play.libs

Class F.Option<T>

java.lang.Object

play.libs.F.Option<T>

All Implemented Interfaces:

java.lang.Iterable<T>, java.util.Collection<T>

Direct Known Subclasses:

F.None, F.Some

Enclosing class:

F

public abstract static class F.Option<T>
extends java.lang.Object
implements java.util.Collection<T>

Represents optional values. Instances of Option are either an instance of Some or the object None.

Constructor Summary

Constructors

Constructor and Description
Option()

Method Summary

Modifier and Type	Method and Description
boolean	add(java.lang.Object o)
boolean	addAll(java.util.Collection<? extends T> c)
void	clear()
boolean	equals(java.lang.Object obj)
abstract T	get() Returns the value if defined.
T	getOrElse(T defaultValue) Get the value if defined, otherwise return the supplied defaultValue.
int	hashCode()
abstract boolean	isDefined() Is the value of this option defined?
boolean	isEmpty()
<A> F.Option<A>	map(F.Function<T,A> function) Map this option to another value.
static <T> F.None<T>	None() Constructs a None value.
boolean	remove(java.lang.Object o)
boolean	removeAll(java.util.Collection<?> c)
boolean	retainAll(java.util.Collection<?> c)
static <T> F.Some<T>	Some(T value) Construct a Some value.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Collection

contains, containsAll, iterator, parallelStream, removeIf, size, spliterator, stream, toArray, toArray

Methods inherited from interface java.lang.Iterable

forEach

Constructor Detail

Option

public Option()

Method Detail

isDefined

public abstract boolean isDefined()

Is the value of this option defined?

Returns:

true if the value is defined, otherwise false.

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface java.util.Collection<T>

get

public abstract T get()

Returns the value if defined.

Returns:

The value if defined, otherwise null.

None

public static <T> F.None<T> None()

Constructs a None value.

Returns:

None

Some

public static <T> F.Some<T> Some(T value)

Construct a Some value.

Parameters:

value - The value to make optional

Returns:

Some T.

getOrElse

public T getOrElse(T defaultValue)

Get the value if defined, otherwise return the supplied defaultValue.

Parameters:

defaultValue - The value to return if the value of this option is not defined

Returns:

The value of this option, or defaultValue.

map

public <A> F.Option<A> map(F.Function<T,A> function)

Map this option to another value.

Parameters:

function - The function to map the option using.

Returns:

The mapped option.

Throws:

java.lang.RuntimeException - if function threw an Exception. If the exception is a RuntimeException, it will be rethrown as is, otherwise it will be wrapped in a RuntimeException.

clear

public void clear()

Specified by:

clear in interface java.util.Collection<T>

retainAll

public boolean retainAll(java.util.Collection<?> c)

Specified by:

retainAll in interface java.util.Collection<T>

add

public boolean add(java.lang.Object o)

Specified by:

add in interface java.util.Collection<T>

remove

public boolean remove(java.lang.Object o)

Specified by:

remove in interface java.util.Collection<T>

removeAll

public boolean removeAll(java.util.Collection<?> c)

Specified by:

removeAll in interface java.util.Collection<T>

addAll

public boolean addAll(java.util.Collection<? extends T> c)

Specified by:

addAll in interface java.util.Collection<T>

hashCode

public int hashCode()

Specified by:

hashCode in interface java.util.Collection<T>

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Specified by:

equals in interface java.util.Collection<T>

Overrides:

equals in class java.lang.Object