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:

Map<K,V>

public class LoadingMap<K,V>
extends 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

AbstractMap.SimpleEntry<K extends Object,V extends Object>, AbstractMap.SimpleImmutableEntry<K extends Object,V extends Object>

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

Map.Entry<K extends Object,V extends Object>

Constructor Summary

Constructors

Constructor	Description
LoadingMap(Map<K,V> backingMap, 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(Object key)
boolean	containsValue(Object value)
Set<Map.Entry<K,V>>	entrySet()
boolean	equals(Object o)
V	get(Object key)
int	hashCode()
boolean	isEmpty()
Set<K>	keySet()
static <K,V> Map<K,V>	newAutoMap(Map<K,V> backingMap, Class<? extends K> keyClass, Class<? extends V> valueClass)	Creates a LoadingMap with an auto instantiating loader.
static <K,V> Map<K,V>	newAutoMap(Map<K,V> backingMap, Class<? extends V> valueClass)	Creates a LoadingMap with an auto instantiating loader.
static <K,V> Map<K,V>	newHashAutoMap(Class<? extends K> keyClass, Class<? extends V> valueClass)
static <K,V> Map<K,V>	newHashAutoMap(Class<? extends K> keyClass, Class<? extends V> valueClass, int initialCapacity, float loadFactor)
static <K,V> Map<K,V>	newHashAutoMap(Class<? extends V> valueClass)
static <K,V> Map<K,V>	newHashAutoMap(Class<? extends V> valueClass, int initialCapacity, float loadFactor)
static <K,V> Map<K,V>	newHashMap(Function<K,V> loader)	Initializes an auto loading map using a HashMap
static <K,V> Map<K,V>	newHashMap(Function<K,V> loader, int initialCapacity)	Initializes an auto loading map using a HashMap
static <K,V> Map<K,V>	newHashMap(Function<K,V> loader, int initialCapacity, float loadFactor)	Initializes an auto loading map using a HashMap
static <K,V> Map<K,V>	newIdentityHashMap(Function<K,V> loader)	Initializes an auto loading map using an Identity HashMap
static <K,V> Map<K,V>	newIdentityHashMap(Function<K,V> loader, int initialCapacity)	Initializes an auto loading map using an Identity HashMap
static <K,V> Map<K,V>	of(Map<K,V> backingMap, Function<K,V> loader)	Creates a new LoadingMap with the specified map and loader
V	put(K key, V value)
void	putAll(Map<? extends K,? extends V> m)
V	remove(Object key)
int	size()
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(@NotNull
                  Map<K,V> backingMap,
                  @NotNull
                  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

@NotNull
public static <K,V> Map<K,V> of(@NotNull
                                Map<K,V> backingMap,
                                @NotNull
                                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

@NotNull
public static <K,V> Map<K,V> newAutoMap(@NotNull
                                        Map<K,V> backingMap,
                                        @Nullable
                                        Class<? extends K> keyClass,
                                        @NotNull
                                        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

@NotNull
public static <K,V> Map<K,V> newAutoMap(@NotNull
                                        Map<K,V> backingMap,
                                        @NotNull
                                        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

@NotNull
public static <K,V> Map<K,V> newHashAutoMap(@Nullable
                                            Class<? extends K> keyClass,
                                            @NotNull
                                            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

@NotNull
public static <K,V> Map<K,V> newHashAutoMap(@NotNull
                                            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

@NotNull
public static <K,V> Map<K,V> newHashAutoMap(@Nullable
                                            Class<? extends K> keyClass,
                                            @NotNull
                                            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

@NotNull
public static <K,V> Map<K,V> newHashAutoMap(@NotNull
                                            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

@NotNull
public static <K,V> Map<K,V> newHashMap(@NotNull
                                        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

@NotNull
public static <K,V> Map<K,V> newHashMap(@NotNull
                                        Function<K,V> loader,
                                        int initialCapacity)

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

Returns:

Map

newHashMap

@NotNull
public static <K,V> Map<K,V> newHashMap(@NotNull
                                        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

@NotNull
public static <K,V> Map<K,V> newIdentityHashMap(@NotNull
                                                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

@NotNull
public static <K,V> Map<K,V> newIdentityHashMap(@NotNull
                                                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 Map<K,V>

Overrides:

size in class AbstractMap<K,V>

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Map<K,V>

Overrides:

isEmpty in class AbstractMap<K,V>

containsKey

public boolean containsKey(@Nullable
                           Object key)

Specified by:

containsKey in interface Map<K,V>

Overrides:

containsKey in class AbstractMap<K,V>

containsValue

public boolean containsValue(@Nullable
                             Object value)

Specified by:

containsValue in interface Map<K,V>

Overrides:

containsValue in class AbstractMap<K,V>

get

@Nullable
public V get(@Nullable
             Object key)

Specified by:

get in interface Map<K,V>

Overrides:

get in class AbstractMap<K,V>

put

@Nullable
public V put(@Nullable
             K key,
             @Nullable
             V value)

Specified by:

put in interface Map<K,V>

Overrides:

put in class AbstractMap<K,V>

remove

@Nullable
public V remove(@Nullable
                Object key)

Specified by:

remove in interface Map<K,V>

Overrides:

remove in class AbstractMap<K,V>

putAll

public void putAll(@NotNull
                   Map<? extends K,? extends V> m)

Specified by:

putAll in interface Map<K,V>

Overrides:

putAll in class AbstractMap<K,V>

clear

public void clear()

Specified by:

clear in interface Map<K,V>

Overrides:

clear in class AbstractMap<K,V>

keySet

@NotNull
public Set<K> keySet()

Specified by:

keySet in interface Map<K,V>

Overrides:

keySet in class AbstractMap<K,V>

values

@NotNull
public Collection<V> values()

Specified by:

values in interface Map<K,V>

Overrides:

values in class AbstractMap<K,V>

equals

public boolean equals(@Nullable
                      Object o)

Specified by:

equals in interface Map<K,V>

Overrides:

equals in class AbstractMap<K,V>

hashCode

public int hashCode()

Specified by:

hashCode in interface Map<K,V>

Overrides:

hashCode in class AbstractMap<K,V>

entrySet

@NotNull
public Set<Map.Entry<K,V>> entrySet()

Specified by:

entrySet in interface Map<K,V>

Specified by:

entrySet in class AbstractMap<K,V>

clone

@NotNull
public LoadingMap<K,V> clone()

Overrides:

clone in class AbstractMap<K,V>