docs(sdks): document FERN_JAVA_SKIP_FORMATTING for the Java generator

[devin-ai-integration]

Summary

The Java SDK generator normally runs a Gradle/Spotless formatting pass after it writes the generated code. That pass needs to reach services.gradle.org and plugins.gradle.org, so Java SDK generation failed outright on locked-down corporate networks even though the generated code is valid without formatting. Java SDK generator 4.18.0 adds FERN_JAVA_SKIP_FORMATTING, an environment variable that skips the pass entirely: generation succeeds on restricted networks and runs faster, with the tradeoff that output is unformatted until ./gradlew spotlessApply is run in the SDK repo.

Implements docs for: feat(java): add FERN_JAVA_SKIP_FORMATTING env var to skip Spotless (fern-api/fern#17367)

Pages changed

• fern/products/sdks/generators/java/configuration.mdx — new ## Skip code formatting section at the end of the page (deliberately outside the <ParamField> list, since this is an environment variable and not a generators.yml key): why the formatting pass needs network egress, the accepted truthy values (1, true, yes, on, any casing), a FERN_JAVA_SKIP_FORMATTING=true fern generate --group java-sdk example, CLI forwarding into the generator container / docker run -e, the 4.18.0 minimum, and that output is unformatted until ./gradlew spotlessApply runs.
• fern/products/sdks/deep-dives/self-hosted.mdx — one-line cross-reference where the page claims org verification and the image pull are the only network calls; the Java generator's Gradle hosts are the exception, linked to the new section.

No changelog entry: SDK changelogs are handled separately and the generator entry already exists at fern/products/sdks/generators/java/changelog/2026-08-11.mdx.

Validation: pre-commit run --files <changed> (Vale: 0 errors/warnings, only pre-existing suggestions on untouched lines) and fern check --warnings (0 errors; 6 pre-existing warnings).

Link to Devin session: https://app.devin.ai/sessions/81e55c4457e843e1b83accc97053386f

[devin-ai-integration]

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[github-actions]

🌿 Preview your docs: https://fern-preview-devin-1786640954-java-skip-formatting.docs.buildwithfern.com/learn

Here are the markdown pages you've updated:

• learn/sdks/deep-dives/self-hosted
• learn/sdks/generators/java/configuration