OptionalDouble (Lightweight-Stream-API 1.1.9 API)

java.lang.Object
- com.annimon.stream.OptionalDouble

```
public final class OptionalDouble
extends Object
```
A container object which may or may not contain a double value.

Since:

1.1.4

See Also:

Optional

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`<R> R`	`custom(Function<OptionalDouble,R> function)` Applies custom operator on `OptionalDouble`.
`static OptionalDouble`	`empty()` Returns an empty `OptionalDouble` instance.
`boolean`	`equals(Object obj)`
`OptionalDouble`	`executeIfAbsent(Runnable action)` Invokes action function if value is absent.
`OptionalDouble`	`executeIfPresent(DoubleConsumer consumer)` Invokes consumer function with the value if present.
`OptionalDouble`	`filter(DoublePredicate predicate)` Performs filtering on inner value if it is present.
`OptionalDouble`	`filterNot(DoublePredicate predicate)` Performs negated filtering on inner value if it is present.
`double`	`getAsDouble()` Returns an inner value if present, otherwise throws `NoSuchElementException`.
`int`	`hashCode()`
`void`	`ifPresent(DoubleConsumer consumer)` Invokes consumer function with value if present, otherwise does nothing.
`void`	`ifPresentOrElse(DoubleConsumer consumer, Runnable emptyAction)` If a value is present, performs the given action with the value, otherwise performs the empty-based action.
`boolean`	`isPresent()` Checks value present.
`OptionalDouble`	`map(DoubleUnaryOperator mapper)` Invokes the given mapping function on inner value if present.
`OptionalInt`	`mapToInt(DoubleToIntFunction mapper)` Invokes the given mapping function on inner value if present.
`OptionalLong`	`mapToLong(DoubleToLongFunction mapper)` Invokes the given mapping function on inner value if present.
`<U> Optional<U>`	`mapToObj(DoubleFunction<U> mapper)` Invokes the given mapping function on inner value if present.
`static OptionalDouble`	`of(double value)` Returns an `OptionalDouble` with the specified value present.
`OptionalDouble`	`or(Supplier<OptionalDouble> supplier)` Returns current `OptionalDouble` if value is present, otherwise returns an `OptionalDouble` produced by supplier function.
`double`	`orElse(double other)` Returns inner value if present, otherwise returns `other`.
`double`	`orElseGet(DoubleSupplier other)` Returns the value if present, otherwise returns value produced by supplier function.
`<X extends Throwable> double`	`orElseThrow(Supplier<X> exceptionSupplier)` Returns the value if present, otherwise throws an exception provided by supplier function.
`DoubleStream`	`stream()` Wraps a value into `DoubleStream` if present, otherwise returns an empty `DoubleStream`.
`String`	`toString()`

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Method Detail
  - empty
```
public static OptionalDouble empty()
```
    Returns an empty OptionalDouble instance.
    
    Returns:
    
    an empty OptionalDouble
  - of
```
public static OptionalDouble of(double value)
```
    Returns an OptionalDouble with the specified value present.
    
    Parameters:
    
    value - the value to be present
    
    Returns:
    
    an OptionalDouble with the value present
  - getAsDouble
```
public double getAsDouble()
```
    Returns an inner value if present, otherwise throws NoSuchElementException.
    
    Returns:
    
    the inner value of this OptionalDouble
    
    Throws:
    
    NoSuchElementException - if there is no value present
    
    See Also:
    
    isPresent()
  - isPresent
```
public boolean isPresent()
```
    Checks value present.
    
    Returns:
    
    true if a value present, false otherwise
  - ifPresent
```
public void ifPresent(DoubleConsumer consumer)
```
    Invokes consumer function with value if present, otherwise does nothing.
    
    Parameters:
    
    consumer - the consumer function to be executed if a value is present
    
    Throws:
    
    NullPointerException - if value is present and consumer is null
  - ifPresentOrElse
```
public void ifPresentOrElse(DoubleConsumer consumer,
                            Runnable emptyAction)
```
    If a value is present, performs the given action with the value, otherwise performs the empty-based action.
    
    Parameters:
    
    consumer - the consumer function to be executed, if a value is present
    
    emptyAction - the empty-based action to be performed, if no value is present
    
    Throws:
    
    NullPointerException - if a value is present and the given consumer function is null, or no value is present and the given empty-based action is null.
  - executeIfPresent
```
public OptionalDouble executeIfPresent(DoubleConsumer consumer)
```
    Invokes consumer function with the value if present. This method same as ifPresent, but does not breaks chaining
    
    Parameters:
    
    consumer - consumer function
    
    Returns:
    
    this OptionalDouble
    
    See Also:
    
    ifPresent(com.annimon.stream.function.DoubleConsumer)
  - executeIfAbsent
```
public OptionalDouble executeIfAbsent(Runnable action)
```
    Invokes action function if value is absent.
    
    Parameters:
    
    action - action that invokes if value absent
    
    Returns:
    
    this OptionalDouble
  - custom
```
public <R> R custom(Function<OptionalDouble,R> function)
```
    Applies custom operator on OptionalDouble.
    
    Type Parameters:
    
    R - the type of the result
    
    Parameters:
    
    function - a transforming function
    
    Returns:
    
    a result of the transforming function
    
    Throws:
    
    NullPointerException - if function is null
    
    Since:
    
    1.1.9
  - filter
```
public OptionalDouble filter(DoublePredicate predicate)
```
    Performs filtering on inner value if it is present.
    
    Parameters:
    
    predicate - a predicate function
    
    Returns:
    
    this OptionalDouble if the value is present and matches predicate, otherwise an empty OptionalDouble
  - filterNot
```
public OptionalDouble filterNot(DoublePredicate predicate)
```
    Performs negated filtering on inner value if it is present.
    
    Parameters:
    
    predicate - a predicate function
    
    Returns:
    
    this OptionalDouble if the value is present and doesn't matches predicate, otherwise an empty OptionalDouble
    
    Since:
    
    1.1.9
  - map
```
public OptionalDouble map(DoubleUnaryOperator mapper)
```
    Invokes the given mapping function on inner value if present.
    
    Parameters:
    
    mapper - mapping function
    
    Returns:
    
    an OptionalDouble with transformed value if present, otherwise an empty OptionalDouble
    
    Throws:
    
    NullPointerException - if value is present and mapper is null
  - mapToObj
```
public <U> Optional<U> mapToObj(DoubleFunction<U> mapper)
```
    Invokes the given mapping function on inner value if present.
    
    Type Parameters:
    
    U - the type of result value
    
    Parameters:
    
    mapper - mapping function
    
    Returns:
    
    an Optional with transformed value if present, otherwise an empty Optional
    
    Throws:
    
    NullPointerException - if value is present and mapper is null
  - mapToInt
```
public OptionalInt mapToInt(DoubleToIntFunction mapper)
```
    Invokes the given mapping function on inner value if present.
    
    Parameters:
    
    mapper - mapping function
    
    Returns:
    
    an OptionalInt with transformed value if present, otherwise an empty OptionalInt
    
    Throws:
    
    NullPointerException - if value is present and mapper is null
  - mapToLong
```
public OptionalLong mapToLong(DoubleToLongFunction mapper)
```
    Invokes the given mapping function on inner value if present.
    
    Parameters:
    
    mapper - mapping function
    
    Returns:
    
    an OptionalLong with transformed value if present, otherwise an empty OptionalLong
    
    Throws:
    
    NullPointerException - if value is present and mapper is null
  - stream
```
public DoubleStream stream()
```
    Wraps a value into DoubleStream if present, otherwise returns an empty DoubleStream.
    
    Returns:
    
    the optional value as an DoubleStream
  - or
```
public OptionalDouble or(Supplier<OptionalDouble> supplier)
```
    Returns current OptionalDouble if value is present, otherwise returns an OptionalDouble produced by supplier function.
    
    Parameters:
    
    supplier - supplier function that produces an OptionalDouble to be returned
    
    Returns:
    
    this OptionalDouble if value is present, otherwise an OptionalDouble produced by supplier function
    
    Throws:
    
    NullPointerException - if value is not present and supplier or value produced by it is null
  - orElse
```
public double orElse(double other)
```
    Returns inner value if present, otherwise returns other.
    
    Parameters:
    
    other - the value to be returned if there is no value present
    
    Returns:
    
    the value, if present, otherwise other
  - orElseGet
```
public double orElseGet(DoubleSupplier other)
```
    Returns the value if present, otherwise returns value produced by supplier function.
    
    Parameters:
    
    other - supplier function that produces value if inner value is not present
    
    Returns:
    
    the value if present otherwise the result of other.getAsDouble()
    
    Throws:
    
    NullPointerException - if value is not present and other is null
  - orElseThrow
```
public <X extends Throwable> double orElseThrow(Supplier<X> exceptionSupplier)
                                         throws X extends Throwable
```
    Returns the value if present, otherwise throws an exception provided by supplier function.
    
    Type Parameters:
    
    X - the type of exception to be thrown
    
    Parameters:
    
    exceptionSupplier - supplier function that produces an exception to be thrown
    
    Returns:
    
    inner value if present
    
    Throws:
    
    X - if inner value is not present
    
    X extends Throwable
  - equals
```
public boolean equals(Object obj)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object

Class OptionalDouble

Method Summary

Methods inherited from class java.lang.Object

Method Detail

empty

of

getAsDouble

isPresent

ifPresent

ifPresentOrElse

executeIfPresent

executeIfAbsent

custom

filter

filterNot

map

mapToObj

mapToInt

mapToLong

stream

or

orElse

orElseGet

orElseThrow

equals

hashCode

toString