Fix ClassCastException on parenthesized initializers in var recipes#1064
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knutwannheden merged 1 commit intomainfrom Apr 17, 2026
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`UseVarForConstructors` and `UseVarForGenericMethodInvocations` unwrap the initializer for local `instanceof` checks but pass the original `VariableDeclarations` (still wrapping `J.Parentheses`) to downstream casts/`transformToVar`, which re-fetch and cast the raw initializer. Rewrite the declaration to use the unwrapped initializer (preserving the original prefix) before handing it off.
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…30.1 to 3.34.0 [skip ci] Bumps [org.openrewrite.recipe:rewrite-migrate-java](https://github.com/openrewrite/rewrite-migrate-java) from 3.30.1 to 3.34.0. Release notes *Sourced from [org.openrewrite.recipe:rewrite-migrate-java's releases](https://github.com/openrewrite/rewrite-migrate-java/releases).* > 3.34.0 > ------ > > What's Changed > -------------- > > * Ensure `case` always has a space before the label in `IfElseIfConstructToSwitch` by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1071](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1071) > * Add `UsePredicateNot` to replace cast-and-negate with `Predicate.not(..)` by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1072](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1072) > > **Full Changelog**: <openrewrite/rewrite-migrate-java@v3.33.0...v3.34.0> > > 3.33.1 > ------ > > **Full Changelog**: <openrewrite/rewrite-migrate-java@v3.33.0...v3.33.1> > > 3.33.0 > ------ > > What's Changed > -------------- > > * Add URLEqualsHashCodeRecipes to Java best practices by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1058](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1058) > * Add --add-opens JVM args to surefire/failsafe for Java 25 by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1055](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1055) > * Collapse UpgradeDockerImageVersion cartesian via ChangeFrom capture by [`@jkschneider`](https://github.com/jkschneider) in [openrewrite/rewrite-migrate-java#1060](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1060) > * Add NoJodaTime to Java best practices by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1061](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1061) > * Support `copyOf` migration for Guava by [`@greg-at-moderne`](https://github.com/greg-at-moderne) in [openrewrite/rewrite-migrate-java#1062](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1062) > * Rename `_` identifier to `__` for Java ≤ 8 source files by [`@Jenson3210`](https://github.com/Jenson3210) in [openrewrite/rewrite-migrate-java#1063](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1063) > * Fix `ClassCastException` on parenthesized initializers in `var` recipes by [`@knutwannheden`](https://github.com/knutwannheden) in [openrewrite/rewrite-migrate-java#1064](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1064) > * Gate Kotlin-based Java version cap on actual Kotlin sources by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1066](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1066) > * Fix `MigrateCollections*` template errors on complex expression contexts by [`@knutwannheden`](https://github.com/knutwannheden) in [openrewrite/rewrite-migrate-java#1067](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1067) > > **Full Changelog**: <openrewrite/rewrite-migrate-java@v3.32.1...v3.33.0> > > v3.32.1 > ------- > > What's Changed > -------------- > > * Remove parentheses from single unnamed lambda parameters by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1054](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1054) > * Skip Kotlin and Groovy files in ReplaceUnusedVariablesWithUnderscore by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1056](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1056) > > **Full Changelog**: <openrewrite/rewrite-migrate-java@v3.32.0...v3.32.1> > > 3.32.0 > ------ > > What's Changed > -------------- > > * Cap Java version at 24 for Kotlin <2.3 in UpgradeToJava25 by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1035](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1035) > * Inline JavaTemplate fields at their usage sites by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1036](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1036) > * Use `JavaTemplate.apply()` static method by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1037](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1037) > * Fix ClassCastException in UseVarForGenericMethodInvocations by [`@knutwannheden`](https://github.com/knutwannheden) in [openrewrite/rewrite-migrate-java#1039](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1039) > * Upgrade Mockito to 5.17.x in Java 25 migration recipe by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1041](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1041) > * Migrate Mojarra and Glassfish JSF dependencies to Jakarta Faces by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1040](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1040) > * Upgrade jakarta.annotation-api to 3.0.x in Jakarta EE 11 recipe by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1042](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1042) > * Move type-use annotations to array brackets during JSpecify migration by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1038](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1038) > * Add explicit casts for visitor visit() return type by 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[openrewrite/rewrite-migrate-java#1045](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1045) > * Fix `AddMissingMethodImplementation` generating stubs for inherited methods by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1051](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1051) > * Add EnableLombokAnnotationProcessor to LombokBestPractices by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1052](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1052) ... (truncated) Commits * [`61c1777`](openrewrite/rewrite-migrate-java@61c1777) Extract documentation examples from tests * [`95028a5`](openrewrite/rewrite-migrate-java@95028a5) Add `UsePredicateNot` to replace cast-and-negate with `Predicate.not(..)` ([#1](https://redirect.github.com/openrewrite/rewrite-migrate-java/issues/1)... * [`a58b8b2`](openrewrite/rewrite-migrate-java@a58b8b2) Ensure `case` always has a space before the label in `IfElseIfConstructToSwit... * [`eac4344`](openrewrite/rewrite-migrate-java@eac4344) Fix `MigrateCollections*` template errors on complex expression contexts ([#1067](https://redirect.github.com/openrewrite/rewrite-migrate-java/issues/1067)) * [`0ca5cc8`](openrewrite/rewrite-migrate-java@0ca5cc8) Extract documentation examples from tests * [`968a22f`](openrewrite/rewrite-migrate-java@968a22f) Gate Kotlin-based Java version cap on actual Kotlin sources ([#1066](https://redirect.github.com/openrewrite/rewrite-migrate-java/issues/1066)) * [`a471dd1`](openrewrite/rewrite-migrate-java@a471dd1) [Auto] SDKMAN! Java candidates as of 2026-04-20T1116 * [`3b7b950`](openrewrite/rewrite-migrate-java@3b7b950) Fix `ClassCastException` on parenthesized initializers in `var` recipes ([#1064](https://redirect.github.com/openrewrite/rewrite-migrate-java/issues/1064)) * [`461609f`](openrewrite/rewrite-migrate-java@461609f) Rename `_` identifier to `__` for Java ≤ 8 source files ([#1063](https://redirect.github.com/openrewrite/rewrite-migrate-java/issues/1063)) * [`634e7d9`](openrewrite/rewrite-migrate-java@634e7d9) Support `copyOf` migration for Guava ([#1062](https://redirect.github.com/openrewrite/rewrite-migrate-java/issues/1062)) * Additional commits viewable in [compare view](openrewrite/rewrite-migrate-java@v3.30.1...v3.34.0) [](https://docs.github.com/en/github/managing-security-vulnerabilities/about-dependabot-security-updates#about-compatibility-scores) Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. 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Motivation
UseVarForConstructorscrashes withClassCastException: J$Parentheses cannot be cast to J$NewClasswhen the variable initializer is a parenthesizednewexpression:The recipe unwraps the initializer locally for the
instanceof J.NewClasscheck, but then hands the originalVariableDeclarations(still wrappingJ.Parentheses) toDeclarationCheck.transformToVar, which re-fetches the raw initializer and casts it toJ.NewClass.UseVarForGenericMethodInvocationshas the same latent bug — it unwraps for theinstanceof J.MethodInvocationcheck but then casts the raw initializer toJ.MethodInvocationfor further inspection.The other sibling recipes that call
DeclarationCheck.transformToVar(UseVarForObject,UseVarForGenericsConstructors,UseVarForPrimitive,UseVarForTypeCast) are not affected — they either don't unwrap, bail out early on parentheses, or use a lambda parameter type ofExpression.Example
Before — crashes:
After:
(Surplus parentheses are dropped as part of the transformation.)
Summary
vdto use the unwrapped initializer (preserving the original prefix) before callingDeclarationCheck.transformToVarinUseVarForConstructorsandUseVarForGenericMethodInvocations.transformToVar, because the transformer lambda's signature commits the caller to a specific expression type — silently unwrapping intransformToVarwould drop parens from outputs whose callers didn't request that.Test plan
UseVarForConstructorsTest#parenthesizedConstructorInitializerreproducing the originalClassCastException; confirmed it failed onmainwith the same stack and passes after the fix.UseVarForGenericMethodInvocationsTest#parenthesizedMethodInvocationInitializerreproducing the analogous crash for that recipe; confirmed it failed onmainand passes after the fix../gradlew testis green.