craterdog.collections

Class Map<K,V>

java.lang.Object

craterdog.smart.SmartObject<Sequence<E>>

craterdog.collections.abstractions.Sequence<E>

craterdog.collections.abstractions.Collection<E>

craterdog.collections.abstractions.OpenCollection<E>

craterdog.collections.abstractions.SortableCollection<Association<K,V>>

craterdog.collections.Map<K,V>

Type Parameters:

K - The type of the key in the association.

V - The type of the value in the association.

All Implemented Interfaces:

craterdog.core.Composite, craterdog.core.Sequential<Association<K,V>>, java.lang.Comparable<Sequence<Association<K,V>>>, java.lang.Iterable<Association<K,V>>

Direct Known Subclasses:

Dictionary

public class Map<K,V>
extends SortableCollection<Association<K,V>>

This collection class implements a sortable collection containing key-value associations. The implementation is optimized for both inserting new associations and looking up values based on their key. The implementation also dynamically scales up and down the number of buckets as the number of associations changes over time.

Author:

Derk Norton

Constructor Summary

Constructors

Constructor and Description
Map() This constructor creates a new empty map.
Map(Collection<K> keys, Collection<V> values) This constructor creates a new map using the specified keys and values.
Map(K[] keys, V[] values) This constructor creates a new map using the specified key and value arrays.
Map(Map<K,V> elements) This constructor creates a new map using the elements provided in the specified map.
Map(java.util.Map<K,V> elements) This constructor creates a new map using the elements provided in a java map.

Method Summary

Modifier and Type	Method and Description
boolean	addElement(Association<K,V> element) This method adds a new element to the collection.
static <K,V> Map<K,V>	concatenation(Map<K,V> map1, Map<K,V> map2) This function returns a new map that contains the all the associations from both the specified maps.
boolean	containsElement(Association<K,V> element) This method determines if an element is contained in the collection.
Map<K,V>	copy()
craterdog.core.Iterator<Association<K,V>>	createIterator()
craterdog.core.Manipulator<Association<K,V>>	createManipulator() This method creates a new default manipulator for the collection.
List<Association<K,V>>	getAssociations() This method returns the list of associations between keys and values for this collection.
Association<K,V>	getElement(int index) This method returns the element at the specified index.
List<Association<K,V>>	getElements(int firstIndex, int lastIndex) This method returns a collection of the elements in the specified index range.
int	getIndex(Association<K,V> element) This method return the index of the specified element, or zero if the element is not found.
List<K>	getKeys() This method returns the list of keys for the associations in this collection.
int	getSize()
V	getValue(K key) This method returns the value associated with the specified key.
List<V>	getValues() This method returns the list of values for the associations in this collection.
static <K,V> Map<K,V>	reduction(Map<K,V> map, Set<K> keys) This function returns a new map that contains only the associations with the specified keys.
void	removeAll() This method removes all elements from the collection.
boolean	removeElement(Association<K,V> element) This method removes the specified element from the collection.
V	removeValue(K key) This method removes from this collection the value associated with a key.
void	setValue(K key, V value) This method associates in this collection a new value with a key.
java.util.LinkedHashMap<K,V>	toMap()

Methods inherited from class craterdog.collections.abstractions.SortableCollection

concatenate, shuffleElements, sortElements, sortElements, sortElements

Methods inherited from class craterdog.collections.abstractions.OpenCollection

addElements, addElements, removeElements, removeElements

Methods inherited from class craterdog.collections.abstractions.Collection

containsAll, containsAny, normalizedIndex

Methods inherited from class craterdog.collections.abstractions.Sequence

compareTo, equals, hashCode, toArray

Methods inherited from class craterdog.smart.SmartObject

addSerializableClass, addSerializableClass, addSerializableClass, createMapper, fromString, fromString, toExposedString, toString, toString, toString, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface craterdog.core.Sequential

isEmpty, iterator

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

Map

public Map()

This constructor creates a new empty map.

Map

public Map(K[] keys,
           V[] values)

This constructor creates a new map using the specified key and value arrays. The number of keys must equal the number of values or an exception is thrown.

Parameters:

keys - The array of keys that should be used to create the map.

values - The array of values that should be used to create the map.

Map

public Map(Collection<K> keys,
           Collection<V> values)

This constructor creates a new map using the specified keys and values. The number of keys must equal the number of values or an exception is thrown.

Parameters:

keys - The keys that should be used to create the map.

values - The values that should be used to create the map.

Map

public Map(Map<K,V> elements)

This constructor creates a new map using the elements provided in the specified map.

Parameters:

elements - The map containing the key-value pairs to be mapped.

Map

public Map(java.util.Map<K,V> elements)

This constructor creates a new map using the elements provided in a java map.

Parameters:

elements - The java map containing the key-value pairs to be mapped.

Method Detail

toMap

public java.util.LinkedHashMap<K,V> toMap()

copy

public Map<K,V> copy()

Overrides:

copy in class craterdog.smart.SmartObject<Sequence<Association<K,V>>>

getSize

public final int getSize()

containsElement

public final boolean containsElement(Association<K,V> element)

Description copied from class: Collection

This method determines if an element is contained in the collection.

Overrides:

containsElement in class Collection<Association<K,V>>

Parameters:

element - The element to be checked for in the collection.

Returns:

Whether or not the specified element is contained in the collection.

createIterator

public craterdog.core.Iterator<Association<K,V>> createIterator()

getElement

public final Association<K,V> getElement(int index)

Description copied from class: Collection

This method returns the element at the specified index.

Specified by:

getElement in class Collection<Association<K,V>>

Parameters:

index - The index of the element to be returned.

Returns:

The element at the specified index.

getIndex

public final int getIndex(Association<K,V> element)

Description copied from class: Collection

This method return the index of the specified element, or zero if the element is not found.

Specified by:

getIndex in class Collection<Association<K,V>>

Parameters:

element - The element to be checked for in the collection.

Returns:

The index of the element of zero if the element was not found.

getElements

public final List<Association<K,V>> getElements(int firstIndex,
                                                int lastIndex)

Description copied from class: Collection

This method returns a collection of the elements in the specified index range.

Specified by:

getElements in class Collection<Association<K,V>>

Parameters:

firstIndex - The index of the first element to be returned.

lastIndex - the index of the last element to be returned.

Returns:

A collection of elements in the specified range.

addElement

public final boolean addElement(Association<K,V> element)

Description copied from class: OpenCollection

This method adds a new element to the collection. If the collection is empty then the new element will be the first element in the collection.

Specified by:

addElement in class OpenCollection<Association<K,V>>

Parameters:

element - The new element to be added.

Returns:

Whether or not the element was actually added to the collection.

removeElement

public final boolean removeElement(Association<K,V> element)

Description copied from class: OpenCollection

This method removes the specified element from the collection. If the element is not found in the collection, no changes are made.

Specified by:

removeElement in class OpenCollection<Association<K,V>>

Parameters:

element - The element to be removed.

Returns:

Whether or not the element was found.

removeAll

public final void removeAll()

Description copied from class: Collection

This method removes all elements from the collection.

Specified by:

removeAll in class Collection<Association<K,V>>

createManipulator

public craterdog.core.Manipulator<Association<K,V>> createManipulator()

Description copied from class: SortableCollection

This method creates a new default manipulator for the collection.

Specified by:

createManipulator in class SortableCollection<Association<K,V>>

Returns:

The new manipulator.

getKeys

public final List<K> getKeys()

This method returns the list of keys for the associations in this collection.

Returns:

The keys for this collection.

getValues

public final List<V> getValues()

This method returns the list of values for the associations in this collection.

Returns:

The values for this collection.

getAssociations

public final List<Association<K,V>> getAssociations()

This method returns the list of associations between keys and values for this collection.

Returns:

A list of the key/value associations that make up this collection.

getValue

public final V getValue(K key)

This method returns the value associated with the specified key.

Parameters:

key - The key for the value to be retrieved.

Returns:

The value associated with the key.

setValue

public final void setValue(K key,
                           V value)

This method associates in this collection a new value with a key. If there is already a value associated with the specified key, the new value replaces the old value.

Parameters:

key - The key for the new value.

value - The new value to be associated with the key.

removeValue

public final V removeValue(K key)

This method removes from this collection the value associated with a key. If no value is associated with the specified key then null is returned.

Parameters:

key - The key for the value to be removed.

Returns:

The value associated with the key.

concatenation

public static <K,V> Map<K,V> concatenation(Map<K,V> map1,
                                           Map<K,V> map2)

This function returns a new map that contains the all the associations from both the specified maps.

Type Parameters:

K - The type of key contained in the maps.

V - The type of value contained in the maps.

Parameters:

map1 - The first map whose elements are to be added.

map2 - The second map whose elements are to be added.

Returns:

The resulting map.

reduction

public static <K,V> Map<K,V> reduction(Map<K,V> map,
                                       Set<K> keys)

This function returns a new map that contains only the associations with the specified keys.

Type Parameters:

K - The type of key contained in the maps.

V - The type of value contained in the maps.

Parameters:

map - The map whose elements are to be reduced.

keys - The set of keys for the associates to be saved.

Returns:

The resulting map.