RFR: 8357653: Inner classes of type parameters emitted as raw types in signatures [v14]

[Maurizio Cimadamore]

On Thu, 10 Jul 2025 13:32:31 GMT, Aggelos Biboudis <abimpoudis at openjdk.org> wrote:

>> There are various occasions that the qualifier of an _inner type_ needs to be normalized. 
>> 
>> Briefly:
>> 
>> - This occurs when there is an explicit type application in the signature of the method or a type application operation or when type checking an expression operation (e.g., `G.Getter` in the first example, `M.B<?>` in the second example). 
>> - The reference to an inner type may not be explicitly qualified (e.g., `B<?>` which is not qualified but its type needs be calculated as seen from `A<String>.B<?>`).
>> 
>> Semi-formally: 
>> 
>> - A type reference is simple name `R`:
>> 
>>   - `R` is a non-inner class type, nothing to do
>>   - `R` is an inner class type, we need to find an implicit type qualifier `S<T>.R`, where `S` is the class in which `R` is enclosed
>>   - `R` is an array type `A[]`, repeat the analysis for the simple type name `A`, and then use the implicit type qualifier to rewrite the array
>> 
>> - A type reference is a qualified name `Q.R`
>>   
>>   - find the supertype of `Q`, namely `S<T>`, where `S` is the class in which `R` is enclosed
>> 
>> 
>> 
>> // example 1
>> static class Usage1<T, G extends Getters<T>> {
>>   public T test(G.Getter getter) {
>>       return getter.get();
>>   }
>> }
>> 
>> // example 2
>> class A<T> {
>>   protected class B<V> {}
>> 
>>   public static <T, M extends A<T>> void f(Object g) {
>>     @SuppressWarnings("unchecked")
>>     M.B<?> mapping = (M.B<?>) g;
>>   }
>> }
>> 
>> // example 3
>> class A<T> {
>>     class B<W> {
>>         public T rett() { return null; }
>>     }
>> }
>> 
>> class C extends A<String> {
>>     static class D {
>>         {
>>             B<?> b = null;
>>             String s = b.rett();
>>         }
>>     }
>> }
>
> Aggelos Biboudis has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Re-inline methods

The code looks good to go. If you want to add more examples or comments in the javadoc, that might be useful, but the PR as is looks good.

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Marked as reviewed by mcimadamore (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/25451#pullrequestreview-3006738477