Package org.forgerock.util

Class LazyMap<K,V>

java.lang.Object

org.forgerock.util.LazyMap<K,V>

Type Parameters:

K - The type of key.

V - The type of value.

All Implemented Interfaces:

Map<K,V>

public class LazyMap<K,V>
extends Object
implements Map<K,V>

A map with lazy initialization. The factory is called to initialize the map on the first call to one of this object's methods.

Nested Class Summary

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

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

Field Summary

Fields

Modifier and Type	Field	Description
protected Factory<Map<K,V>>	factory	Factory to create the instance of the map to expose.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	LazyMap()	Constructs a new lazy map.
	LazyMap(Factory<Map<K,V>> factory)	Constructs a new lazy map.

Method Summary

Modifier and Type	Method	Description
void	clear()	Removes all of the mappings from the map.
boolean	containsKey(Object key)	Returns true if this map contains a mapping for the specified key.
boolean	containsValue(Object value)	Returns true if the map maps one or more keys to the specified value.
Set<Map.Entry<K,V>>	entrySet()	Returns a Set view of the mappings contained in the map.
boolean	equals(Object o)	Compares the specified object with the map for equality.
V	get(Object key)	Returns the value to which the specified key is mapped, or null if the map contains no mapping for the key.
int	hashCode()	Returns the hash code value for the map.
boolean	isEmpty()	Returns true if the map contains no key-value mappings.
Set<K>	keySet()	Returns a Set view of the keys contained in the map.
V	put(K key, V value)	Associates the specified value with the specified key in the map.
void	putAll(Map<? extends K,? extends V> m)	Copies all of the mappings from the specified map to the map.
V	remove(Object key)	Removes the mapping for a key from the map if it is present.
int	size()	Returns the number of key-value mappings in this map.
Collection<V>	values()	Returns a Collection view of the values contained in the map.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Map

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

Field Detail

factory

protected Factory<Map<K,V>> factory

Factory to create the instance of the map to expose.

Constructor Detail

LazyMap

protected LazyMap()

Constructs a new lazy map. Allows factory to be set in subclass constructor.

LazyMap

public LazyMap(Factory<Map<K,V>> factory)

Constructs a new lazy map.

Parameters:

factory - factory to create the map instance to expose.

Method Detail

size

public int size()

Returns the number of key-value mappings in this map.

Specified by:

size in interface Map<K,V>

isEmpty

public boolean isEmpty()

Returns true if the map contains no key-value mappings.

Specified by:

isEmpty in interface Map<K,V>

containsKey

public boolean containsKey(Object key)

Returns true if this map contains a mapping for the specified key.

Specified by:

containsKey in interface Map<K,V>

Parameters:

key - the key whose presence in this map is to be tested.

Returns:

true if this map contains a mapping for the specified key.

containsValue

public boolean containsValue(Object value)

Returns true if the map maps one or more keys to the specified value.

Specified by:

containsValue in interface Map<K,V>

Parameters:

value - the value whose presence in the map is to be tested.

Returns:

true if the map maps one or more keys to the specified value.

get

public V get(Object key)

Returns the value to which the specified key is mapped, or null if the map contains no mapping for the key.

Specified by:

get in interface Map<K,V>

Parameters:

key - the key whose associated value is to be returned.

Returns:

the value to which the specified key is mapped, or null if no mapping.

put

public V put(K key,
             V value)

Associates the specified value with the specified key in the map.

Specified by:

put in interface Map<K,V>

Parameters:

key - key with which the specified value is to be associated.

value - value to be associated with the specified key.

Returns:

the previous value associated with key, or null if no mapping.

remove

public V remove(Object key)

Removes the mapping for a key from the map if it is present.

Specified by:

remove in interface Map<K,V>

Parameters:

key - key whose mapping is to be removed from the map.

Returns:

the previous value associated with key, or null if no mapping.

putAll

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

Copies all of the mappings from the specified map to the map.

Specified by:

putAll in interface Map<K,V>

Parameters:

m - mappings to be stored in the map.

clear

public void clear()

Removes all of the mappings from the map.

Specified by:

clear in interface Map<K,V>

keySet

public Set<K> keySet()

Returns a Set view of the keys contained in the map.

Specified by:

keySet in interface Map<K,V>

values

public Collection<V> values()

Returns a Collection view of the values contained in the map.

Specified by:

values in interface Map<K,V>

entrySet

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

Returns a Set view of the mappings contained in the map.

Specified by:

entrySet in interface Map<K,V>

hashCode

public int hashCode()

Returns the hash code value for the map.

Specified by:

hashCode in interface Map<K,V>

Overrides:

hashCode in class Object

equals

public boolean equals(Object o)

Compares the specified object with the map for equality.

Specified by:

equals in interface Map<K,V>

Overrides:

equals in class Object

Parameters:

o - object to be compared for equality with the map.

Returns:

true if the specified object is equal to the map.