8294626: Improve URL protocol lower casing

[cl4es]

Move a simple utility method from URL to the shared sun.net.util.URLUtil class, rename it for clarity and enhance it so that it returns the string literal if the protocol matches one of the tested variants. This helps reduce dependencies from bootstrap code on Locale while improving the performance and allocation pressure in certain applications.

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Issue

• JDK-8294626: Improve URL protocol lower casing

Reviewers

• Daniel Fuchs (@dfuch - Reviewer)

Reviewing

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[mlbridge]

Webrevs

• 02: Full - Incremental (2cec02e7)
• 01: Full - Incremental (0cf06bb6)
• 00: Full (9b7ca578)

[AlanBateman]

From a maintenance point of view it might be better to keep all special handling of these built-in schemes in URL rather than having them in two places. I'm thinking of isOverrideable, DefaultFactory.createURLStreamHandler and probably others. It's not a big issue, just a bit surprising to have special handling in code in two packages, if you see what I mean.

[dfuch]

I agree with Alan.

[cl4es]

URLUtil already exists, is used during bootstrap from non-java.net packages and would profit from reusing this lower case method. Making the method in URL public is a non-starter. I'd love having module-scoped visibility modifier (so we could share static utility methods without resorting to non-exported utility classes), but without that this was the best option to get the full benefit without duplicating the logic in places like URLUtil.urlNoFragString

[cl4es]

Should be all cleaned up now.

[dfuch]

LGTM now.

[openjdk]

@cl4es 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:

8294626: Improve URL protocol lower casing

Reviewed-by: dfuchs

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 53 new commits pushed to the master branch:

• 64da862: 8287597: List all preview features on the javadoc PREVIEW page
• b4e1e41: 8293000: Review running times of jshell regression tests
• 6d83482: 8293540: [Metrics] Incorrectly detected resource limits with additional cgroup fs mounts
• 6974978: 8294521: Parallel: Remove unused field in UpdateDensePrefixAndCompactionTask
• 81fda1b: 8294569: Remove CardTable::_last_valid_index
• 7c60e6d: 8293770: RISC-V: Reuse runtime call trampolines
• 9dce865: 8294115: JNI local refs exceeds capacity warning in NetworkInterface::getAll
• b030c7d: 8225235: Unused field defaultIndex in NetworkInterface
• a07975b: 8294519: (fs) java/nio/file/Files/CopyProcFile.java fails intermittenly due to unstable /proc/cpuinfo output
• 88062ee: 8293969: breakup the long signature in SystemDictionaryShared::is_supported_invokedynamic
• ... and 43 more: https://git.openjdk.org/jdk/compare/bc12e9553d30fbf849b5a681137a231ff083d901...master

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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[AlanBateman]

URLUtil already exists, is used during bootstrap from non-java.net packages and would profit from reusing this lower case method. Making the method in URL public is a non-starter. I'd love having module-scoped visibility modifier (so we could share static utility methods without resorting to non-exported utility classes), but without that this was the best option to get the full benefit without duplicating the logic in places like URLUtil.urlNoFragString

The update looks okay, I see Daniel has approved. Although special casing in a lower casing method is okay I think the main thing we have to avoid is doing special casing for built-in protocol handlers in several places, only because there are so many issues that can arise if we change it in one place and not another. There are also changes in the works that need to do more validation with the built-in protocol handlers.

[cl4es]

/integrate

[openjdk]

Going to push as commit 3efbd5f.
Since your change was applied there have been 56 commits pushed to the master branch:

• 052a924: 8294293: Remove unused _width and _newlines field in outputStream
• c2ce43c: 8291021: JFR: Only one finished state in ChunkHeader class
• f015733: 8294357: (tz) Update Timezone Data to 2022d
• 64da862: 8287597: List all preview features on the javadoc PREVIEW page
• b4e1e41: 8293000: Review running times of jshell regression tests
• 6d83482: 8293540: [Metrics] Incorrectly detected resource limits with additional cgroup fs mounts
• 6974978: 8294521: Parallel: Remove unused field in UpdateDensePrefixAndCompactionTask
• 81fda1b: 8294569: Remove CardTable::_last_valid_index
• 7c60e6d: 8293770: RISC-V: Reuse runtime call trampolines
• 9dce865: 8294115: JNI local refs exceeds capacity warning in NetworkInterface::getAll
• ... and 46 more: https://git.openjdk.org/jdk/compare/bc12e9553d30fbf849b5a681137a231ff083d901...master

Your commit was automatically rebased without conflicts.

[openjdk]

@cl4es Pushed as commit 3efbd5f.

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