On Wed, 3 Jan 2024 19:44:51 GMT, Pavel Rappo <[email protected]> wrote:
>> I think the best place, or least-bad place, to discuss the "modifier"
>> ordering of sealed/non-sealed would be an informative note on
>> Modifier.toString(int) -- "The sealed/non-sealed Java language modifiers are
>> not represented in the class file as access flags and thus not modeled by
>> this class [java.lang.reflect.Modifier] .... sealed/non-sealed should be
>> presented in the same location as final."
>>
>> Since it doesn't seem possible to do so, I did not attempt to relay
>> "non-sealed" information in this PR :-)
>
>> Since it doesn't seem possible to do so, I did not attempt to relay
>> "non-sealed" information in this PR :-)
>
> Naively, I thought that something like this is possible _in principle_; I
> might be mistaken though:
>
> diff --git a/src/java.base/share/classes/java/lang/Class.java
> b/src/java.base/share/classes/java/lang/Class.java
> index 851d65d06ad..014845860d0 100644
> --- a/src/java.base/share/classes/java/lang/Class.java
> +++ b/src/java.base/share/classes/java/lang/Class.java
> @@ -4771,6 +4771,30 @@ public boolean isSealed() {
> return getPermittedSubclasses() != null;
> }
>
> + private boolean isNonSealed() {
> + if (isSealed())
> + return false;
> + if (!isInterface() && Modifier.isFinal(getModifiers())) {
> + // unlike interface, class can be final
> + return false;
> + }
> + // if an ancestor is sealed, this class can either be non-sealed or
> final
> + return hasSealedAncestor(this);
> + }
> +
> + private boolean hasSealedAncestor(Class<?> clazz) {
> + var superclass = clazz.getSuperclass();
> + if (superclass != null) {
> + if (superclass.isSealed() || hasSealedAncestor(superclass))
> + return true;
> + }
> + for (var superinterface : clazz.getInterfaces()) {
> + if (superinterface.isSealed() ||
> hasSealedAncestor(superinterface))
> + return true;
> + }
> + return false;
> + }
> +
> private native Class<?>[] getPermittedSubclasses0();
>
> /*
Thanks @pavelrappo; I'll explore incorporating functionality like this into the
PR, probably next week.
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/17239#discussion_r1441020362
