6463708: DefaultButtonModel.setMnemonic generates ChangeEvent for no change

[prsadhuk]

For a DefaultButtonModel, setMnemonic() generates a ChangeEvent even if the new value is the same as the old value (that is, even if nothing has changed).
Fix is to fire StateChange event only if the value has changed.

This is consistent with other places like
https://github.com/openjdk/jdk/blob/master/src/java.desktop/share/classes/javax/swing/colorchooser/DefaultColorSelectionModel.java#L103
https://github.com/openjdk/jdk/blob/master/src/java.desktop/share/classes/javax/swing/DefaultSingleSelectionModel.java#L79
https://github.com/openjdk/jdk/blob/master/src/java.desktop/share/classes/javax/swing/DefaultBoundedRangeModel.java#L309

---

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Issue

• JDK-6463708: DefaultButtonModel.setMnemonic generates ChangeEvent for no change

Reviewers

• Alexander Zvegintsev (@azvegint - Reviewer)
• Phil Race (@prrace - Reviewer)

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• 00: Full (cf010f2c)

[openjdk]

@prsadhuk 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:

6463708: DefaultButtonModel.setMnemonic generates ChangeEvent for no change

Reviewed-by: azvegint, prr

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At the time when this comment was updated there had been 186 new commits pushed to the master branch:

• ef8486a: 8286270: [java.desktop] Replace color search in XColors with a switch statement
• 62f2263: 8290861: Remove unused field URLJarFile.BUF_SIZE
• b28f9da: 8290688: Optimize x86_64 nmethod entry barriers
• 54854d9: 8256811: Delayed/missed jdwp class unloading events
• 75c1e99: 8289572: InputStream wrapping with BufferedInputStream is redundant in HttpTimestamper
• 7841e5c: 8290464: Optimize ResourceArea zapping on ResourceMark release
• e9f97b2: 8290489: Initial nroff manpage generation for JDK 20
• 59d85ba: 8290687: serviceability/sa/TestClassDump.java could leave files owned by root on macOS
• 66f59c2: 8290731: Clean up CDS handling of LambdaForm Species classes
• 0dda3c1: 8289275: Remove incorrect __declspec(dllimport) attributes from pointers in jdk.crypto.cryptoki
• ... and 176 more: https://git.openjdk.org/jdk/compare/46251bc6e248a19e8d78173ff8d0502c68ee1acb...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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[prsadhuk]

/integrate

[openjdk]

Going to push as commit f5d1b5b.
Since your change was applied there have been 261 commits pushed to the master branch:

• 30205bb: 8290966: G1: Record number of PLAB filled and number of direct allocations
• 86ef7b2: 8289046: Undefined Behaviour in x86 class Assembler
• d61c0c7: 8290497: some tests in com/sun/jdi fail on localized Windows platform
• 7ff1969: 8290067: Show stack dimensions in UL logging when attaching threads
• 257c71c: 8290062: Remove nmethodLocker for nmethods on-stack
• d9cb410: 8290466: Default to --with-source-date=current to avoid unmodified Hotspot recompilation
• acbe093: 8291559: x86: compiler/vectorization/TestReverseBitsVector.java fails
• 32d410a: 8290868: NMT: MallocSiteTable statistics improvements
• 3579024: 8288904: Incorrect memory ordering in UL
• 470c0eb: 8290740: Catalog not used when the handler is null
• ... and 251 more: https://git.openjdk.org/jdk/compare/46251bc6e248a19e8d78173ff8d0502c68ee1acb...master

Your commit was automatically rebased without conflicts.

[openjdk]

@prsadhuk Pushed as commit f5d1b5b.

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