8258804: Collection.toArray() should use empty array

[XueleiFan]

Comparing to Collection.toArray(new T[size)), the Collection.toArray(new T[0]) seems faster, safer and contractually cleaner. In the update, the use of Collection.toArray(new T[size)) in the SunJSSE provider implementation is replaced with Collection.toArray(new T[0]).

Bug: https://bugs.openjdk.java.net/browse/JDK-8258804

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Progress

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Issue

• JDK-8258804: Collection.toArray() should use empty array

Reviewers

• Sean Mullan (@seanjmullan - Reviewer)

Download

$ git fetch https://git.openjdk.java.net/jdk pull/1861/head:pull/1861
$ git checkout pull/1861

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[openjdk]

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[mlbridge]

Webrevs

• 00: Full (da7ca04)

[seanjmullan]

Looks fine to me.

[openjdk]

@XueleiFan This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8258804: Collection.toArray() should use empty array

Reviewed-by: mullan

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 5 new commits pushed to the master branch:

• 9e463d1: 8258631: Remove sun.security.jgss.krb5.Krb5Util.getSubject()
• 0849117: 8256431: [PPC64] Implement Base64 encodeBlock() for Power64-LE
• 172af15: 8258284: clean up issues with nested ThreadsListHandles
• 3df6ec2: 8258682: compiler/intrinsics/mathexact/sanity tests fail with RepeatCompilation
• 1594372: 8258584: java/util/HexFormat/HexFormatTest.java fails on x86_32

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

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[dmlloyd]

If this level of performance improvement is justified, then would it not be better to use a constant empty array instead of constructing a new one each time?

[XueleiFan]

I think empty array construction could be optimized in the compiler layer.

[XueleiFan]

/integrate

[openjdk]

@XueleiFan Since your change was applied there have been 5 commits pushed to the master branch:

• 9e463d1: 8258631: Remove sun.security.jgss.krb5.Krb5Util.getSubject()
• 0849117: 8256431: [PPC64] Implement Base64 encodeBlock() for Power64-LE
• 172af15: 8258284: clean up issues with nested ThreadsListHandles
• 3df6ec2: 8258682: compiler/intrinsics/mathexact/sanity tests fail with RepeatCompilation
• 1594372: 8258584: java/util/HexFormat/HexFormatTest.java fails on x86_32

Your commit was automatically rebased without conflicts.

Pushed as commit 39e03a0.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.