Package it.unimi.dsi.fastutil.objects

Class Reference2DoubleFunctions.EmptyFunction<K>

java.lang.Object

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

it.unimi.dsi.fastutil.objects.Reference2DoubleFunctions.EmptyFunction<K>

All Implemented Interfaces:

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

Direct Known Subclasses:

Reference2DoubleMaps.EmptyMap

Enclosing class:

Reference2DoubleFunctions

public static class Reference2DoubleFunctions.EmptyFunction<K>
extends AbstractReference2DoubleFunction<K>
implements Serializable, Cloneable

An immutable class representing an empty type-specific function.

This class may be useful to implement your own in case you subclass a type-specific function.

See Also:

Serialized Form

Method Summary

Modifier and Type	Method	Description
void	clear()	Removes all associations from this function (optional operation).
Object	clone()
boolean	containsKey(Object k)	Returns true if this function contains a mapping for the specified key.
double	defaultReturnValue()	Gets the default return value.
void	defaultReturnValue(double defRetValue)	Sets the default return value (optional operation).
boolean	equals(Object o)
double	getDouble(Object k)	Returns the value to which the given key is mapped.
int	hashCode()
int	size()	Returns the intended number of keys in this function, or -1 if no such number exists.
String	toString()

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

andThen, compose

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

applyAsDouble, get, put, put, remove, removeDouble

Method Details

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)

containsKey

public boolean containsKey(Object k)

Description copied from interface: Function

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

Note that for some kind of functions (e.g., hashes) this method will always return true. This default implementation, in particular, always return true.

Specified by:

containsKey in interface Function<K,Double>

Parameters:

k - the key.

Returns:

true if this function associates a value to key.

See Also:

Map.containsKey(Object)

defaultReturnValue

public double defaultReturnValue()

Description copied from interface: Reference2DoubleFunction

Gets the default return value.

This default implementation just return the default null value of the type (null for objects, 0 for scalars, false for Booleans).

Specified by:

defaultReturnValue in interface Reference2DoubleFunction<K>

Overrides:

defaultReturnValue in class AbstractReference2DoubleFunction<K>

Returns:

the current default return value.

defaultReturnValue

public void defaultReturnValue(double defRetValue)

Description copied from interface: Reference2DoubleFunction

Sets the default return value (optional operation). This value must be returned by type-specific versions of get(), put() and remove() to denote that the map does not contain the specified key. It must be 0/false/null by default.

Specified by:

defaultReturnValue in interface Reference2DoubleFunction<K>

Overrides:

defaultReturnValue in class AbstractReference2DoubleFunction<K>

Parameters:

defRetValue - the new default return value.

See Also:

Reference2DoubleFunction.defaultReturnValue()

size

public int size()

Description copied from interface: Function

Returns the intended number of keys in this function, or -1 if no such number exists.

Most function implementations will have some knowledge of the intended number of keys in their domain. In some cases, however, this might not be possible. This default implementation, in particular, returns -1.

Specified by:

size in interface Function<K,Double>

Returns:

the intended number of keys in this function, or -1 if that number is not available.

clear

public void clear()

Description copied from interface: Function

Removes all associations from this function (optional operation).

Specified by:

clear in interface Function<K,Double>

See Also:

Map.clear()

clone

public Object clone()

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

toString

public String toString()

Overrides:

toString in class Object