On Mon, 2 Oct 2023 14:47:59 GMT, Aggelos Biboudis <abimpou...@openjdk.org> wrote:
>> This is the first draft of a patch for Primitive types in patterns, >> instanceof, and switch (Preview). >> >> Draft spec here: >> https://cr.openjdk.org/~abimpoudis/instanceof/instanceof-20230913/specs/instanceof-jls.html > > Aggelos Biboudis has updated the pull request with a new target base due to a > merge or a rebase. The incremental webrev excludes the unrelated changes > brought in by the merge/rebase. The pull request contains four additional > commits since the last revision: > > - Merge branch 'master' into primitive-patterns > - Implement type pairs to exactnessMethod name > - Apply suggestions from code review > > Co-authored-by: Raffaello Giulietti <raffaello.giulie...@oracle.com> > - 8303374: Compiler Implementation for Primitive types in patterns, > instanceof, and switch (Preview) src/java.base/share/classes/java/lang/runtime/SwitchBootstraps.java line 228: > 226: currentTest = trueDef; > 227: } else if (currentLabelClass.isPrimitive()) { > 228: if (selectorType.isInstance(Object.class)) { As discussed offline, I believe this is wrong, and it should be replaced by `Class::equals`. That said, I think that "accidentally" you get the desired behavior here, as demonstrated by jshell: jshell> Byte.class.isInstance(Object.class) $6 ==> false jshell> Object.class.isInstance(Object.class) $8 ==> true So, this effectively acts as a test to check if the selector type is `Object`. Of course, since `isInstance` is used, spurious stuff is picked up as well: jshell> Class.class.isInstance(Object.class) $7 ==> true But this situation turns out to be non problematic, given that a primitive pattern is not applicable to a selector type Class. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/15638#discussion_r1343840181
