JDK-8304960: ObservableListBase should defer constructing ListChangeBuilder

[hjohn]

A 1200 Node application sees a 2/3rds reduction of ListChangeBuilder's created. Every Node for example has an ObservableList for style classes, and every Parent has one for stylesheets, which rarely if ever change.

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Progress

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Issue

• JDK-8304960: ObservableListBase should defer constructing ListChangeBuilder

Reviewers

• Andy Goryachev (@andy-goryachev-oracle - Committer)
• Marius Hanl (@Maran23 - Committer)
• Michael Strauß (@mstr2 - Committer)
• Kevin Rushforth (@kevinrushforth - Reviewer)

Reviewing

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$ git checkout pull/1075

Update a local copy of the PR:
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$ git pr checkout 1075

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[bridgekeeper]

👋 Welcome back jhendrikx! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[mlbridge]

Webrevs

• 00: Full (1168d7d7)

[andy-goryachev-oracle]

a good idea!

[kevinrushforth]

/reviewers 2

[openjdk]

@kevinrushforth
The total number of required reviews for this PR (including the jcheck configuration and the last /reviewers command) is now set to 2 (with at least 1 Reviewer, 1 Author).

[andy-goryachev-oracle]

the only place where this code might fail is when it gets accessed from multiple threads.

[hjohn]

the only place where this code might fail is when it gets accessed from multiple threads.

ListChangeBuilder itself is not thread safe :)

[Maran23]

Looks good to me too and makes sense.
This also aligns well with the listenerHelper, which is also created when needed.

[mstr2]

Looks good to me.

[kevinrushforth]

Looks good.

[openjdk]

@hjohn 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:

8304960: ObservableListBase should defer constructing ListChangeBuilder

Reviewed-by: angorya, mhanl, mstrauss, kcr

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 1 new commit pushed to the master branch:

• 2a5bf46: 8304924: [testbug] Skip failing tests on Linux

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[hjohn]

/integrate

[openjdk]

Going to push as commit c23d067.
Since your change was applied there has been 1 commit pushed to the master branch:

• 2a5bf46: 8304924: [testbug] Skip failing tests on Linux

Your commit was automatically rebased without conflicts.

[openjdk]

@hjohn Pushed as commit c23d067.

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