8335802: Improve startup speed HexFormat uses boolean instead of enum

[wenshao]

The current HexFormat defines an Enum to represent LowerCase and UpperCase

class HexFormat {
    private enum Case {
        LOWERCASE,
        UPPERCASE
    }
}

This will cause the JVM to load one more class when it starts, which can be seen as follows

public class Startup {
    public static void main(String[] args) {}
}

java -verbose:class Startup

[0.094s][info][class,load] java.util.HexFormat$Case source: /Users/.../jdk/modules/java.base

There are only two cases here, which can be represented by boolean, which is clearer and can improve the startup speed a little bit.

---

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Issue

• JDK-8335802: Improve startup speed HexFormat uses boolean instead of enum (Enhancement - P4)

Reviewers

• Chen Liang (@liach - Reviewer)

Reviewing

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[openjdk]

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

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

8335802: Improve startup speed HexFormat uses boolean instead of enum

Reviewed-by: liach

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 69 new commits pushed to the master branch:

• 4f312d6: 8336152: Remove unused forward declaration in classLoadInfo.hpp
• 34d8562: 8335902: Parallel: Refactor VM_ParallelGCFailedAllocation and VM_ParallelGCSystemGC
• 2fc7eb4: 8155030: The Menu Mnemonics are always displayed for GTK LAF
• 559826c: 8332474: Tighten up ToolBox' JavacTask to not silently accept javac crash as a failure
• eec0e15: 8335619: Add an @APinote to j.l.i.ClassFileTransformer to warn about recursive class loading and ClassCircularityErrors
• 9b6f6c5: 8336082: Fix -Wzero-as-null-pointer-constant warnings in SimpleCompactHashtable
• 7a62032: 8336081: Fix -Wzero-as-null-pointer-constant warnings in JVMTypedFlagLimit ctors
• f677b90: 8267887: RMIConnector_NPETest.java fails after removal of RMI Activation (JDK-8267123)
• 1fe3ada: 8336284: Test TestClhsdbJstackLock.java/TestJhsdbJstackLock.java fails with -Xcomp after JDK-8335743
• c703d29: 8335710: serviceability/dcmd/vm/SystemDumpMapTest.java and SystemMapTest.java fail on Linux Alpine after 8322475
• ... and 59 more: https://git.openjdk.org/jdk/compare/b83766e59063a41ea8801ac9e7c15dce67727c62...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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[openjdk]

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[mlbridge]

Webrevs

• 01: Full - Incremental (9b1bf851)
• 00: Full (bf8d7cb4)

[liach]

The internal enum representation is an unnecessary abstraction; a boolean for uppercase is used for all public endpoints in isUpperCase and toString, so using the same boolean internally makes sense.

Do you think we should call this field ucase or uppercase?

[wenshao]

The internal enum representation is an unnecessary abstraction; a boolean for uppercase is used for all public endpoints in isUpperCase and toString, so using the same boolean internally makes sense.

Do you think we should call this field ucase or uppercase?

ucase is a name that has been used in this class. It is used in the formatOptDelimiter method. ucase is an abbreviation, but it is easy to understand. Using the name ucase also requires fewer changes than uppercase.

[liach]

Thanks for the detailed rationale and explanations! Runs fine on CI.

[wenshao]

/integate

[openjdk]

@wenshao Unknown command integate - for a list of valid commands use /help.

[wenshao]

/integrate

[openjdk]

@wenshao
Your change (at version 9b1bf85) is now ready to be sponsored by a Committer.

[liach]

/sponsor

[openjdk]

Going to push as commit 84c74ad.
Since your change was applied there have been 69 commits pushed to the master branch:

• 4f312d6: 8336152: Remove unused forward declaration in classLoadInfo.hpp
• 34d8562: 8335902: Parallel: Refactor VM_ParallelGCFailedAllocation and VM_ParallelGCSystemGC
• 2fc7eb4: 8155030: The Menu Mnemonics are always displayed for GTK LAF
• 559826c: 8332474: Tighten up ToolBox' JavacTask to not silently accept javac crash as a failure
• eec0e15: 8335619: Add an @APinote to j.l.i.ClassFileTransformer to warn about recursive class loading and ClassCircularityErrors
• 9b6f6c5: 8336082: Fix -Wzero-as-null-pointer-constant warnings in SimpleCompactHashtable
• 7a62032: 8336081: Fix -Wzero-as-null-pointer-constant warnings in JVMTypedFlagLimit ctors
• f677b90: 8267887: RMIConnector_NPETest.java fails after removal of RMI Activation (JDK-8267123)
• 1fe3ada: 8336284: Test TestClhsdbJstackLock.java/TestJhsdbJstackLock.java fails with -Xcomp after JDK-8335743
• c703d29: 8335710: serviceability/dcmd/vm/SystemDumpMapTest.java and SystemMapTest.java fail on Linux Alpine after 8322475
• ... and 59 more: https://git.openjdk.org/jdk/compare/b83766e59063a41ea8801ac9e7c15dce67727c62...master

Your commit was automatically rebased without conflicts.

[openjdk]

@liach @wenshao Pushed as commit 84c74ad.

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