Fix IfElseIfConstructToSwitch null safety regression#1014
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When converting instanceof chains to switch without an explicit null check, emit `case null, default` instead of just `default` to preserve instanceof's null-safe behavior. Previously, the recipe would generate code that throws NPE when the switched variable is null, unlike the original if-else chain.
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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
instanceofchains toswitchwithout an explicit null check, the recipe now emitscase null, defaultinstead of justdefault. This preserves the null-safe behavior ofinstanceof, which returns false for null, preventing NPE regressions in the generated code.Changes
buildSwitchTemplate()to emitcase null, defaultwhen no explicit null check existsTest Results
All existing tests pass with the updated expectations.