RFR: JDK-8298200 Clean up raw type warnings in javafx.beans.property.* and com.sun.javafx.property.* [v2]

[John Hendrikx]

On Sat, 10 Dec 2022 08:03:27 GMT, John Hendrikx <jhendrikx at openjdk.org> wrote:

>> I was just going to write that now that I look at it, this is a list comparison according to `List::equals`. No need to redo the whole logic..
>> 
>> About the validity of the comparison, `ReadOnlyListProperty` also implements `List`:
>> 
>> ReadOnlyListProperty<E> extends ListExpression<E>
>>   ListExpression<E> implements ObservableListValue<E>
>>     ObservableListValue<E> extends ObservableObjectValue<ObservableList<E>>, ObservableList<E>
>>       ObservableList<E> extends List<E>, Observable
>> 
>> So... it's also a list.
>
>> So... it's also a list.
> 
> I think it's a big mess, you can already see that in the hierarchy, extending both `ObservableObjectValue<ObservableList<E>>` (which is `ObservableValue<T>`) but also being a `ObservableList<E>`.  One or the other is going to break; either it is a property containing a list, or it is a list, it can't be both.
> 
> Either I can do:
> 
>      listProperty.equals(normalList);
> 
> or:
> 
>      listProperty.equals(aNormalPropertyContainingAList);
> 
> It looks like the first was chosen (I suppose because the `List` interface defines `equals` in that way) and the 2nd case will break (and is unfixable as equals needs to be symmetric).
> 
> Looking a bit further, I think extending `ObservableObjectValue<ObservableList<E>>` was a mistake here. It's also what contributes to making the collection properties so confusing (ie. you can replace all elements, or you can replace the entire list, which are two different actions that require two different forms of listeners) -- no other properties allow you to replace it's "container" -- ie. if properties had used an `AtomicReference` internally to store their value, they would not offer me the option to replace either the entire `AtomicReference` or only the value of the reference.

I've adjusted it now to be a bit more modern Java as per your suggestion.

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PR: https://git.openjdk.org/jfx/pull/969