Type Parameters:

T - see ToDoubleFunction

All Superinterfaces:

Function<T,OptionalDouble>

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
```
@FunctionalInterface
public interface OptionalToDoubleFunction<T>
extends Function<T,OptionalDouble>
```
Variation of ToDoubleFunction that returns OptionalDouble instead of the raw value. OptionalToDoubleFunction is typically obtained from ExceptionHandler.fromToDoubleFunction(ToDoubleFunction), in which case its return value is empty when the underlying ToDoubleFunction throws an exception. See noexception tutorial.

See Also:

ExceptionHandler.fromToDoubleFunction(ToDoubleFunction), ToDoubleFunction

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method and Description
`OptionalDouble`	`apply(T value)` Variation of `ToDoubleFunction.applyAsDouble(Object)` that returns `OptionalDouble`.
`default ToDoubleFunction<T>`	`orElse(double result)` Convert this `OptionalToDoubleFunction` to plain `ToDoubleFunction` using default value.
`default ToDoubleFunction<T>`	`orElseGet(DoubleSupplier source)` Convert this `OptionalToDoubleFunction` to plain `ToDoubleFunction` using fallback `DoubleSupplier`.

Methods inherited from interface java.util.function.Function
andThen, compose, identity

- Method Detail
  - apply
```
OptionalDouble apply(T value)
```
    Variation of ToDoubleFunction.applyAsDouble(Object) that returns OptionalDouble. If this OptionalToDoubleFunction is obtained from ExceptionHandler.fromToDoubleFunction(ToDoubleFunction), the OptionalDouble will be empty only if the underlying ToDoubleFunction throws. Otherwise the returned OptionalDouble just wraps the return value of underlying ToDoubleFunction.
    
    Specified by:
    
    apply in interface Function<T,OptionalDouble>
    
    Parameters:
    
    value - see ToDoubleFunction.applyAsDouble(Object)
    
    Returns:
    
    OptionalDouble typically wrapping return value of ToDoubleFunction.applyAsDouble(Object), or an empty OptionalDouble (typically signifying an exception)
    
    See Also:
    
    ExceptionHandler.fromToDoubleFunction(ToDoubleFunction), ToDoubleFunction.applyAsDouble(Object)
  - orElse
```
default ToDoubleFunction<T> orElse(double result)
```
    Convert this OptionalToDoubleFunction to plain ToDoubleFunction using default value. The returned ToDoubleFunction will unwrap present value from the OptionalDouble if possible, or return result if the OptionalDouble is empty.
    
    Parameters:
    
    result - default value to return instead of an empty OptionalDouble
    
    Returns:
    
    plain ToDoubleFunction that either unwraps OptionalDouble or returns default value
    
    See Also:
    
    orElseGet(DoubleSupplier), OptionalDouble.orElse(double)
  - orElseGet
```
default ToDoubleFunction<T> orElseGet(DoubleSupplier source)
```
    Convert this OptionalToDoubleFunction to plain ToDoubleFunction using fallback DoubleSupplier. The returned ToDoubleFunction will unwrap present value from the OptionalDouble if possible, or fall back to calling source if the OptionalDouble is empty.
    
    Parameters:
    
    source - DoubleSupplier to query for fallback value when OptionalDouble is empty
    
    Returns:
    
    plain ToDoubleFunction that either unwraps OptionalDouble or falls back to source
    
    See Also:
    
    orElse(double), OptionalDouble.orElseGet(DoubleSupplier)

Interface OptionalToDoubleFunction<T>

Method Summary

Methods inherited from interface java.util.function.Function

Method Detail

apply

orElse

orElseGet