将Scala选项转换为Java可选 [英] Convert Scala Option to Java Optional

问题描述

我需要将Scala Option转换为Java Optional.我设法这样写:

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();
}

但我不喜欢它.

有没有简单的方法或内置的scala转换器? 我正在寻找类似的东西:

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

Options.asJava(option);

推荐答案

我在Java中想到的最短的方法是:

The shortest way I can think of in Java is:

Optional.ofNullable(option.getOrElse(null))

@RégisJean-Gilles实际上建议如果使用Scala编写转换，则建议使用更短的时间:

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

Optional.ofNullable(option.orNull)

通过这种方式，您必须知道Scala在Scala 2.12之前尚不支持Java 8，Scala 2.12尚未正式发布.查看 docs (可能会有所变化，直到发布为止).JavaConversions中没有此类转换.

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.

这篇关于将Scala选项转换为Java可选的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！