Improve JSON component

[PerfectSlayer]

What Does This Do

This PR improves the JSON component by:

• Simplifying the writer size capability - relying on the underlying output stream size rather than introducing duplicate counting
• Introducing mapping capabilities compatible with the existing writer API - this is not part as the writer API as the mapping as its own logic
• Fix JSON writer usage

Motivation

Simplify the code and avoid duplicate output stream and byte array allocations.

Additional Notes

This PR is a follow up of #12052.

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: APMLP-1620

[datadog-datadog-us1-prod]

The payload dispatcher now serializes trace, span, and parent IDs as JSON strings even though the file format requires numeric fields, and the existing dispatcher test would reject this output. Separately, the new byte-size check reads an unflushed UTF-8 encoder buffer, so OTLP payload limits can be exceeded before the collector notices.

_{📊 Validated against 2 scenarios · Open Bits AI session}

_{🤖 Datadog Autotest · Commit bcd1db5 · What is Autotest? · @DataDog review to ask questions · Any feedback? Reach out in #autotest}

[chatgpt-codex-connector]

💡 Codex Review

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Reviewed commit: bcd1db5cab

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[datadog-datadog-us1-prod]

🎯 Code Coverage (details)
• Patch Coverage: 85.45%
• Overall Coverage: 57.45% (-0.24%)

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🔗 Commit SHA: 3db42b6 | Docs | Datadog PR Page | Give us feedback!}

[datadog-datadog-us1-prod]

View session in Datadog

Bits Code status: ✅ Done

Comment @DataDog to request changes

[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	14.00 s	13.96 s	[-0.4%; +1.1%] (no difference)
startup:insecure-bank:tracing:Agent	12.89 s	12.99 s	[-1.4%; -0.1%] (maybe better)
startup:petclinic:appsec:Agent	16.87 s	16.81 s	[-0.8%; +1.5%] (no difference)
startup:petclinic:iast:Agent	16.41 s	16.84 s	[-7.0%; +1.9%] (no difference)
startup:petclinic:profiling:Agent	16.76 s	16.95 s	[-2.3%; +0.1%] (no difference)
startup:petclinic:sca:Agent	16.87 s	16.49 s	[+1.5%; +3.2%] (significantly worse)
startup:petclinic:tracing:Agent	16.05 s	16.02 s	[-0.7%; +1.0%] (no difference)

Commit: 3db42b68 · CI Pipeline · Benchmarking Platform UI

---

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

[sarahchen6]

Cool!

[bric3]

I would rename the PR to be more descriptive to the improvements.

Otherwise looks good to me

[PerfectSlayer]

I would rename the PR to be more descriptive to the improvements.

Any suggestion? Because I need to keep it short for the changelog while the 3 commits address different topics 😓

[PerfectSlayer]

/merge

[gh-worker-devflow-routing-ef8351]

View all feedbacks in Devflow UI.

2026-07-28 16:34:09 UTC ℹ️ Start processing command /merge

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2026-07-28 16:34:13 UTC ℹ️ MergeQueue: pull request added to the queue

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

---

2026-07-28 16:56:07 UTC ❌ MergeQueue: The build pipeline contains failing jobs for this merge request

Build pipeline has failing jobs for 1d5b3fb:

• config-inversion-linter
• check-instrumentation-naming
• build_tests: [:smokeTest, smoke, -Xms256M -Xmx1024M]
• build_tests: [:instrumentationLatestDepTest, latestdep]
• build_tests: [:profilingTest, profiling]
  ...

⚠️ Do NOT retry failed jobs directly (why?).

What to do next?

• Investigate the failures and when ready, re-add your pull request to the queue!
• If your PR checks are green, try to rebase/merge. It might be because the CI run is a bit old.
• Any question, go check the FAQ.

Details

Since those jobs are not marked as being allowed to fail, the pipeline will most likely fail.
Therefore, and to allow other builds to be processed, this merge request has been rejected and the pipeline got canceled.

[PerfectSlayer]

/merge

[gh-worker-devflow-routing-ef8351]

View all feedbacks in Devflow UI.

2026-07-28 17:16:24 UTC ℹ️ Start processing command /merge

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2026-07-28 17:16:29 UTC ℹ️ MergeQueue: pull request added to the queue

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

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2026-07-28 18:20:23 UTC ℹ️ MergeQueue: This merge request was merged