Skip to content

SYSTEM Cited by 1 source

NullAway (Uber)

NullAway is Uber's open-source static-analysis tool for Java null-safety. Built on top of ErrorProne; runs as a checker during compilation. Source: github.com/uber/NullAway.

Role in the wiki

NullAway is named in the 2024-12-18 Meta post alongside Nullsafe as the canonical "null-safe Java" tooling a large Android codebase would use before it could meaningfully translate to Kotlin: "by 'null safe' we mean code checked by a static analyzer such as Nullsafe or NullAway." Meta's pipeline assumes one of these classes of tool is in place on the Java side; otherwise, Kotlin translation injects NPEs at scale.

Shared limitation with Nullsafe

NullAway, like Nullsafe, is a static analyser, and "static analysis is only 100% effective for 100% code coverage." Both tools accept annotations; both can't prevent a non-annotated dependent from passing null into an annotated method. The Meta post argues this is why runtime nullability telemetry becomes necessary as a migration matures.

Seen in

Last updated · 319 distilled / 1,201 read