Total pattern and null pattern
Tagir Valeev
amaembo at gmail.com
Wed Jul 20 08:54:45 UTC 2022
Hello!
Playing with Java 19, we stumbled upon this sample:
public class Main {
public static void main(String[] args) {
Integer x = null;
switch (x) {
case Integer i -> System.out.println(i);
case null -> System.out.println("null is supplied!");
}
}
}
Latest javac 19-ea says that this code is not compilable, as Integer i
is dominated by null. However, if we remove `case null`, then `case
Integer i` doesn't match the `null` (NPE is thrown). I find it strange
that `case Integer i` matches null when `case null` is supplied and
I'm forced to use `case null` before `case Integer i`. Is it expected
behavior?
With best regards,
Tagir Valeev.
More information about the amber-spec-experts
mailing list