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

John Hendrikx jhendrikx at openjdk.org
Sat Dec 10 08:05:59 UTC 2022


On Fri, 9 Dec 2022 20:19:57 GMT, Nir Lisker <nlisker at openjdk.org> wrote:

> 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.

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


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