org.apache.thrift

Class Option<T>

java.lang.Object

org.apache.thrift.Option<T>

Direct Known Subclasses:

Option.None, Option.Some

public abstract class Option<T>
extends java.lang.Object

Implementation of the Option type pattern

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Option.None<T> The None type, representing an absent value (instead of "null")
static class	Option.Some<T> The Some type, representing an existence of some value

Constructor Summary

Constructors

Constructor and Description
Option()

Method Summary

Methods

Modifier and Type	Method and Description
static <T> Option<T>	fromNullable(T value) Wraps value in an Option type, depending on whether or not value is null
abstract T	get() Get the value of the Option (if it is defined)
abstract boolean	isDefined() Whether the Option is defined or not
static <T> Option.None<T>	none()
T	or(T other) Get the contained value (if defined) or else return a default value
static <T> Option.Some<T>	some(T value) Wrap value in a Some type (NB! value must not be null!)

Methods inherited from class java.lang.Object

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

Constructor Detail

Option

public Option()

Method Detail

isDefined

public abstract boolean isDefined()

Whether the Option is defined or not

Returns:

true if the Option is defined (of type Some) false if the Option is not defined (of type None)

get

public abstract T get()

Get the value of the Option (if it is defined)

Returns:

the value

Throws:

java.lang.IllegalStateException - if called on a None

or

public T or(T other)

Get the contained value (if defined) or else return a default value

Parameters:

other - what to return if the value is not defined (a None)

Returns:

either the value, or other if the value is not defined

fromNullable

public static <T> Option<T> fromNullable(T value)

Wraps value in an Option type, depending on whether or not value is null

Type Parameters:

T - type of value

Parameters:

value -

Returns:

Some(value) if value is not null, None if value is null

some

public static <T> Option.Some<T> some(T value)

Wrap value in a Some type (NB! value must not be null!)

Type Parameters:

T - type of value

Parameters:

value -

Returns:

a new Some(value)

none

public static <T> Option.None<T> none()