Identify remaining final field mutations

[sarahchen6]

What Does This Do

Identify remaining final field mutations in library

Motivation

Prepare for JEP 500 which will disallow these mutations in a future JDK release

Additional Notes

Contributor Checklist

• Format the title according to the contribution guidelines
• Assign the type: and (comp: or inst:) labels in addition to any other useful labels
• Avoid using close, fix, or any linking keywords when referencing an issue
  Use solves instead, and assign the PR milestone to the issue
• Update the CODEOWNERS file on source file addition, migration, or deletion
• Update public documentation with any new configuration flags or behaviors
• Once approved, use merge queue to merge the PR

Jira ticket: [PROJ-IDENT]

[datadog-prod-us1-4]

🎯 Code Coverage (details)
• Patch Coverage: 100.00%
• Overall Coverage: 68.49% (+10.96%)

_{This comment will be updated automatically if new data arrives.
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[pr-commenter]

Debugger benchmarks

Parameters

	Baseline	Candidate
baseline_or_candidate	baseline	candidate
ci_job_date	1784813680	1784814026
end_time	2026-07-23T13:36:05	2026-07-23T13:41:52
git_branch	master	sarahchen6/identiy-test-final-field-mutations
git_commit_sha	507d52c	ed748e6
start_time	2026-07-23T13:34:41	2026-07-23T13:40:27

See matching parameters

	Baseline	Candidate
ci_job_id	1886895453	1886895453
ci_pipeline_id	126515774	126515774
cpu_model	Intel(R) Xeon(R) Platinum 8259CL CPU @ 2.50GHz	Intel(R) Xeon(R) Platinum 8259CL CPU @ 2.50GHz
git_commit_date	1784813129	1784813129

Summary

Found 0 performance improvements and 0 performance regressions! Performance is the same for 9 metrics, 6 unstable metrics.

See unchanged results

scenario	Δ mean agg_http_req_duration_min	Δ mean agg_http_req_duration_p50	Δ mean agg_http_req_duration_p75	Δ mean agg_http_req_duration_p99	Δ mean throughput
scenario:noprobe	unstable [-21.154µs; +42.096µs] or [-7.287%; +14.500%]	unstable [-34.286µs; +54.459µs] or [-10.259%; +16.295%]	unstable [-43.260µs; +67.190µs] or [-12.360%; +19.197%]	unstable [-95.365µs; +386.369µs] or [-8.202%; +33.231%]	same
scenario:basic	same	same	same	unstable [-141.060µs; +105.732µs] or [-13.296%; +9.966%]	unstable [-147.355op/s; +147.355op/s] or [-5.894%; +5.894%]
scenario:loop	same	same	same	same	same

Request duration reports for reports

gantt
    title reports - request duration [CI 0.99] : candidate=None, baseline=None
    dateFormat X
    axisFormat %s
section baseline
noprobe (334.202 µs) : 304, 364
.   : milestone, 334,
basic (295.676 µs) : 289, 302
.   : milestone, 296,
loop (8.984 ms) : 8979, 8988
.   : milestone, 8984,
section candidate
noprobe (344.289 µs) : 293, 396
.   : milestone, 344,
basic (295.129 µs) : 288, 302
.   : milestone, 295,
loop (8.995 ms) : 8974, 9016
.   : milestone, 8995,

Loading

• baseline results

Scenario	Request median duration [CI 0.99]
noprobe	334.202 µs [304.276 µs, 364.128 µs]
basic	295.676 µs [289.286 µs, 302.065 µs]
loop	8.984 ms [8.979 ms, 8.988 ms]

• candidate results

Scenario	Request median duration [CI 0.99]
noprobe	344.289 µs [292.68 µs, 395.897 µs]
basic	295.129 µs [288.014 µs, 302.244 µs]
loop	8.995 ms [8.974 ms, 9.016 ms]

[dd-octo-sts]

🟢 Java Benchmark SLOs — All performance SLOs passed

Suite	Status
Startup	🟢 pass

SLO thresholds are defined here based on automatically generated metrics. A warning is raised when results are within 5% of the threshold.

PR vs. master results

Scenario	Candidate	master	Δ (95% CI of mean)
startup:insecure-bank:iast:Agent	13.91 s	13.94 s	[-0.9%; +0.5%] (no difference)
startup:insecure-bank:tracing:Agent	13.01 s	13.01 s	[-0.8%; +0.8%] (no difference)
startup:petclinic:appsec:Agent	16.95 s	16.89 s	[-0.4%; +1.1%] (no difference)
startup:petclinic:iast:Agent	16.98 s	17.03 s	[-1.0%; +0.5%] (no difference)
startup:petclinic:profiling:Agent	16.84 s	16.84 s	[-1.2%; +1.1%] (no difference)
startup:petclinic:sca:Agent	17.05 s	16.63 s	[+1.8%; +3.3%] (significantly worse)
startup:petclinic:tracing:Agent	16.21 s	16.17 s	[-0.4%; +1.0%] (no difference)

Commit: ed748e6b · CI Pipeline · Benchmarking Platform UI

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Load and DaCapo benchmarks can be triggered manually in the GitLab pipeline. Results will appear in the Benchmarking Platform UI after completion.

[datadog-prod-us1-4]

More details

The PR only appends JEP 500 TODO comments to five existing test-only reflective assignments; executable statements and surrounding behavior are unchanged. Direct adversarial checks for object, Duration, and null field replacement passed, while the repository tests could not start because the environment lacks the Java 25 toolchain requested by the build.

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[sarahchen6]

/merge

[gh-worker-devflow-routing-ef8351]

View all feedbacks in Devflow UI.

2026-07-23 15:13:19 UTC ℹ️ Start processing command /merge

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2026-07-23 15:13:25 UTC ℹ️ MergeQueue: pull request added to the queue

The expected merge time in master is approximately 1h (p90).

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2026-07-23 16:10:02 UTC ℹ️ MergeQueue: This merge request was merged