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Moderne licensed

Use Empty Array for Collection.toArray()

Recipe IDorg.openrewrite.staticanalysis.ReplaceCollectionToArrayArgWithEmptyArrayArtifactorg.openrewrite.recipe:rewrite-static-analysis

Changes new array creation with Collection#toArray(T[]) to use an empty array argument, which is better for performance. According to the Collection#toArray(T[]) documentation: > If the collection fits in the specified array, it is returned therein. However, although it's not intuitive, allocating a right-sized array ahead of time to pass to the API appears to be generally worse for performance according to benchmarking and JVM developers due to a number of implementation details in both Java and the virtual machine. H2 achieved significant performance gains by switching to empty arrays instead pre-sized ones.

Single recipeMSAL

Add to your build

Get a download tokenThis recipe is Moderne licensed, so the token must belong to a Moderne customer. It replaces YOUR_DOWNLOAD_TOKEN below.

~/.gradle/gradle.properties

codeGenomeUsername=you@example.com
codeGenomeToken=YOUR_DOWNLOAD_TOKEN

build.gradle.kts

plugins {
    id("org.openrewrite.rewrite") version("latest.release")
}

rewrite {
    activeRecipe("org.openrewrite.staticanalysis.ReplaceCollectionToArrayArgWithEmptyArray")
}

repositories {
    mavenCentral()
    maven {
        url = uri("https://artifacts.codegenomeproject.org/maven")
        credentials {
            username = providers.gradleProperty("codeGenomeUsername").get()
            password = providers.gradleProperty("codeGenomeToken").get()
        }
    }
}

dependencies {
    rewrite("org.openrewrite.recipe:rewrite-static-analysis:2.44.0")
}

Then run

./gradlew rewriteRun

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.staticanalysis.ReplaceCollectionToArrayArgWithEmptyArray

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

mod config recipes jar install org.openrewrite.recipe:rewrite-static-analysis:RELEASE

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