On Thu, 9 Apr 2026 03:15:34 GMT, Charlie Schlosser <[email protected]> wrote:
> Fixes https://bugs.openjdk.org/browse/JDK-8181411 and > https://bugs.openjdk.org/browse/JDK-8380308 > > `TreeUtil.getItem` is used pervasively throughout `TreeView` and > `TreeTableView`, specifically `getTreeItem`. This performs a > depth-first-search (DFS) of the tree, and caches the target item. This is ok > for random access, but is slow for sequential access with a cold cache, as > each subsequent call to `getTreeItem` starts a new DFS from the root of the > tree. For `selectAll`, this has O(N^2) time complexity. > > This PR adds a stateful iterator that resumes the DFS from the previously > retrieved item, and caches each item during the traversal. This reduces the > time complexity `selectAll` case to O(N). > > This change revealed an otherwise harmless bug in the order of event handling > in the `invalidated()` method of the root property. > > Current behavior: > 1. `expandedItemCountChangeEvent` fires > 2. Focus model listener fires > 3. Focus model calls `getTreeItem`, `expandedItemCountDirty` is false, cache > miss, correct item returned > 5. `rootEvent` fires, sets `expandedItemCountDirty = true` > > The correct behavior would be to set `expandedItemCountDirty = true` before > the focus model calls getTreeItem. It works anyway because any item that is > not in the cache triggers a full DFS from the root, which is always valid. > > This PR: > 1. `expandedItemCountChangeEvent` fires > 2. `rootEvent` fires, sets `expandedItemCountDirty = true` > 3. Focus model listener fires > 4. Focus model calls `getTreeItem`, `expandedItemCountDirty` is true, > iterator resets, correct item returned > > This is fixed by using `expandedItemCountChangeEvent` instead of the super > type `treeNotificationEvent`. The subclass event types are processed before > their super counterparts, regardless of registration order. Now that they are > the same type, the order is correct. > > This behavior is already covered (and is motivated) by `TreeTableViewTest > > test_rt17522_focusShouldMoveWhenItemRemovedBeforeFocusIndex_1()` and > `TreeTableViewTest > > test_rt17522_focusShouldMoveWhenItemAddedAtFocusIndex_1()`. > > > > ┌─────────┬───────────────────┬──────────────────┬────────────────────────┬───────────────────────┐ > │ Items │ TreeView (before) │ TreeView (after) │ TreeTableView (before) │ > TreeTableView (after) │ > > ├─────────┼───────────────────┼──────────────────┼────────────────────────┼───────────────────────┤ > │ 64 │ 1ms │ 1ms │ 2ms │ > 2ms │ > ├─────────┼────────────────... This pull request has now been integrated. Changeset: e735e23a Author: Charlie Schlosser <[email protected]> Committer: Andy Goryachev <[email protected]> URL: https://git.openjdk.org/jfx/commit/e735e23ae730fefe622c61db4e04caf6831c0c16 Stats: 414 lines in 5 files changed: 347 ins; 33 del; 34 mod 8181411: Performance problem with TreeTableView selectAll() 8380308: TreeView: selection of many rows is slow Reviewed-by: angorya, mhanl ------------- PR: https://git.openjdk.org/jfx/pull/2142
