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Add @Nullable to array element types that can hold null

io.moderne.nullability.infer.AddNullableToArrayElementType

Adds the JSpecify @Nullable annotation to the element type of a Java array whose elements are provably nullable, placing it on the component type to produce @Nullable String[] (the array's elements may be null) rather than String @Nullable [] (the array reference may be null). NullAway in JSpecify mode checks this position. An array declaration (field, local, parameter, or return type) is annotated when its initializer is an array literal containing a null element (String[] a = {null}, new String[]{x, null}) or when an element is assigned a provably-null value in the same method body (arr[i] = null). Conservative by design: it skips primitive-element arrays (whose elements can never be null), arrays whose element type already carries a nullability annotation, and non-Java sources (Kotlin and Groovy express element nullability in the type system, which their compilers already enforce).

Recipe source​

This recipe is only available to users of Moderne.

This recipe is available under the Moderne Proprietary License.

Used by​

This recipe is used as part of the following composite recipes:

Example​

Before​
class Test {
    String[] f = {null};
}
After​
import org.jspecify.annotations.Nullable;

class Test {
    @Nullable String[] f = {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 AddNullableToArrayElementType

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​

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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.