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…lvable types When JavaTemplate can't resolve a non-JDK type during switch case generation, it may not produce a J.VariableDeclarations AST node, causing pattern variable declarations to be dropped (e.g., `case Dog d ->` becomes `case Dog ->`). Fix by using positional case identification instead of type-checking the label, and reconstructing a proper J.VariableDeclarations from the original J.InstanceOf when the template parser fails to produce one. Fixes #1004
Jenson3210
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Mar 9, 2026
src/main/java/org/openrewrite/java/migrate/lang/IfElseIfConstructToSwitch.java
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Left a question/comment. Other that I think it looks okay. Too bad we do not have the original types of the code at hand during JavaTemplate generation as that would make this not necessary.
IfElseIfConstructToSwitch dropping pattern variables for unresolvable types
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…29.0 to 3.30.1 [skip ci] Bumps [org.openrewrite.recipe:rewrite-migrate-java](https://github.com/openrewrite/rewrite-migrate-java) from 3.29.0 to 3.30.1. Release notes *Sourced from [org.openrewrite.recipe:rewrite-migrate-java's releases](https://github.com/openrewrite/rewrite-migrate-java/releases).* > v3.30.1 > ------- > > What's Changed > -------------- > > * Fix Jackson 2.21+ compatibility for JREThrowableFinalMethods by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1010](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1010) > * Fix UpgradeToJava21 recipe ordering for switch expressions by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1012](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1012) > * Fix IfElseIfConstructToSwitch null safety regression by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1014](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1014) > * Fix Jetty EE9 dependencies by [`@evie-lau`](https://github.com/evie-lau) in [openrewrite/rewrite-migrate-java#1016](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1016) > * Cleanup Jetty EE10 recipes. Reorder… by [`@evie-lau`](https://github.com/evie-lau) in [openrewrite/rewrite-migrate-java#1017](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1017) > > **Full Changelog**: <openrewrite/rewrite-migrate-java@v3.30.0...v3.30.1> > > 3.30.0 > ------ > > What's Changed > -------------- > > * DataNucleus migrations by [`@jkschneider`](https://github.com/jkschneider) in [openrewrite/rewrite-migrate-java#998](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/998) > * Enable Lombok annotation processor during Java 17 upgrades by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#999](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/999) > * Use Groovy 4 by [`@greg-at-moderne`](https://github.com/greg-at-moderne) in [openrewrite/rewrite-migrate-java#1001](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1001) > * Avoid 9.1 Gradle version, should be 9.1.0 by [`@greg-at-moderne`](https://github.com/greg-at-moderne) in [openrewrite/rewrite-migrate-java#1002](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1002) > * Also upgrade maven-surefire-report-plugin to 3.5.x by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1006](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1006) > * Fix `IfElseIfConstructToSwitch` dropping pattern variables for unresolvable types by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1005](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1005) > * Fix Jackson 2.21+ conflicting creators in AWT recipes by [`@timtebeek`](https://github.com/timtebeek) in [openrewrite/rewrite-migrate-java#1007](https://redirect.github.com/openrewrite/rewrite-migrate-java/pull/1007) > > **Full Changelog**: <openrewrite/rewrite-migrate-java@v3.29.0...v3.30.0> Commits * [`b9375e4`](openrewrite/rewrite-migrate-java@b9375e4) Fix Jetty EE10 duplicate oldArtifactId on ChangeDependencies. Reorder and bri... * [`fd968d3`](openrewrite/rewrite-migrate-java@fd968d3) Fix Jetty EE9 dependencies ([#1016](https://redirect.github.com/openrewrite/rewrite-migrate-java/issues/1016)) * [`062873e`](openrewrite/rewrite-migrate-java@062873e) Fix IfElseIfConstructToSwitch null safety regression ([#1014](https://redirect.github.com/openrewrite/rewrite-migrate-java/issues/1014)) * [`7948b9a`](openrewrite/rewrite-migrate-java@7948b9a) Fix UpgradeToJava21 recipe ordering for switch expressions ([#1012](https://redirect.github.com/openrewrite/rewrite-migrate-java/issues/1012)) * [`c421ab1`](openrewrite/rewrite-migrate-java@c421ab1) Fix Jackson 2.21+ compatibility for JREThrowableFinalMethods ([#1010](https://redirect.github.com/openrewrite/rewrite-migrate-java/issues/1010)) * [`9826a90`](openrewrite/rewrite-migrate-java@9826a90) [Auto] SDKMAN! Java candidates as of 2026-03-16T1049 * [`5ff7443`](openrewrite/rewrite-migrate-java@5ff7443) Lombok Best Practices * [`6044cbb`](openrewrite/rewrite-migrate-java@6044cbb) OpenRewrite recipe best practices * [`114a5a2`](openrewrite/rewrite-migrate-java@114a5a2) Fix Jackson 2.21+ compatibility for AWT migration recipes ([#1007](https://redirect.github.com/openrewrite/rewrite-migrate-java/issues/1007)) * [`7661bb1`](openrewrite/rewrite-migrate-java@7661bb1) Fix `IfElseIfConstructToSwitch` dropping pattern variables for unresolvable t... * Additional commits viewable in [compare view](openrewrite/rewrite-migrate-java@v3.29.0...v3.30.1) [](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. You can also trigger a rebase manually by commenting `@dependabot rebase`. [//]: # (dependabot-automerge-start) [//]: # (dependabot-automerge-end) --- Dependabot commands and options You can trigger Dependabot actions by commenting on this PR: - `@dependabot rebase` will rebase this PR - `@dependabot recreate` will recreate this PR, overwriting any edits that have been made to it - `@dependabot show ignore conditions` will show all of the ignore conditions of the specified dependency - `@dependabot ignore this major version` will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this minor version` will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this dependency` will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself)
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Summary
IfElseIfConstructToSwitchconverts if-else-if chains withinstanceofchecks on non-JDK types, JavaTemplate's raw string substitution (#{}) can fail to produceJ.VariableDeclarationsAST nodes, causing pattern variable declarations to be dropped (e.g.,case Dog d ->becomescase Dog ->)instanceOfsiterator always advances correctly for pattern match casesbuildVariableDeclarations()fallback that reconstructs a properJ.VariableDeclarationsfrom the originalJ.InstanceOfwhen JavaTemplate fails to produce oneTest plan
All 14 existing
IfElseIfConstructToSwitchTesttests pass (includingnullCheckWithNonJdkTypesandthreeNonJdkTypes)No regressions in other tests
Fixes
IfElseIfConstructToSwitchfails to add variable declarations for custom types used ininstanceof#1004