Comparing effect of listener support api in SkinBase

SkinBaseObservableListFullSupport.java

    /**
     * Listening to listChanges of a list-valued property.
     * see https://bugs.openjdk.java.net/browse/JDK-8258777
     */
    @SuppressWarnings({ "rawtypes", "unchecked" })
    public static class SkinBaseObservableList extends SkinBase<ExampleControl> {

        public SkinBaseObservableList(ExampleControl control) {
            super(control);
            // list-valued observables need invalidation listener to re-wire content listener reliably
            registerInvalidationListener(control.itemsProperty(), p -> updateItemsContentListener());
            updateItemsContentListener();
        }

        // reference to items, needed to unregister listChangeListener
        private ObservableList items;

        private void updateItemsContentListener() {
            // rewire
            unregisterListChangeListeners(items);
            items = getSkinnable().itemsProperty().getValue();
            registerListChangeListener(items, (Consumer<Change<?>>) c -> itemsContentChanged(c));
            // update internal state
            itemsContentChanged(null);
        }

        private void itemsContentChanged(Change c) {
            // update internals based on list content
        }

    }

SkinBaseObservableListInvalidationSupport.java

    /**
     * Example of current changed api (added registerInvalidation, no listChange support) api.
     */
    @SuppressWarnings({ "rawtypes", "unchecked" })
    public static class SkinBaseObservableList2 extends SkinBase<ExampleControl> {

        private ListChangeListener itemsContentListener;
        private WeakListChangeListener weakItemsContentListener;

        public SkinBaseObservableList2(ExampleControl control) {
            super(control);
            // list-valued observables need invalidation listener to re-wire content listener reliably
            registerInvalidationListener(control.itemsProperty(), obs -> updateItemsContentListener());
            itemsContentListener = c -> itemsContentChanged(c);
            weakItemsContentListener = new WeakListChangeListener<>(itemsContentListener);
            updateItemsContentListener();
        }

        // reference to items, needed to unregister listChangeListener
        private ObservableList items;

        private void updateItemsContentListener() {
            // rewire
            if (items != null) {
                items.removeListener(weakItemsContentListener);
            }
            items = getSkinnable().itemsProperty().getValue();
            if (items != null) {
                items.addListener(weakItemsContentListener);
            }
            // update internal state
            itemsContentChanged(null);
        }

        private void itemsContentChanged(Change c) {
            // update internals based on list content
        }

        @Override
        public void dispose() {
            if (items != null) {
                items.removeListener(weakItemsContentListener);
                items = null;
            }
            super.dispose();
        }

    }
    

SkinBaseObservableListNoSupport.java

    /**
     * Example of current (registerChangeListener only) api.
     */
    @SuppressWarnings({ "rawtypes", "unchecked" })
    public static class SkinBaseObservableList extends SkinBase<ExampleControl> {

        private InvalidationListener itemsListener;
        private WeakInvalidationListener weakItemsListener;
        private ListChangeListener itemsContentListener;
        private WeakListChangeListener weakItemsContentListener;

        public SkinBaseObservableList(ExampleControl control) {
            super(control);
            // list-valued observables need invalidation listener to re-wire content listener reliably
            itemsListener = list -> updateItemsContentListener();
            weakItemsListener = new WeakInvalidationListener(itemsListener);
            control.itemsProperty().addListener(weakItemsListener);
            itemsContentListener = c -> itemsContentChanged(c);
            weakItemsContentListener = new WeakListChangeListener<>(itemsContentListener);
            updateItemsContentListener();
        }

        // reference to items, needed to unregister listChangeListener
        private ObservableList items;

        private void updateItemsContentListener() {
            // rewire
            if (items != null) {
                items.removeListener(weakItemsContentListener);
            }
            items = getSkinnable().itemsProperty().getValue();
            if (items != null) {
                items.addListener(weakItemsContentListener);
            }
            // update internal state
            itemsContentChanged(null);
        }

        private void itemsContentChanged(Change c) {
            // update internals based on list content
        }

        @Override
        public void dispose() {
            if (getSkinnable() == null) return;
            getSkinnable().itemsProperty().removeListener(weakItemsListener);
            if (items != null) {
                items.removeListener(weakItemsContentListener);
                items = null;
            }
            super.dispose();
        }

    }