Option(null).isEmpty
Boolean = true

Some(null).isEmpty
Boolean = false



val s:String = null
s: String = null

val x = Option(s)
x: Option[String] = None

x.foreach(value => println("value="+value))
没有任何输出

val x2 = Some(s)
Some[String] = Some(null)

x2.foreach(value => println("value="+value))
有输出
value=null



Some(null).get
Null = null

Option(null).get
java.util.NoSuchElementException: None.get
 

Option(null).orNull
Null = null