On Thu, 25 Aug 2022 13:50:19 GMT, Nir Lisker <nlis...@openjdk.org> wrote:
>> It's definitely a hypothetical case. `getChildren()` is called all over the >> place in JavaFX without a null check, so I see no reason for null checks >> here. > > Technically correct, although the [doc of > `getChildren()`](https://openjfx.io/javadoc/18/javafx.graphics/javafx/scene/Parent.html#getChildren()) > specifically says: > >> Note to subclasses: if you override this method, you must return from your >> implementation the result of calling this super method. The actual list >> instance returned from any getChildren() implementation must be the list >> owned and managed by this Parent. The only typical purpose for overriding >> this method is to promote the method to be public. > > So considering the case that an overriding method will return `null` is not > practical. > > As for a `null` child, I think that that's also not allowed. Considering that > a child can be added at most once to a scenegraph, it would mean that only 1 > `null` child is allowed. There might be more issues with `null` children. I > don't think there's a good reason to check for them. Yep, right. While it is possible to override `getChildren()` and return null, it will break everywhere so we can also omit the null check here. ------------- PR: https://git.openjdk.org/jfx/pull/841
