[7.x] Optimize allocations for List.copyOf and Set.copyOf
#79395
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
We can optimize away the array allocation just to call `List.of/Set.of` and instead create copies directly based the supplied collection.
arteam
added
>non-issue
:Core/Infra/Core
|
Pinging @elastic/es-core-infra (Team:Core/Infra) |
arteam
commented
Oct 18, 2021
| public static <T> java.util.Set<T> copyOf(Collection<? extends T> coll) { | ||
| return (java.util.Set<T>) Set.of(new HashSet<>(coll).toArray()); |
There was a problem hiding this comment.
This one looks especially bad, because we allocate a HashSet just to call toArray which exists for Collection.
|
Thanks, Dan! |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
We can remove the array allocation which required only to call
List.of/Set.ofand instead create copies directlybased the supplied collection.