java-best-practices.yml

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---
type: specs.openrewrite.org/v1beta/recipe
name: org.openrewrite.java.migrate.JavaBestPractices
displayName: Java best practices
description: >-
  Applies opinionated best practices for Java projects targeting Java 25.
  This recipe includes the full Java 25 upgrade chain plus additional improvements
  to code style, API usage, and third-party dependency reduction that go beyond
  what the version migration recipes apply.
tags:
  - java25
  - best-practices
preconditions:
  - org.openrewrite.Singleton
recipeList:
  # Upgrade to the latest Java version
  - org.openrewrite.java.migrate.UpgradeToJava25
  # Text blocks for strings without newlines (upgrade chain only does convertStringsWithoutNewlines: false)
  - org.openrewrite.java.migrate.lang.UseTextBlocks:
      convertStringsWithoutNewlines: true
  # Prefer Java standard library over Guava where possible
  - org.openrewrite.java.migrate.guava.NoGuava
  # JSpecify nullability annotations best practices
  - org.openrewrite.java.jspecify.JSpecifyBestPractices
  # Local variable type inference — targeted, non-controversial uses
  # NOTE: UseVarForGenericsConstructors and UseVarForGenericMethodInvocations must run
  # before UseDiamondOperator, as they need the explicit type arguments on constructors
  # to safely infer the type for var. Diamond would erase that information.
  - org.openrewrite.java.migrate.lang.var.UseVarForTypeCast
  - org.openrewrite.java.migrate.lang.var.UseVarForConstructors
  - org.openrewrite.java.migrate.lang.var.UseVarForGenericsConstructors
  - org.openrewrite.java.migrate.lang.var.UseVarForGenericMethodInvocations
  - org.openrewrite.java.migrate.lang.var.UseVarForPrimitive
  # Prefer modern Java collection factories and utilities
  - org.openrewrite.java.migrate.util.JavaUtilAPIs
  # Static analysis: bug prevention
  - org.openrewrite.staticanalysis.ReplaceWeekYearWithYear
  - org.openrewrite.staticanalysis.RemoveHashCodeCallsFromArrayInstances
  - org.openrewrite.staticanalysis.RemoveToStringCallsFromArrayInstances
  - org.openrewrite.staticanalysis.UseObjectNotifyAll
  - org.openrewrite.staticanalysis.RemoveCallsToSystemGc
  - org.openrewrite.staticanalysis.RemoveCallsToObjectFinalize
  # Static analysis: modernization and cleanup
  - org.openrewrite.staticanalysis.ReplaceLambdaWithMethodReference
  - org.openrewrite.staticanalysis.UseDiamondOperator
  - org.openrewrite.staticanalysis.UnnecessaryParentheses
  - org.openrewrite.staticanalysis.ReplaceStringBuilderWithString
  - org.openrewrite.staticanalysis.UseCollectionInterfaces
  - org.openrewrite.staticanalysis.CompareEnumsWithEqualityOperator
  - org.openrewrite.staticanalysis.CombineSemanticallyEqualCatchBlocks
  - org.openrewrite.staticanalysis.UseStringReplace
  - org.openrewrite.staticanalysis.UseStandardCharset
  - org.openrewrite.staticanalysis.UseSystemLineSeparator
  - org.openrewrite.staticanalysis.RemoveRedundantTypeCast
  - org.openrewrite.staticanalysis.ReplaceStackWithDeque
  - org.openrewrite.staticanalysis.UseListSort
  - org.openrewrite.staticanalysis.EqualsToContentEquals
  # Markdown documentation comments (JEP 467, Java 23+)
  - org.openrewrite.java.migrate.lang.JavadocToMarkdownDocComment
  # Cleanup imports left behind by transformations
  - org.openrewrite.java.RemoveUnusedImports