On Thu, 21 Nov 2024 00:20:36 GMT, Daniel Gredler <[email protected]> wrote:
> When `LineBreakMeasurer` is used to break text into lines, internally it uses > `TextMeasurer` and `TextLine` to do the job. In the common case, > `TextLine.getComponents(...)` allocates a `TextLineComponent[]` with room for > a single array entry, and passes it to `TextLine.createComponentsOnRun(...)`, > which fills the array and returns it, optionally resizing to a larger array > if necessary, after which the array is resized back down to actual size (if > necessary). > > Unfortunately `TextLine.createComponentsOnRun(...)` is too eager in > allocating larger arrays. In the most common case of a single component, this > means that a single-element array is allocated, then a 9-element array is > allocated (via `expandArray(...)`), and then another single-element array is > allocated (to shrink the array back to actual size). Only one array > allocation is necessary in this common case, and no array copying is needed. This pull request has now been integrated. Changeset: f6021a9c Author: Daniel Gredler <[email protected]> URL: https://git.openjdk.org/jdk/commit/f6021a9c34da877bf954f5b90b4233949ec0ffc7 Stats: 3 lines in 1 file changed: 0 ins; 0 del; 3 mod 8344668: Unnecessary array allocations and copying in TextLine Reviewed-by: honkar, azvegint, prr ------------- PR: https://git.openjdk.org/jdk/pull/22288
