com.badlogic.gdx.utils

Class IntSet

java.lang.Object

com.badlogic.gdx.utils.IntSet

public class IntSet
extends Object

An unordered set that uses int keys. This implementation uses cuckoo hashing using 3 hashes, random walking, and a small stash for problematic keys. No allocation is done except when growing the table size.

This set performs very fast contains and remove (typically O(1), worst case O(log(n))). Add may be a bit slower, depending on hash collisions. Load factors greater than 0.91 greatly increase the chances the set will have to rehash to the next higher POT size.

Author:

Nathan Sweet

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	IntSet.IntSetIterator

Field Summary

Fields

Modifier and Type	Field and Description
int	size

Constructor Summary

Constructors

Constructor and Description
IntSet() Creates a new sets with an initial capacity of 32 and a load factor of 0.8.
IntSet(int initialCapacity) Creates a new set with a load factor of 0.8.
IntSet(int initialCapacity, float loadFactor) Creates a new set with the specified initial capacity and load factor.
IntSet(IntSet map) Creates a new map identical to the specified map.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	add(int key) Returns true if the key was not already in the set.
void	addAll(int... array)
void	addAll(int[] array, int offset, int length)
void	addAll(IntArray array)
void	addAll(IntArray array, int offset, int length)
void	addAll(IntSet set)
void	clear()
void	clear(int maximumCapacity) Clears the map and reduces the size of the backing arrays to be the specified capacity if they are larger.
boolean	contains(int key)
void	ensureCapacity(int additionalCapacity) Increases the size of the backing array to accommodate the specified number of additional items.
int	first()
IntSet.IntSetIterator	iterator() Returns an iterator for the keys in the set.
boolean	remove(int key) Returns true if the key was removed.
void	shrink(int maximumCapacity) Reduces the size of the backing arrays to be the specified capacity or less.
String	toString()
static IntSet	with(int... array)

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

size

public int size

Constructor Detail

IntSet

public IntSet()

Creates a new sets with an initial capacity of 32 and a load factor of 0.8. This set will hold 25 items before growing the backing table.

IntSet

public IntSet(int initialCapacity)

Creates a new set with a load factor of 0.8. This set will hold initialCapacity * 0.8 items before growing the backing table.

IntSet

public IntSet(int initialCapacity,
      float loadFactor)

Creates a new set with the specified initial capacity and load factor. This set will hold initialCapacity * loadFactor items before growing the backing table.

IntSet

public IntSet(IntSet map)

Creates a new map identical to the specified map.

Method Detail

add

public boolean add(int key)

Returns true if the key was not already in the set.

addAll

public void addAll(IntArray array)

addAll

public void addAll(IntArray array,
          int offset,
          int length)

addAll

public void addAll(int... array)

addAll

public void addAll(int[] array,
          int offset,
          int length)

addAll

public void addAll(IntSet set)

remove

public boolean remove(int key)

Returns true if the key was removed.

shrink

public void shrink(int maximumCapacity)

Reduces the size of the backing arrays to be the specified capacity or less. If the capacity is already less, nothing is done. If the set contains more items than the specified capacity, the next highest power of two capacity is used instead.

clear

public void clear(int maximumCapacity)

Clears the map and reduces the size of the backing arrays to be the specified capacity if they are larger.

clear

public void clear()

contains

public boolean contains(int key)

first

public int first()

ensureCapacity

public void ensureCapacity(int additionalCapacity)

Increases the size of the backing array to accommodate the specified number of additional items. Useful before adding many items to avoid multiple backing array resizes.

toString

public String toString()

Overrides:

toString in class Object

iterator

public IntSet.IntSetIterator iterator()

Returns an iterator for the keys in the set. Remove is supported. Note that the same iterator instance is returned each time this method is called. Use the IntSet.IntSetIterator constructor for nested or multithreaded iteration.

with

public static IntSet with(int... array)