Package it.unimi.dsi.fastutil.objects

Class Reference2DoubleArrayMap<K>

java.lang.Object

it.unimi.dsi.fastutil.objects.AbstractReference2DoubleFunction<K>

it.unimi.dsi.fastutil.objects.AbstractReference2DoubleMap<K>

it.unimi.dsi.fastutil.objects.Reference2DoubleArrayMap<K>

All Implemented Interfaces:

Function<K,Double>, Reference2DoubleFunction<K>, Reference2DoubleMap<K>, Serializable, Cloneable, Function<K,Double>, ToDoubleFunction<K>, Map<K,Double>

public class Reference2DoubleArrayMap<K>
extends AbstractReference2DoubleMap<K>
implements Serializable, Cloneable

A simple, brute-force implementation of a map based on two parallel backing arrays.

The main purpose of this implementation is that of wrapping cleanly the brute-force approach to the storage of a very small number of pairs: just put them into two parallel arrays and scan linearly to find an item.

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class it.unimi.dsi.fastutil.objects.AbstractReference2DoubleMap

AbstractReference2DoubleMap.BasicEntry<K>, AbstractReference2DoubleMap.BasicEntrySet<K>

Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.objects.Reference2DoubleMap

Reference2DoubleMap.Entry<K>, Reference2DoubleMap.FastEntrySet<K>

Constructor Summary

Constructors

Constructor	Description
Reference2DoubleArrayMap()	Creates a new empty array map.
Reference2DoubleArrayMap(int capacity)	Creates a new empty array map of given capacity.
Reference2DoubleArrayMap(Reference2DoubleMap<K> m)	Creates a new empty array map copying the entries of a given map.
Reference2DoubleArrayMap(Object[] key, double[] value)	Creates a new empty array map with given key and value backing arrays.
Reference2DoubleArrayMap(Object[] key, double[] value, int size)	Creates a new array map with given key and value backing arrays, using the given number of elements.
Reference2DoubleArrayMap(Map<? extends K,? extends Double> m)	Creates a new empty array map copying the entries of a given map.

Method Summary

Modifier and Type	Method	Description
void	clear()	Removes all of the mappings from this map (optional operation).
Reference2DoubleArrayMap<K>	clone()	Returns a deep copy of this map.
boolean	containsKey(Object k)	Returns true if this function contains a mapping for the specified key.
boolean	containsValue(double v)	Returns true if this map maps one or more keys to the specified value.
double	getDouble(Object k)	Returns the value to which the given key is mapped.
boolean	isEmpty()
ReferenceSet<K>	keySet()	Returns a type-specific-set view of the keys of this map.
double	put(K k, double v)	Adds a pair to the map (optional operation).
Reference2DoubleMap.FastEntrySet<K>	reference2DoubleEntrySet()	Returns a type-specific set view of the mappings contained in this map.
double	removeDouble(Object k)	Removes the mapping with the given key (optional operation).
int	size()	Returns the number of key/value mappings in this map.
DoubleCollection	values()	Returns a type-specific-set view of the values of this map.

Methods inherited from class it.unimi.dsi.fastutil.objects.AbstractReference2DoubleMap

equals, hashCode, mergeDouble, putAll, toString

Methods inherited from class it.unimi.dsi.fastutil.objects.AbstractReference2DoubleFunction

defaultReturnValue, defaultReturnValue

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface it.unimi.dsi.fastutil.Function

apply

Methods inherited from interface java.util.function.Function

compose

Methods inherited from interface java.util.Map

compute, computeIfAbsent, computeIfPresent, replaceAll

Methods inherited from interface it.unimi.dsi.fastutil.objects.Reference2DoubleFunction

andThen, andThenByte, andThenChar, andThenDouble, andThenFloat, andThenInt, andThenLong, andThenObject, andThenReference, andThenShort, applyAsDouble, composeByte, composeChar, composeDouble, composeFloat, composeInt, composeLong, composeObject, composeReference, composeShort

Methods inherited from interface it.unimi.dsi.fastutil.objects.Reference2DoubleMap

computeDouble, computeDoubleIfAbsent, computeDoubleIfAbsentPartial, computeDoubleIfPresent, computeIfAbsent, computeIfAbsent, containsValue, defaultReturnValue, defaultReturnValue, entrySet, forEach, get, getOrDefault, getOrDefault, merge, merge, mergeDouble, mergeDouble, put, putIfAbsent, putIfAbsent, remove, remove, remove, replace, replace, replace, replace

Constructor Details

Reference2DoubleArrayMap

public Reference2DoubleArrayMap(Object[] key,
 double[] value)

Creates a new empty array map with given key and value backing arrays. The resulting map will have as many entries as the given arrays.

It is responsibility of the caller that the elements of key are distinct.

Parameters:

key - the key array.

value - the value array (it must have the same length as key).

Reference2DoubleArrayMap

public Reference2DoubleArrayMap()

Creates a new empty array map.

Reference2DoubleArrayMap

public Reference2DoubleArrayMap(int capacity)

Creates a new empty array map of given capacity.

Parameters:

capacity - the initial capacity.

Reference2DoubleArrayMap

public Reference2DoubleArrayMap(Reference2DoubleMap<K> m)

Creates a new empty array map copying the entries of a given map.

Parameters:

m - a map.

Reference2DoubleArrayMap

public Reference2DoubleArrayMap(Map<? extends K,? extends Double> m)

Creates a new empty array map copying the entries of a given map.

Parameters:

m - a map.

Reference2DoubleArrayMap

public Reference2DoubleArrayMap(Object[] key,
 double[] value,
 int size)

Creates a new array map with given key and value backing arrays, using the given number of elements.

It is responsibility of the caller that the first size elements of key are distinct.

Parameters:

key - the key array.

value - the value array (it must have the same length as key).

size - the number of valid elements in key and value.

Method Details

reference2DoubleEntrySet

public Reference2DoubleMap.FastEntrySet<K> reference2DoubleEntrySet()

Description copied from interface: Reference2DoubleMap

Returns a type-specific set view of the mappings contained in this map.

This method is necessary because there is no inheritance along type parameters: it is thus impossible to strengthen Map.entrySet() so that it returns an ObjectSet of type-specific entries (the latter makes it possible to access keys and values with type-specific methods).

Specified by:

reference2DoubleEntrySet in interface Reference2DoubleMap<K>

Returns:

a type-specific set view of the mappings contained in this map.

See Also:

• Map.entrySet()

getDouble

public double getDouble(Object k)

Description copied from interface: Reference2DoubleFunction

Returns the value to which the given key is mapped.

Specified by:

getDouble in interface Reference2DoubleFunction<K>

Parameters:

k - the key.

Returns:

the corresponding value, or the default return value if no value was present for the given key.

See Also:

• Function.get(Object)

size

public int size()

Description copied from interface: Reference2DoubleMap

Returns the number of key/value mappings in this map. If the map contains more than Integer.MAX_VALUE elements, returns Integer.MAX_VALUE.

Specified by:

size in interface Function<K,Double>

Specified by:

size in interface Map<K,Double>

Specified by:

size in interface Reference2DoubleMap<K>

Returns:

the number of key-value mappings in this map.

See Also:

• Size64

clear

public void clear()

Description copied from interface: Reference2DoubleMap

Removes all of the mappings from this map (optional operation). The map will be empty after this call returns.

Specified by:

clear in interface Function<K,Double>

Specified by:

clear in interface Map<K,Double>

Specified by:

clear in interface Reference2DoubleMap<K>

See Also:

• Map.clear()

containsKey

public boolean containsKey(Object k)

Description copied from class: AbstractReference2DoubleMap

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

Specified by:

containsKey in interface Function<K,Double>

Specified by:

containsKey in interface Map<K,Double>

Specified by:

containsKey in interface Reference2DoubleMap<K>

Overrides:

containsKey in class AbstractReference2DoubleMap<K>

Parameters:

k - the key.

Returns:

true if this function associates a value to key.

See Also:

• Map.containsKey(Object)

containsValue

public boolean containsValue(double v)

Description copied from class: AbstractReference2DoubleMap

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

Specified by:

containsValue in interface Reference2DoubleMap<K>

Overrides:

containsValue in class AbstractReference2DoubleMap<K>

See Also:

• Map.containsValue(Object)

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Map<K,Double>

Overrides:

isEmpty in class AbstractReference2DoubleMap<K>

put

public double put(K k,
 double v)

Description copied from interface: Reference2DoubleFunction

Adds a pair to the map (optional operation).

Specified by:

put in interface Reference2DoubleFunction<K>

Parameters:

k - the key.

v - the value.

Returns:

the old value, or the default return value if no value was present for the given key.

See Also:

• Function.put(Object,Object)

removeDouble

public double removeDouble(Object k)

Description copied from interface: Reference2DoubleFunction

Removes the mapping with the given key (optional operation).

Specified by:

removeDouble in interface Reference2DoubleFunction<K>

Parameters:

k - the key.

Returns:

the old value, or the default return value if no value was present for the given key.

See Also:

• Function.remove(Object)

keySet

public ReferenceSet<K> keySet()

Description copied from class: AbstractReference2DoubleMap

Returns a type-specific-set view of the keys of this map.

The view is backed by the set returned by Map.entrySet(). Note that no attempt is made at caching the result of this method, as this would require adding some attributes that lightweight implementations would not need. Subclasses may easily override this policy by calling this method and caching the result, but implementors are encouraged to write more efficient ad-hoc implementations.

Specified by:

keySet in interface Map<K,Double>

Specified by:

keySet in interface Reference2DoubleMap<K>

Overrides:

keySet in class AbstractReference2DoubleMap<K>

Returns:

a set view of the keys of this map; it may be safely cast to a type-specific interface.

See Also:

• Map.keySet()

values

public DoubleCollection values()

Description copied from class: AbstractReference2DoubleMap

Returns a type-specific-set view of the values of this map.

The view is backed by the set returned by Map.entrySet(). Note that no attempt is made at caching the result of this method, as this would require adding some attributes that lightweight implementations would not need. Subclasses may easily override this policy by calling this method and caching the result, but implementors are encouraged to write more efficient ad-hoc implementations.

Specified by:

values in interface Map<K,Double>

Specified by:

values in interface Reference2DoubleMap<K>

Overrides:

values in class AbstractReference2DoubleMap<K>

Returns:

a set view of the values of this map; it may be safely cast to a type-specific interface.

See Also:

• Map.values()

clone

public Reference2DoubleArrayMap<K> clone()

Returns a deep copy of this map.

This method performs a deep copy of this hash map; the data stored in the map, however, is not cloned. Note that this makes a difference only for object keys.

Returns:

a deep copy of this map.