org.cell2d.util

Class ArrayMap<K,V>

java.lang.Object

org.cell2d.util.ArrayMap<K,V>

Type Parameters:

K - The type of keys maintained by this ArrayMap

V - The type of mapped values

All Implemented Interfaces:

java.util.Map<K,V>

public class ArrayMap<K,V>
extends java.lang.Object
implements java.util.Map<K,V>

An ArrayMap is a Map implemented as a resizable array, just like that of an ArrayList. An ArrayMap takes up less memory than other Map types, and offers at-least-comparable performance to a HashMap when the Map size is very small. For best results, the initial capacity of an ArrayMap should be set to the smallest number that the ArrayMap's size will almost certainly never exceed.

See Also:

ArrayList

Constructor Summary

Constructors

Constructor and Description
ArrayMap() Constructs an empty ArrayMap with an initial capacity of 10.
ArrayMap(int initialCapacity) Constructs an empty ArrayMap with the specified initial capacity.
ArrayMap(java.util.Map<? extends K,? extends V> m) Constructs an ArrayMap with the same mappings as the specified Map.

Method Summary

Modifier and Type	Method and Description
void	clear()
boolean	containsKey(java.lang.Object key)
boolean	containsValue(java.lang.Object value)
void	ensureCapacity(int minCapacity) Increases the capacity of this ArrayMap, if necessary, to be at least the specified minimum capacity.
java.util.Set<java.util.Map.Entry<K,V>>	entrySet()
V	get(java.lang.Object key)
boolean	isEmpty()
java.util.Set<K>	keySet()
V	put(K key, V value)
void	putAll(java.util.Map<? extends K,? extends V> m)
V	remove(java.lang.Object key)
int	size()
void	trimToSize() Trims the capacity of this ArrayMap to be equal to its current size.
java.util.Collection<V>	values()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.Map

compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, putIfAbsent, remove, replace, replace, replaceAll

Constructor Detail

ArrayMap

public ArrayMap(int initialCapacity)

Constructs an empty ArrayMap with the specified initial capacity.

Parameters:

initialCapacity - The initial capacity of the ArrayMap

ArrayMap

public ArrayMap()

Constructs an empty ArrayMap with an initial capacity of 10.

ArrayMap

public ArrayMap(java.util.Map<? extends K,? extends V> m)

Constructs an ArrayMap with the same mappings as the specified Map. The ArrayMap is created with enough initial capacity to hold these mappings.

Parameters:

m - The Map whose mappings are to be placed into this ArrayMap

Method Detail

size

public int size()

Specified by:

size in interface java.util.Map<K,V>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface java.util.Map<K,V>

containsKey

public boolean containsKey(java.lang.Object key)

Specified by:

containsKey in interface java.util.Map<K,V>

containsValue

public boolean containsValue(java.lang.Object value)

Specified by:

containsValue in interface java.util.Map<K,V>

get

public V get(java.lang.Object key)

Specified by:

get in interface java.util.Map<K,V>

put

public V put(K key,
             V value)

Specified by:

put in interface java.util.Map<K,V>

remove

public V remove(java.lang.Object key)

Specified by:

remove in interface java.util.Map<K,V>

putAll

public void putAll(java.util.Map<? extends K,? extends V> m)

Specified by:

putAll in interface java.util.Map<K,V>

clear

public void clear()

Specified by:

clear in interface java.util.Map<K,V>

keySet

public java.util.Set<K> keySet()

Specified by:

keySet in interface java.util.Map<K,V>

values

public java.util.Collection<V> values()

Specified by:

values in interface java.util.Map<K,V>

entrySet

public java.util.Set<java.util.Map.Entry<K,V>> entrySet()

Specified by:

entrySet in interface java.util.Map<K,V>

trimToSize

public final void trimToSize()

Trims the capacity of this ArrayMap to be equal to its current size. This operation runs in time proportional to the ArrayMap's size, but it minimizes the amount of memory taken up by the ArrayMap.

ensureCapacity

public final void ensureCapacity(int minCapacity)

Increases the capacity of this ArrayMap, if necessary, to be at least the specified minimum capacity.

Parameters:

minCapacity - The minimum capacity that this ArrayMap should have