org.dmfs.optional

Class Absent<T>

java.lang.Object

org.dmfs.optional.Absent<T>

All Implemented Interfaces:

Optional<T>

public final class Absent<T>
extends java.lang.Object
implements Optional<T>

An Optional value that's never present.

Constructor Summary

Constructors

Constructor and Description
Absent()

Method Summary

Modifier and Type	Method and Description
static <T> Absent<T>	absent() Returns an Absent value.
boolean	isPresent() Returns whether the optional value is present.
T	value() Returns the optional value.
T	value(T defaultValue) Returns the optional value or the given default value if the optional value is not present.

Methods inherited from class java.lang.Object

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

Constructor Detail

Absent

public Absent()

Method Detail

absent

public static <T> Absent<T> absent()

Returns an Absent value.

Type Parameters:

T - The type of the absent value.

Returns:

An Absent of the given type.

isPresent

public boolean isPresent()

Description copied from interface: Optional

Returns whether the optional value is present.

Specified by:

isPresent in interface Optional<T>

Returns:

true if the value is present, false otherwise.

value

public T value(T defaultValue)

Description copied from interface: Optional

Returns the optional value or the given default value if the optional value is not present.

Specified by:

value in interface Optional<T>

Parameters:

defaultValue - The value to return if the optional value is not present.

Returns:

The optional value or the default value.

value

public T value()
        throws java.util.NoSuchElementException

Description copied from interface: Optional

Returns the optional value.

Specified by:

value in interface Optional<T>

Returns:

The value.

Throws:

java.util.NoSuchElementException - if the optional value is not present.