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Moderne licensed

Prefer Map.of(..)

Recipe IDorg.openrewrite.java.migrate.util.MigrateCollectionsSingletonMap
Artifactorg.openrewrite.recipe:rewrite-migrate-java

Prefer Map.of(..) instead of using Collections.singletonMap() in Java 9 or higher. Note that the resulting Map is not behaviorally equivalent: Map.of(..) throws NullPointerException when probed with containsKey(null), containsValue(null), or get(null), whereas Collections.singletonMap(..) returns false/null.

Single recipeMSAL

Usage

This recipe has no required configuration options. You’ll need the Moderne CLI configured before running the command below.

mod run . --recipe org.openrewrite.java.migrate.util.MigrateCollectionsSingletonMap

If the recipe isn’t available locally, install it with:

mod config recipes jar install org.openrewrite.recipe:rewrite-migrate-java:3.41.0

Data tables

Structured output this recipe can produce.

  • Source files that had resultsSource files that were modified by the recipe run.org.openrewrite.table.SourcesFileResults
  • Source files that had search resultsSearch results that were found during the recipe run.org.openrewrite.table.SearchResults
  • Source files that errored on a recipeThe details of all errors produced by a recipe run.org.openrewrite.table.SourcesFileErrors
  • Recipe performanceStatistics used in analyzing the performance of recipes.org.openrewrite.table.RecipeRunStats