Package co.aikar.util

Class LoadingMap<K,V>

java.lang.Object

java.util.AbstractMap<K,V>

co.aikar.util.LoadingMap<K,V>

Type Parameters:

K - Key

V - Value

All Implemented Interfaces:

java.util.Map<K,V>

public class LoadingMap<K,V>
extends java.util.AbstractMap<K,V>

Allows you to pass a Loader function that when a key is accessed that doesn't exists, automatically loads the entry into the map by calling the loader Function. .get() Will only return null if the Loader can return null. You may pass any backing Map to use. This class is not thread safe and should be wrapped with Collections.synchronizedMap on the OUTSIDE of the LoadingMap if needed. Do not wrap the backing map with Collections.synchronizedMap.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	LoadingMap.Feeder<T>	Due to java stuff, you will need to cast it to (Function) for some cases

Nested classes/interfaces inherited from class java.util.AbstractMap

java.util.AbstractMap.SimpleEntry<K extends java.lang.Object,V extends java.lang.Object>, java.util.AbstractMap.SimpleImmutableEntry<K extends java.lang.Object,V extends java.lang.Object>

Nested classes/interfaces inherited from interface java.util.Map

java.util.Map.Entry<K extends java.lang.Object,V extends java.lang.Object>

Constructor Summary

Constructors

Constructor	Description
LoadingMap(java.util.Map<K,V> backingMap, com.google.common.base.Function<K,V> loader)	Initializes an auto loading map using specified loader and backing map

Method Summary

Modifier and Type	Method	Description
void	clear()
LoadingMap<K,V>	clone()
boolean	containsKey(java.lang.Object key)
boolean	containsValue(java.lang.Object value)
java.util.Set<java.util.Map.Entry<K,V>>	entrySet()
boolean	equals(java.lang.Object o)
V	get(java.lang.Object key)
int	hashCode()
boolean	isEmpty()
java.util.Set<K>	keySet()
static <K,V> java.util.Map<K,V>	newAutoMap(java.util.Map<K,V> backingMap, java.lang.Class<? extends K> keyClass, java.lang.Class<? extends V> valueClass)	Creates a LoadingMap with an auto instantiating loader.
static <K,V> java.util.Map<K,V>	newAutoMap(java.util.Map<K,V> backingMap, java.lang.Class<? extends V> valueClass)	Creates a LoadingMap with an auto instantiating loader.
static <K,V> java.util.Map<K,V>	newHashAutoMap(java.lang.Class<? extends K> keyClass, java.lang.Class<? extends V> valueClass)
static <K,V> java.util.Map<K,V>	newHashAutoMap(java.lang.Class<? extends K> keyClass, java.lang.Class<? extends V> valueClass, int initialCapacity, float loadFactor)
static <K,V> java.util.Map<K,V>	newHashAutoMap(java.lang.Class<? extends V> valueClass)
static <K,V> java.util.Map<K,V>	newHashAutoMap(java.lang.Class<? extends V> valueClass, int initialCapacity, float loadFactor)
static <K,V> java.util.Map<K,V>	newHashMap(com.google.common.base.Function<K,V> loader)	Initializes an auto loading map using a HashMap
static <K,V> java.util.Map<K,V>	newHashMap(com.google.common.base.Function<K,V> loader, int initialCapacity, float loadFactor)	Initializes an auto loading map using a HashMap
static <K,V> java.util.Map<K,V>	newIdentityHashMap(com.google.common.base.Function<K,V> loader)	Initializes an auto loading map using an Identity HashMap
static <K,V> java.util.Map<K,V>	newIdentityHashMap(com.google.common.base.Function<K,V> loader, int initialCapacity)	Initializes an auto loading map using an Identity HashMap
static <K,V> java.util.Map<K,V>	of(java.util.Map<K,V> backingMap, com.google.common.base.Function<K,V> loader)	Creates a new LoadingMap with the specified map and loader
V	put(K key, V value)
void	putAll(java.util.Map<? extends K,? extends V> m)
V	remove(java.lang.Object key)
int	size()
java.util.Collection<V>	values()

Methods inherited from class java.util.AbstractMap

toString

Methods inherited from interface java.util.Map

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

Methods inherited from class java.lang.Object

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

Constructor Detail

LoadingMap

public LoadingMap(java.util.Map<K,V> backingMap,
                  com.google.common.base.Function<K,V> loader)

Initializes an auto loading map using specified loader and backing map

Parameters:

backingMap - Map to wrap

loader - Loader

Method Detail

of

public static <K,V> java.util.Map<K,V> of(java.util.Map<K,V> backingMap,
                                          com.google.common.base.Function<K,V> loader)

Creates a new LoadingMap with the specified map and loader

Type Parameters:

K - Key Type of the Map

V - Value Type of the Map

Parameters:

backingMap - Actual map being used.

loader - Loader to use

Returns:

Map

newAutoMap

public static <K,V> java.util.Map<K,V> newAutoMap(java.util.Map<K,V> backingMap,
                                                  java.lang.Class<? extends K> keyClass,
                                                  java.lang.Class<? extends V> valueClass)

Creates a LoadingMap with an auto instantiating loader. Will auto construct class of of Value when not found Since this uses Reflection, It is more effecient to define your own static loader than using this helper, but if performance is not critical, this is easier.

Type Parameters:

K - Key Type of the Map

V - Value Type of the Map

Parameters:

backingMap - Actual map being used.

keyClass - Class used for the K generic

valueClass - Class used for the V generic

Returns:

Map that auto instantiates on .get()

newAutoMap

public static <K,V> java.util.Map<K,V> newAutoMap(java.util.Map<K,V> backingMap,
                                                  java.lang.Class<? extends V> valueClass)

Creates a LoadingMap with an auto instantiating loader. Will auto construct class of of Value when not found Since this uses Reflection, It is more effecient to define your own static loader than using this helper, but if performance is not critical, this is easier.

Type Parameters:

K - Key Type of the Map

V - Value Type of the Map

Parameters:

backingMap - Actual map being used.

valueClass - Class used for the V generic

Returns:

Map that auto instantiates on .get()

newHashAutoMap

public static <K,V> java.util.Map<K,V> newHashAutoMap(java.lang.Class<? extends K> keyClass,
                                                      java.lang.Class<? extends V> valueClass)

Type Parameters:

K - Key Type of the Map

V - Value Type of the Map

Parameters:

keyClass - Class used for the K generic

valueClass - Class used for the V generic

Returns:

Map that auto instantiates on .get()

See Also:

new Auto initializing map using a HashMap.

newHashAutoMap

public static <K,V> java.util.Map<K,V> newHashAutoMap(java.lang.Class<? extends V> valueClass)

Type Parameters:

K - Key Type of the Map

V - Value Type of the Map

Parameters:

valueClass - Class used for the V generic

Returns:

Map that auto instantiates on .get()

See Also:

new Auto initializing map using a HashMap.

newHashAutoMap

public static <K,V> java.util.Map<K,V> newHashAutoMap(java.lang.Class<? extends K> keyClass,
                                                      java.lang.Class<? extends V> valueClass,
                                                      int initialCapacity,
                                                      float loadFactor)

Type Parameters:

K - Key Type of the Map

V - Value Type of the Map

Parameters:

keyClass - Class used for the K generic

valueClass - Class used for the V generic

initialCapacity - Initial capacity to use

loadFactor - Load factor to use

Returns:

Map that auto instantiates on .get()

See Also:

new Auto initializing map using a HashMap.

newHashAutoMap

public static <K,V> java.util.Map<K,V> newHashAutoMap(java.lang.Class<? extends V> valueClass,
                                                      int initialCapacity,
                                                      float loadFactor)

Type Parameters:

K - Key Type of the Map

V - Value Type of the Map

Parameters:

valueClass - Class used for the V generic

initialCapacity - Initial capacity to use

loadFactor - Load factor to use

Returns:

Map that auto instantiates on .get()

See Also:

new Auto initializing map using a HashMap.

newHashMap

public static <K,V> java.util.Map<K,V> newHashMap(com.google.common.base.Function<K,V> loader)

Initializes an auto loading map using a HashMap

Type Parameters:

K - Key Type of the Map

V - Value Type of the Map

Parameters:

loader - Loader to use

Returns:

Map

newHashMap

public static <K,V> java.util.Map<K,V> newHashMap(com.google.common.base.Function<K,V> loader,
                                                  int initialCapacity,
                                                  float loadFactor)

Initializes an auto loading map using a HashMap

Type Parameters:

K - Key Type of the Map

V - Value Type of the Map

Parameters:

loader - Loader to use

initialCapacity - Initial capacity to use

loadFactor - Load factor to use

Returns:

Map

newIdentityHashMap

public static <K,V> java.util.Map<K,V> newIdentityHashMap(com.google.common.base.Function<K,V> loader)

Initializes an auto loading map using an Identity HashMap

Type Parameters:

K - Key Type of the Map

V - Value Type of the Map

Parameters:

loader - Loader to use

Returns:

Map

newIdentityHashMap

public static <K,V> java.util.Map<K,V> newIdentityHashMap(com.google.common.base.Function<K,V> loader,
                                                          int initialCapacity)

Initializes an auto loading map using an Identity HashMap

Type Parameters:

K - Key Type of the Map

V - Value Type of the Map

Parameters:

loader - Loader to use

initialCapacity - Initial capacity to use

Returns:

Map

size

public int size()

Specified by:

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

Overrides:

size in class java.util.AbstractMap<K,V>

isEmpty

public boolean isEmpty()

Specified by:

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

Overrides:

isEmpty in class java.util.AbstractMap<K,V>

containsKey

public boolean containsKey(java.lang.Object key)

Specified by:

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

Overrides:

containsKey in class java.util.AbstractMap<K,V>

containsValue

public boolean containsValue(java.lang.Object value)

Specified by:

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

Overrides:

containsValue in class java.util.AbstractMap<K,V>

get

public V get(java.lang.Object key)

Specified by:

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

Overrides:

get in class java.util.AbstractMap<K,V>

put

public V put(K key,
             V value)

Specified by:

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

Overrides:

put in class java.util.AbstractMap<K,V>

remove

public V remove(java.lang.Object key)

Specified by:

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

Overrides:

remove in class java.util.AbstractMap<K,V>

putAll

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

Specified by:

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

Overrides:

putAll in class java.util.AbstractMap<K,V>

clear

public void clear()

Specified by:

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

Overrides:

clear in class java.util.AbstractMap<K,V>

keySet

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

Specified by:

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

Overrides:

keySet in class java.util.AbstractMap<K,V>

values

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

Specified by:

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

Overrides:

values in class java.util.AbstractMap<K,V>

equals

public boolean equals(java.lang.Object o)

Specified by:

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

Overrides:

equals in class java.util.AbstractMap<K,V>

hashCode

public int hashCode()

Specified by:

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

Overrides:

hashCode in class java.util.AbstractMap<K,V>

entrySet

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

Specified by:

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

Specified by:

entrySet in class java.util.AbstractMap<K,V>

clone

public LoadingMap<K,V> clone()

Overrides:

clone in class java.util.AbstractMap<K,V>