Package it.unimi.dsi.fastutil.objects

Class Object2LongArrayMap<K>

java.lang.Object

it.unimi.dsi.fastutil.objects.AbstractObject2LongFunction<K>

it.unimi.dsi.fastutil.objects.AbstractObject2LongMap<K>

it.unimi.dsi.fastutil.objects.Object2LongArrayMap<K>

All Implemented Interfaces:

Function<K,Long>, Object2LongFunction<K>, Object2LongMap<K>, Serializable, Cloneable, Function<K,Long>, ToLongFunction<K>, Map<K,Long>

public class Object2LongArrayMap<K>
extends AbstractObject2LongMap<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.AbstractObject2LongMap

AbstractObject2LongMap.BasicEntry<K>, AbstractObject2LongMap.BasicEntrySet<K>

Nested classes/interfaces inherited from interface it.unimi.dsi.fastutil.objects.Object2LongMap

Object2LongMap.Entry<K>, Object2LongMap.FastEntrySet<K>

Constructor Summary

Constructors

Constructor	Description
Object2LongArrayMap()	Creates a new empty array map.
Object2LongArrayMap(int capacity)	Creates a new empty array map of given capacity.
Object2LongArrayMap(Object2LongMap<K> m)	Creates a new empty array map copying the entries of a given map.
Object2LongArrayMap(Object[] key, long[] value)	Creates a new empty array map with given key and value backing arrays.
Object2LongArrayMap(Object[] key, long[] value, int size)	Creates a new array map with given key and value backing arrays, using the given number of elements.
Object2LongArrayMap(Map<? extends K,? extends Long> 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).
Object2LongArrayMap<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(long v)	Returns true if this map maps one or more keys to the specified value.
long	getLong(Object k)	Returns the value to which the given key is mapped.
boolean	isEmpty()
ObjectSet<K>	keySet()	Returns a type-specific-set view of the keys of this map.
Object2LongMap.FastEntrySet<K>	object2LongEntrySet()	Returns a type-specific set view of the mappings contained in this map.
long	put(K k, long v)	Adds a pair to the map (optional operation).
long	removeLong(Object k)	Removes the mapping with the given key (optional operation).
int	size()	Returns the number of key/value mappings in this map.
LongCollection	values()	Returns a type-specific-set view of the values of this map.

Methods inherited from class it.unimi.dsi.fastutil.objects.AbstractObject2LongMap

equals, hashCode, mergeLong, putAll, toString

Methods inherited from class it.unimi.dsi.fastutil.objects.AbstractObject2LongFunction

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.Object2LongFunction

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

Methods inherited from interface it.unimi.dsi.fastutil.objects.Object2LongMap

computeIfAbsent, computeIfAbsent, computeLong, computeLongIfAbsent, computeLongIfAbsentPartial, computeLongIfPresent, containsValue, defaultReturnValue, defaultReturnValue, entrySet, forEach, get, getOrDefault, getOrDefault, merge, merge, mergeLong, mergeLong, put, putIfAbsent, putIfAbsent, remove, remove, remove, replace, replace, replace, replace

Constructor Details

Object2LongArrayMap

public Object2LongArrayMap(Object[] key,
 long[] 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).

Object2LongArrayMap

public Object2LongArrayMap()

Creates a new empty array map.

Object2LongArrayMap

public Object2LongArrayMap(int capacity)

Creates a new empty array map of given capacity.

Parameters:

capacity - the initial capacity.

Object2LongArrayMap

public Object2LongArrayMap(Object2LongMap<K> m)

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

Parameters:

m - a map.

Object2LongArrayMap

public Object2LongArrayMap(Map<? extends K,? extends Long> m)

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

Parameters:

m - a map.

Object2LongArrayMap

public Object2LongArrayMap(Object[] key,
 long[] 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

object2LongEntrySet

public Object2LongMap.FastEntrySet<K> object2LongEntrySet()

Description copied from interface: Object2LongMap

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:

object2LongEntrySet in interface Object2LongMap<K>

Returns:

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

See Also:

• Map.entrySet()

getLong

public long getLong(Object k)

Description copied from interface: Object2LongFunction

Returns the value to which the given key is mapped.

Specified by:

getLong in interface Object2LongFunction<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: Object2LongMap

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,Long>

Specified by:

size in interface Map<K,Long>

Specified by:

size in interface Object2LongMap<K>

Returns:

the number of key-value mappings in this map.

See Also:

• Size64

clear

public void clear()

Description copied from interface: Object2LongMap

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,Long>

Specified by:

clear in interface Map<K,Long>

Specified by:

clear in interface Object2LongMap<K>

See Also:

• Map.clear()

containsKey

public boolean containsKey(Object k)

Description copied from class: AbstractObject2LongMap

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

Specified by:

containsKey in interface Function<K,Long>

Specified by:

containsKey in interface Map<K,Long>

Specified by:

containsKey in interface Object2LongMap<K>

Overrides:

containsKey in class AbstractObject2LongMap<K>

Parameters:

k - the key.

Returns:

true if this function associates a value to key.

See Also:

• Map.containsKey(Object)

containsValue

public boolean containsValue(long v)

Description copied from class: AbstractObject2LongMap

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

Specified by:

containsValue in interface Object2LongMap<K>

Overrides:

containsValue in class AbstractObject2LongMap<K>

See Also:

• Map.containsValue(Object)

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Map<K,Long>

Overrides:

isEmpty in class AbstractObject2LongMap<K>

put

public long put(K k,
 long v)

Description copied from interface: Object2LongFunction

Adds a pair to the map (optional operation).

Specified by:

put in interface Object2LongFunction<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)

removeLong

public long removeLong(Object k)

Description copied from interface: Object2LongFunction

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

Specified by:

removeLong in interface Object2LongFunction<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 ObjectSet<K> keySet()

Description copied from class: AbstractObject2LongMap

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,Long>

Specified by:

keySet in interface Object2LongMap<K>

Overrides:

keySet in class AbstractObject2LongMap<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 LongCollection values()

Description copied from class: AbstractObject2LongMap

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,Long>

Specified by:

values in interface Object2LongMap<K>

Overrides:

values in class AbstractObject2LongMap<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 Object2LongArrayMap<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.