com.badlogic.gdx.utils

Class ObjectFloatMap<K>

java.lang.Object

com.badlogic.gdx.utils.ObjectFloatMap<K>

All Implemented Interfaces:

Iterable<ObjectFloatMap.Entry<K>>

public class ObjectFloatMap<K>
extends Object
implements Iterable<ObjectFloatMap.Entry<K>>

An unordered map where the values are floats. This implementation is a cuckoo hash map using 3 hashes, random walking, and a small stash for problematic keys. Null keys are not allowed. No allocation is done except when growing the table size.

This map performs very fast get, containsKey, and remove (typically O(1), worst case O(log(n))). Put may be a bit slower, depending on hash collisions. Load factors greater than 0.91 greatly increase the chances the map 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	ObjectFloatMap.Entries<K>
static class	ObjectFloatMap.Entry<K>
static class	ObjectFloatMap.Keys<K>
static class	ObjectFloatMap.Values

Field Summary

Fields

Modifier and Type	Field and Description
int	size

Constructor Summary

Constructors

Constructor and Description
ObjectFloatMap() Creates a new map with an initial capacity of 51 and a load factor of 0.8.
ObjectFloatMap(int initialCapacity) Creates a new map with a load factor of 0.8.
ObjectFloatMap(int initialCapacity, float loadFactor) Creates a new map with the specified initial capacity and load factor.
ObjectFloatMap(ObjectFloatMap<? extends K> map) Creates a new map identical to the specified map.

Method Summary

Modifier and Type	Method and Description
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	containsKey(K key)
boolean	containsValue(float value) Returns true if the specified value is in the map.
void	ensureCapacity(int additionalCapacity) Increases the size of the backing array to accommodate the specified number of additional items.
ObjectFloatMap.Entries<K>	entries() Returns an iterator for the entries in the map.
boolean	equals(Object obj)
K	findKey(float value) Returns the key for the specified value, or null if it is not in the map.
float	get(K key, float defaultValue)
float	getAndIncrement(K key, float defaultValue, float increment) Returns the key's current value and increments the stored value.
int	hashCode()
boolean	isEmpty() Returns true if the map is empty.
ObjectFloatMap.Entries<K>	iterator()
ObjectFloatMap.Keys<K>	keys() Returns an iterator for the keys in the map.
boolean	notEmpty() Returns true if the map has one or more items.
void	put(K key, float value)
void	putAll(ObjectFloatMap<? extends K> map)
float	remove(K key, float defaultValue)
void	shrink(int maximumCapacity) Reduces the size of the backing arrays to be the specified capacity or less.
String	toString()
ObjectFloatMap.Values	values() Returns an iterator for the values in the map.

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

size

public int size

Constructor Detail

ObjectFloatMap

public ObjectFloatMap()

Creates a new map with an initial capacity of 51 and a load factor of 0.8.

ObjectFloatMap

public ObjectFloatMap(int initialCapacity)

Creates a new map with a load factor of 0.8.

Parameters:

initialCapacity - If not a power of two, it is increased to the next nearest power of two.

ObjectFloatMap

public ObjectFloatMap(int initialCapacity,
                      float loadFactor)

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

Parameters:

initialCapacity - If not a power of two, it is increased to the next nearest power of two.

ObjectFloatMap

public ObjectFloatMap(ObjectFloatMap<? extends K> map)

Creates a new map identical to the specified map.

Method Detail

put

public void put(K key,
                float value)

putAll

public void putAll(ObjectFloatMap<? extends K> map)

get

public float get(K key,
                 float defaultValue)

Parameters:

defaultValue - Returned if the key was not associated with a value.

getAndIncrement

public float getAndIncrement(K key,
                             float defaultValue,
                             float increment)

Returns the key's current value and increments the stored value. If the key is not in the map, defaultValue + increment is put into the map.

remove

public float remove(K key,
                    float defaultValue)

notEmpty

public boolean notEmpty()

Returns true if the map has one or more items.

isEmpty

public boolean isEmpty()

Returns true if the map is empty.

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 map 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()

containsValue

public boolean containsValue(float value)

Returns true if the specified value is in the map. Note this traverses the entire map and compares every value, which may be an expensive operation.

containsKey

public boolean containsKey(K key)

findKey

public K findKey(float value)

Returns the key for the specified value, or null if it is not in the map. Note this traverses the entire map and compares every value, which may be an expensive operation.

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.

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object

iterator

public ObjectFloatMap.Entries<K> iterator()

Specified by:

iterator in interface Iterable<ObjectFloatMap.Entry<K>>

entries

public ObjectFloatMap.Entries<K> entries()

Returns an iterator for the entries in the map. Remove is supported.

If Collections.allocateIterators is false, the same iterator instance is returned each time this method is called. Use the ObjectFloatMap.Entries constructor for nested or multithreaded iteration.

values

public ObjectFloatMap.Values values()

Returns an iterator for the values in the map. Remove is supported.

If Collections.allocateIterators is false, the same iterator instance is returned each time this method is called. Use the ObjectFloatMap.Entries constructor for nested or multithreaded iteration.

keys

public ObjectFloatMap.Keys<K> keys()

Returns an iterator for the keys in the map. Remove is supported.

If Collections.allocateIterators is false, the same iterator instance is returned each time this method is called. Use the ObjectFloatMap.Entries constructor for nested or multithreaded iteration.