Convert Scala Option to Java Optional

Question

I need to convert Scala Option to Java Optional. I managed to wrote this:

public <T> Optional<T> convertOption2Optional(Option<T> option) {
    return option.isDefined() ? Optional.of(option.get()) : Optional.empty();
}

But I don't like it.

Is there a simple way to do it, or a built-in scala converter? I'm looking for something like:

Options.asJava(option);

Answer 1

The shortest way I can think of in Java is:

Optional.ofNullable(option.getOrElse(null))

@RégisJean-Gilles actually suggested even shorter if you are writing the conversion in Scala:

Optional.ofNullable(option.orNull)

By the way you must know that Scala does not support Java 8 until Scala 2.12, which is not officially out yet. Looking at the docs (which may change until the release) there is no such conversion in JavaConversions.

Answer 2

Starting Scala 2.13, there is a dedicated converter from scala's Option to java's Optional.

From Java (the explicit way):

import scala.jdk.javaapi.OptionConverters;

// val option: Option[Int] = Some(42)
OptionConverters.toJava(option);
// java.util.Optional[Int] = Optional[42]

From Scala (the implicit way):

import scala.jdk.OptionConverters._

// val option: Option[Int] = Some(42)
option.toJava
// java.util.Optional[Int] = Optional[42]