array set.

of

public static IntArraySet of(int e)

Creates a new array set using the element given.

Specified by:

of in interface IntSet

Parameters:

e - the element that the returned set will contain.

Returns:

a new array set containing e.

of

public static IntArraySet of(int... a)

Creates a new array set using an array of elements.

Unlike the array accepting constructors, this method will throw if duplicate elements are encountered. This adds a non-trivial validation burden. Use ofUnchecked() if you know your input has no duplicates, which will skip this validation.

Specified by:

of in interface IntSet

Parameters:

a - the backing array of the returned array set.

Returns:

a new array set containing the elements in a.

Throws:

java.lang.IllegalArgumentException - if there were duplicate entries.

ofUnchecked

public static IntArraySet ofUnchecked()

Creates a new empty array set.

Returns:

a new empty array set.

ofUnchecked

public static IntArraySet ofUnchecked(int... a)

Creates a new array set using an array of elements.

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

Parameters:

a - the backing array of the returned array set.

Returns:

a new array set containing the elements in a.

iterator

public it.unimi.dsi.fastutil.ints.IntIterator iterator()

Description copied from interface: IntSet

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

Specified by:

iterator in interface it.unimi.dsi.fastutil.ints.IntCollection

Specified by:

iterator in interface it.unimi.dsi.fastutil.ints.IntIterable

Specified by:

iterator in interface IntSet

Specified by:

iterator in interface java.lang.Iterable<java.lang.Integer>

Specified by:

iterator in interface java.util.Collection<java.lang.Integer>

Specified by:

iterator in interface java.util.Set<java.lang.Integer>

Specified by:

iterator in class AbstractIntSet

Returns:

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

spliterator

public it.unimi.dsi.fastutil.ints.IntSpliterator spliterator()

Returns a type-specific spliterator on the elements of this set.

Set spliterators must report at least Spliterator.DISTINCT.

See Set.spliterator() for more documentation on the requirements of the returned spliterator.

In addition to the usual trait of DISTINCT for sets, the returned spliterator will also report the trait ORDERED.

The returned spliterator is late-binding; it will track structural changes after the current item, up until the first trySplit(), at which point the maximum index will be fixed.
Structural changes before the current item or after the first trySplit() will result in unspecified behavior.

Specified by:

spliterator in interface it.unimi.dsi.fastutil.ints.IntCollection

Specified by:

spliterator in interface it.unimi.dsi.fastutil.ints.IntIterable

Specified by:

spliterator in interface IntSet

Specified by:

spliterator in interface java.lang.Iterable<java.lang.Integer>

Specified by:

spliterator in interface java.util.Collection<java.lang.Integer>

Specified by:

spliterator in interface java.util.Set<java.lang.Integer>

Returns:

contains

public boolean contains(int k)

Specified by:

contains in interface it.unimi.dsi.fastutil.ints.IntCollection

Overrides:

contains in class it.unimi.dsi.fastutil.ints.AbstractIntCollection

size

public int size()

Specified by:

size in interface java.util.Collection<java.lang.Integer>

Specified by:

size in interface java.util.Set<java.lang.Integer>

Specified by:

size in class java.util.AbstractCollection<java.lang.Integer>

remove

public boolean remove(int k)

Description copied from class: AbstractIntSet

Removes an element from this set. 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)

Specified by:

add in interface it.unimi.dsi.fastutil.ints.IntCollection

Overrides:

add in class it.unimi.dsi.fastutil.ints.AbstractIntCollection

clear

public void clear()

Specified by:

clear in interface java.util.Collection<java.lang.Integer>

Specified by:

clear in interface java.util.Set<java.lang.Integer>

Overrides:

clear in class java.util.AbstractCollection<java.lang.Integer>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface java.util.Collection<java.lang.Integer>

Specified by:

isEmpty in interface java.util.Set<java.lang.Integer>

Overrides:

isEmpty in class java.util.AbstractCollection<java.lang.Integer>

toIntArray

public int[] toIntArray()

Specified by:

toIntArray in interface it.unimi.dsi.fastutil.ints.IntCollection

Overrides:

toIntArray in class it.unimi.dsi.fastutil.ints.AbstractIntCollection

toArray

public int[] toArray(int[] a)

Specified by:

toArray in interface it.unimi.dsi.fastutil.ints.IntCollection

Overrides:

toArray in class it.unimi.dsi.fastutil.ints.AbstractIntCollection

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.

Overrides:

clone in class java.lang.Object

Returns:

a deep copy of this set.