Package it.unimi.dsi.fastutil.objects

Class Object2DoubleFunctions

java.lang.Object

it.unimi.dsi.fastutil.objects.Object2DoubleFunctions

public final class Object2DoubleFunctions
extends Object

A class providing static methods and objects that do useful things with type-specific functions.

See Also:

Function, Collections

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Object2DoubleFunctions.EmptyFunction<K>	An immutable class representing an empty type-specific function.
static class	Object2DoubleFunctions.PrimitiveFunction<K>	An adapter for mapping generic total functions to partial primitive functions.
static class	Object2DoubleFunctions.Singleton<K>	An immutable class representing a type-specific singleton function.
static class	Object2DoubleFunctions.SynchronizedFunction<K>	A synchronized wrapper class for functions.
static class	Object2DoubleFunctions.UnmodifiableFunction<K>	An unmodifiable wrapper class for functions.

Field Summary

Fields

Modifier and Type	Field	Description
static Object2DoubleFunctions.EmptyFunction	EMPTY_FUNCTION	An empty type-specific function (immutable).

Method Summary

Modifier and Type	Method	Description
static <K> Object2DoubleFunction<K>	primitive(Function<? super K,? extends Double> f)	Returns a (partial) type-specific function based on the given total generic function.
static <K> Object2DoubleFunction<K>	singleton(K key, double value)	Returns a type-specific immutable function containing only the specified pair.
static <K> Object2DoubleFunction<K>	singleton(K key, Double value)	Returns a type-specific immutable function containing only the specified pair.
static <K> Object2DoubleFunction<K>	synchronize(Object2DoubleFunction<K> f)	Returns a synchronized type-specific function backed by the given type-specific function.
static <K> Object2DoubleFunction<K>	synchronize(Object2DoubleFunction<K> f, Object sync)	Returns a synchronized type-specific function backed by the given type-specific function, using an assigned object to synchronize.
static <K> Object2DoubleFunction<K>	unmodifiable(Object2DoubleFunction<K> f)	Returns an unmodifiable type-specific function backed by the given type-specific function.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

EMPTY_FUNCTION

public static final Object2DoubleFunctions.EmptyFunction EMPTY_FUNCTION

An empty type-specific function (immutable). It is serializable and cloneable.

Method Detail

singleton

public static <K> Object2DoubleFunction<K> singleton(K key,
                                                     double value)

Returns a type-specific immutable function containing only the specified pair. The returned function is serializable and cloneable.

Note that albeit the returned function is immutable, its default return value may be changed.

Parameters:

key - the only key of the returned function.

value - the only value of the returned function.

Returns:

a type-specific immutable function containing just the pair <key,value>.

singleton

public static <K> Object2DoubleFunction<K> singleton(K key,
                                                     Double value)

Returns a type-specific immutable function containing only the specified pair. The returned function is serializable and cloneable.

Note that albeit the returned function is immutable, its default return value may be changed.

Parameters:

key - the only key of the returned function.

value - the only value of the returned function.

Returns:

a type-specific immutable function containing just the pair <key,value>.

synchronize

public static <K> Object2DoubleFunction<K> synchronize(Object2DoubleFunction<K> f)

Returns a synchronized type-specific function backed by the given type-specific function.

Parameters:

f - the function to be wrapped in a synchronized function.

Returns:

a synchronized view of the specified function.

See Also:

Collections.synchronizedMap(java.util.Map)

synchronize

public static <K> Object2DoubleFunction<K> synchronize(Object2DoubleFunction<K> f,
                                                       Object sync)

Returns a synchronized type-specific function backed by the given type-specific function, using an assigned object to synchronize.

Parameters:

f - the function to be wrapped in a synchronized function.

sync - an object that will be used to synchronize the access to the function.

Returns:

a synchronized view of the specified function.

See Also:

Collections.synchronizedMap(java.util.Map)

unmodifiable

public static <K> Object2DoubleFunction<K> unmodifiable(Object2DoubleFunction<K> f)

Returns an unmodifiable type-specific function backed by the given type-specific function.

Parameters:

f - the function to be wrapped in an unmodifiable function.

Returns:

an unmodifiable view of the specified function.

See Also:

Collections.unmodifiableMap(java.util.Map)

primitive

public static <K> Object2DoubleFunction<K> primitive(Function<? super K,? extends Double> f)

Returns a (partial) type-specific function based on the given total generic function.

The returned function contains all keys which are not mapped to null. If the function already is a primitive function, it is returned without changes.

Warning: If the given function is a “widened” primitive function (e.g. an Int2IntFunction given to Short2ShortFunctions), it still is wrapped into a proxy, decreasing performance.

Parameters:

f - the function to be converted to a type-specific function.

Returns:

a primitive view of the specified function.

Throws:

NullPointerException - if f is null.

Since:

8.1.0

See Also:

Object2DoubleFunctions.PrimitiveFunction