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Moderne licensed

Find SimpleDateFormat allocations inside loops

Recipe IDorg.openrewrite.kotlin.performance.FindSimpleDateFormatInLoops$KtRecipe
Artifactio.moderne.recipe:recipes-kotlin

SimpleDateFormat parses its pattern string in the constructor and is not thread-safe — allocating one per iteration is a common per-row hot spot. Hoist it out of the loop or use a thread-local cache (or migrate to DateTimeFormatter).

Single recipeProprietary

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.kotlin.performance.FindSimpleDateFormatInLoops$KtRecipe

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

mod config recipes jar install io.moderne.recipe:recipes-kotlin:0.2.0

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