returning method in Java with Option in Scala?
Suppose I have a method session.get(str: String): String
but you don't know whether it will return you a string or a null, because it comes from Java.
Is there an easier way to treat this in Scala instead of session.get("foo") == null
? Maybe some magic apply like ToOption(session.get("foo"))
and then I can treat it in Scala way like
ToOption(session.get("foo")) match {
case Some(_) =>;
case None =>;
}
Option
伴侣对象的apply
方法充当可空引用的转换函数:
scala> Option(null)
res4: Option[Null] = None
scala> Option(3)
res5: Option[Int] = Some(3)
Option
对象具有一个apply
方法,它完全符合:
var myOptionalString = Option(session.get("foo"));
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