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Find nullable values passed to non-null parameters

io.moderne.nullability.search.FindNullableToNonNullArgument

Marks call arguments where a provably-nullable value is passed to a callee parameter that is not declared @Nullable. Inside a null-marked scope NullAway treats every unannotated parameter as non-null, so such a call is a NullAway error. A value is considered provably nullable when it is the null literal (directly, through a cast or parentheses, or via either branch of a ternary), a call to a method whose return is itself nullable, or a reference to a variable or field declared @Nullable. This is a search recipe: it only marks the offending arguments and does not modify the code. It is conservative — when the invoked method type cannot be resolved, the argument is left unmarked (a false negative rather than a false positive).

Recipe source​

This recipe is only available to users of Moderne.

This recipe is available under the Moderne Proprietary License.

Example​

Before​
class Test {
    void use(String s) {
    }

    void caller() {
        use(null);
    }
}
After​
class Test {
    void use(String s) {
    }

    void caller() {
        use(/*~~(Passing nullable value to non-null parameter (NullAway))~~>*/null);
    }
}

Usage​

This recipe has no required configuration options. Users of Moderne can run it via the Moderne CLI.

You will need to have configured the Moderne CLI on your machine before you can run the following command.

shell
mod run . --recipe FindNullableToNonNullArgument

If the recipe is not available locally, then you can install it using:

mod config recipes jar install io.moderne.recipe:rewrite-nullability:0.1.0

See how this recipe works across multiple open-source repositories​

Run this recipe on OSS repos at scale with the Moderne SaaS.

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Please contact Moderne for more information about safely running the recipes on your own codebase in a private SaaS.

Data Tables​

Source files that had results​

org.openrewrite.table.SourcesFileResults

Source files that were modified by the recipe run.

Column NameDescription
Source path before the runThe source path of the file before the run. null when a source file was created during the run.
Source path after the runA recipe may modify the source path. This is the path after the run. null when a source file was deleted during the run.
Parent of the recipe that made changesIn a hierarchical recipe, the parent of the recipe that made a change. Empty if this is the root of a hierarchy or if the recipe is not hierarchical at all.
Recipe that made changesThe specific recipe that made a change.
Estimated time savingAn estimated effort that a developer to fix manually instead of using this recipe, in unit of seconds.
CycleThe recipe cycle in which the change was made.