On Wed, 21 Jan 2026 01:07:15 GMT, Michael Strauß <[email protected]> wrote:
>> Implementation of [enhanced property >> metadata](https://gist.github.com/mstr2/2fec0303fc440b8eaeb126befc76eb5c). >> >> ### New API >> This PR includes the following API additions: >> >> 1. `ReadOnlyProperty.getDeclaringClass()` and its default implementation. >> 2. The `javafx.beans.property.AttachedProperty` interface. >> 3. New constructors for all `Simple<*>Property` and `ReadOnly<*>Wrapper` >> classes, accepting the declaring class of the property. >> >> The declaring class is stored in a new field in the `Simple<*>Property` >> classes. If a legacy constructor is used that doesn't specify the declaring >> class, the `ReadOnlyProperty.getDeclaringClass()` default implementation is >> called the first time the `Simple<*>Property.getDeclaringClass()` method is >> called, and its result is stored for future retrieval. >> >> ### Testing >> For testing, this PR also includes the >> `test.util.property.PropertyMetadataVerifier` tool. It systematically tests >> all public and protected properties of a class, and ensures conformance to >> the following rules: >> * `ReadOnlyProperty.getBean()` returns the object instance of the enclosing >> class, or the target object instance if the property is an attached property. >> * `ReadOnlyProperty.getName()` returns the name of the property, which must >> correspond to the name of the property getter (excluding the word >> "Property"). >> * `ReadOnlyProperty.getDeclaringClass()` returns the enclosing class of the >> property getter. >> * The declaring class of a `Simple<*>Property` or `ReadOnly<*>Wrapper` must >> be specified in the constructor, not resolved at runtime. >> * `getBean()`, `getName()`, and `getDeclaringClass()` must not be overridden >> in subclasses of `Simple<*>Property` or `ReadOnly<*>Wrapper`. >> * An instance property does not implement `AttachedProperty`. >> * An instance property has a parameterless property getter. >> * An attached property implements `AttachedProperty`. >> * An attached property has a static single-argument property getter that >> accepts the target object. >> * `AttachedProperty.getTargetClass()` returns the class of the single >> parameter of the static property getter. >> * A property getter does not return an instance of `ReadOnly<*>Wrapper`, it >> returns the result of calling `ReadOnly<*>Wrapper.getReadOnlyProperty()`. >> >> Many properties in existing JavaFX classes violate the >> `PropertyMetadataVerifier` rules in some way or shape. This PR won't address >> these issues, this will be done in a future cleanup PR. > > Michael Strauß has updated the pull request incrementally with one additional > commit since the last revision: > > ReadOnlyProperty.getDeclaringClass() tests Perhaps it could help to think of attached properties as simple configuration on the node, not as temporary state owned by a container. You may not know which container a node will end up in, but you can still set things like a margin, or tell it to grow if it’s placed in a VBox. You might do the same for other container types it could live in. When the node is actually added to a parent, that parent just reads the properties it understands and ignores the rest. >From that point of view, it’s hard to justify why a container should remove >properties it didn’t set. Auto-removal makes moving a node between parents >lossy and surprising, because you lose configuration that was intentionally >added. A simpler rule is: keep attached properties on the node, let containers >use what applies to them, and only remove a property if the code that added it >explicitly does so. ------------- PR Comment: https://git.openjdk.org/jfx/pull/2015#issuecomment-3780792738
