8337681: PNGImageWriter uses much more memory than necessary

[cost0much]

Clean backport. Fixes issue with the PNGImageWriter making unnecessary copies of raster and data buffers when PNG images are written. Passes GHA. Added test passes.

---

Progress

• JDK-8337681 needs maintainer approval
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8337681: PNGImageWriter uses much more memory than necessary (Bug - P4 - Approved)

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👋 Welcome back cost0much! 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.

[openjdk]

@cost0much This change now passes all automated pre-integration checks.

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

8337681: PNGImageWriter uses much more memory than necessary

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At the time when this comment was updated there had been 19 new commits pushed to the master branch:

• e853a44: 8368882: NPE during text drawing on machine with JP locale
• 77bd767: 8372465: Bump update version for OpenJDK: jdk-17.0.19
• 41990f8: 8327980: Convert javax/swing/JToggleButton/4128979/bug4128979.java applet test to main
• ... and 16 more: https://git.openjdk.org/jdk17u-dev/compare/cb258e5fba3767c343ed4bf54f3d2d6de6de2704...master

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[openjdk]

This backport pull request has now been updated with issue from the original commit.

[openjdk]

⚠️ @cost0much This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[mlbridge]

Webrevs

• 00: Full (f3971e28)

[cost0much]

/approval request Fixes issue with the PNGImageWriter making unnecessary copies of raster and data buffers when PNG images are written. Already backported to 21.0.8 and applies cleanly from JDK24. Passes GHA. Risk is low as client-lib change + previous 21 backport has gone multiple releases without issue.

[openjdk]

@cost0much
8337681: The approval request has been created successfully.

[cost0much]

/integrate

[openjdk]

@cost0much
Your change (at version f3971e2) is now ready to be sponsored by a Committer.