8357286: (bf) Remove obsolete instanceof checks in CharBuffer.append

[bplb]

Remove some instanceof checks which are vestigial now that CharSequence itself defines getChars(int,int,char[],int).

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Issue

• JDK-8357286: (bf) Remove obsolete instanceof checks in CharBuffer.append (Bug - P4)

Reviewers

• Alan Bateman (@AlanBateman - Reviewer)

Reviewing

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[openjdk]

@bplb 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:

8357286: (bf) Remove obsolete instanceof checks in CharBuffer.append

Reviewed-by: alanb

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 16 new commits pushed to the master branch:

• 3b32f6a: 8344556: [Graal] compiler/intrinsics/bmi/* fail when AOTCache cannot be loaded
• 8f73357: 8358815: Exception event spec has stale reference to catch_klass parameter
• 4291582: 8357382: runtime/cds/appcds/aotClassLinking/BulkLoaderTest.java#aot fails with Xcomp and C1
• ... and 13 more: https://git.openjdk.org/jdk/compare/500a3a2d0af0a3f7cf58b909bbbc2aa25926d8b4...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.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

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[mlbridge]

Webrevs

• 01: Full - Incremental (cda92b2e)
• 00: Full (6f02b2cd)

[jaikiran]

Hello Brian, it looks like the Basic.java test has caught a genuine issue with this change:

java.lang.NullPointerException: Cannot invoke "java.lang.CharSequence.length()" because "csq" is null
	at java.base/java.nio.HeapCharBuffer.append(HeapCharBuffer.java:297)
	at java.base/java.nio.HeapCharBuffer.append(HeapCharBuffer.java:48)
	at Basic.test(Basic.java:340)
	at Basic.main(Basic.java:382)
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
	at java.base/java.lang.reflect.Method.invoke(Method.java:565)
	at com.sun.javatest.regtest.agent.MainActionHelper$AgentVMRunnable.run(MainActionHelper.java:335)
	at java.base/java.lang.Thread.run(Thread.java:1474)

[bplb]

Hello Brian, it looks like the Basic.java test has caught a genuine issue with this change:

Which Basic.java? The jdk_nio tests all passed on Linux.

[jaikiran]

Hello Brian, it looks like the Basic.java test has caught a genuine issue with this change:

Which Basic.java? The jdk_nio tests all passed on Linux.

The failure was from the GitHub actions jobs that are linked against this PR. For example here https://github.com/bplb/jdk/actions/runs/15573247306#summary-43854237657. The test appears to be java/lang/Appendable/Basic.

[bplb]

The test appears to be java/lang/Appendable/Basic.

Thanks.

[AlanBateman]

Updated patch looks okay, I assume at least tier1-3 have been run with the changes.

[bplb]

/integrate

[openjdk]

Going to push as commit 0dd7c69.
Since your change was applied there have been 37 commits pushed to the master branch:

• 66535fe: 8358701: Remove misleading javax.management.remote API doc wording about JMX spec, and historic link to JMXMP
• db7af2b: 8349550: Improve SASL random usage
• 9982995: 8358819: The first year is not displayed correctly in Japanese Calendar
• ... and 34 more: https://git.openjdk.org/jdk/compare/500a3a2d0af0a3f7cf58b909bbbc2aa25926d8b4...master

Your commit was automatically rebased without conflicts.

[openjdk]

@bplb Pushed as commit 0dd7c69.

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