7169951: SwingSet2 throws NullPointerException with Nimbus L&F

[prsadhuk]

It is observed that if SwingSet2 is run in Nimbus L&F and
we drag the icon tool bar (which is floatable) out of the GUI Window
and Once the tool bar is detached, click on "Look & Feel" menu option to change to any L&F (say Java L&F)
it causes NPE due to font being null when getFontMetrics() is called

In other L&F, it uses the tabPane's font whereas in Nimbus font is obtained from getStyle().getFont() which returns null when toolbar is detached from the main window.
The proposed fix is to get tabPane's font if the font passed is null alike other L&Fs.

No regression test is made as it can be verified with SwingSet2..

---

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Issue

• JDK-7169951: SwingSet2 throws NullPointerException with Nimbus L&F

Reviewers

• Abhishek Kumar (@kumarabhi006 - Committer)
• Jayathirth D V (@jayathirthrao - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back psadhukhan! 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]

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[mlbridge]

Webrevs

• 00: Full (b8a3a6dd)

[mrserb]

It is unclear does the "getStyle().getFont()" always returns null for that component but we call it only for "floatable" toolbar. Or "getStyle().getFont()" starts to return null for the "floatable" toolbar. If it starts to return null then why does this happen? Are we sure that the "getStyle().getFont()" and "tabPane.getFont()" always returns the same font?

[prsadhuk]

getStyle().getFont() returns null as "getFontForState(context)" returns null which is because synth state for floating toolbar is invalid which is 0x201
getStyle().getFont()" and "tabPane.getFont()" in normal valid case returns same font which is javax.swing.plaf.FontUIResource[family=SansSerif,name=sansserif,style=plain,size=12]

[prsadhuk]

Any more comments on this fix?

[kumarabhi006]

Verified SwingSet2 floating toolbar with current fix.
I think copyright year can be updated else looks good to me.

[openjdk]

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

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

7169951: SwingSet2 throws NullPointerException with Nimbus L&F

Reviewed-by: abhiscxk, jdv

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At the time when this comment was updated there had been 744 new commits pushed to the master branch:

• a917fb3: 7033677: potential cast error in MemberEnter
• 6120319: 8302226: failure_handler native.core should wait for coredump to finish
• fef3eab: 8302734: Parallel: Remove unused LGRPSpace::_invalid_region
• ea5bfea: 8302661: Parallel: Remove PSVirtualSpace::is_aligned
• edf238b: 8302635: Race condition in HttpBodySubscriberWrapper when cancelling request
• cd77fcf: 8290822: C2: assert in PhaseIdealLoop::do_unroll() is subject to undefined behavior
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• 57fde75: 8302113: Improve CRC32 intrinsic with crypto pmull on AArch64
• b8c9d6c: 8302158: PPC: test/jdk/jdk/internal/vm/Continuation/Fuzz.java: AssertionError: res: false shouldPin: false
• dc55a7f: 8302202: Incorrect desugaring of null-allowed nested patterns
• ... and 734 more: https://git.openjdk.org/jdk/compare/ce6395a1356a3d1334aeffc70ac8e4f86dd81a4c...master

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[mrserb]

getStyle().getFont() returns null as "getFontForState(context)" returns null which is because synth state for floating toolbar is invalid which is 0x201 getStyle().getFont()" and "tabPane.getFont()" in normal valid case returns same font which is javax.swing.plaf.FontUIResource[family=SansSerif,name=sansserif,style=plain,size=12]

Where do we set this "invalid" state? Probably it is valid but we do not set the font property for it(or something like that)?

No regression test is made as it can be verified with SwingSet2..

I am not sure that people will test this usecase if we do not have an instruction to do that nor the tests.

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[prsadhuk]

/integrate

[openjdk]

Going to push as commit 0712adc.
Since your change was applied there have been 1225 commits pushed to the master branch:

• de1c12e: 8301012: [vectorapi]: Intrinsify CompressBitsV/ExpandBitsV and add the AArch64 SVE backend implementation
• 10fa7d1: 8304804: Remove develop flag G1VerifyCTCleanup
• 4acf20d: 8304809: Remove develop flag G1ExitOnExpansionFailure
• a5ffa07: 7026262: HttpServer: improve handling of finished HTTP exchanges
• 65e01da: 8304013: Add a fast, non-manual alternative to test/jdk/java/util/zip/ZipFile/TestTooManyEntries
• 38e1714: 8304258: x86: Improve the code generation of VectorRearrange with int and float
• 765a942: 8304136: Match allocation and free in sspi.cpp
• 3f59b75: 8304898: Fix Copyright Headers for JLink Source Files
• 501b606: 8298725: Add BitMap support for reverse iteration
• 9764948: 8273986: JEditorPane HTML Demo - Accessibility issues
• ... and 1215 more: https://git.openjdk.org/jdk/compare/ce6395a1356a3d1334aeffc70ac8e4f86dd81a4c...master

Your commit was automatically rebased without conflicts.

[openjdk]

@prsadhuk Pushed as commit 0712adc.

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