feat: Add distribution detection support to .sdkmanrc file

[lukaszgyg]

Summary

Extends the existing .sdkmanrc support to automatically detect and use the Java distribution identifier from SDKMAN version strings (for example, java=21.0.5-tem).

Related Issue

#971

Changes

• Enhanced .sdkmanrc parsing to extract both the version and the distribution identifier
• Added SDKMAN distribution identifier mapping to setup-java distribution names, including:
  • tem -> temurin
  • sem -> semeru
  • albba/dragonwell -> dragonwell
  • zulu -> zulu
  • amzn -> corretto
  • graal/graalce -> graalvm
  • librca -> liberica
  • ms -> microsoft
  • oracle -> oracle
  • sapmchn -> sapmachine
  • jbr -> jetbrains
• Made distribution input optional when .sdkmanrc includes a supported distribution suffix
• Added unit coverage for supported SDKMAN identifiers, unknown identifiers, and missing suffixes
• Regenerated dist after the source changes

Usage

Before (distribution required):

- uses: actions/setup-java@main
  with:
    distribution: temurin
    java-version-file: .sdkmanrc

After (distribution auto-detected):

- uses: actions/setup-java@main
  with:
    java-version-file: .sdkmanrc

.sdkmanrc file:

java=21.0.5-tem

Backward Compatibility

• Fully backward compatible with existing configurations
• When .sdkmanrc does not include a supported distribution suffix, the distribution input is still required
• Existing workflows without distribution suffix continue to work unchanged

Testing

• npm run format-check
• npm run lint
• npm run build
• npm test -- --runInBand __tests__/util.test.ts
• npm test locally; all suites passed except one unrelated JetBrains network lookup failure in __tests__/distributors/jetbrains-installer.test.ts

[Copilot]

Pull request overview

This PR extends .sdkmanrc file support to automatically detect and use Java distribution identifiers from SDKMAN version strings (e.g., java=21.0.5-tem), making the distribution input optional when a distribution suffix is present.

Changes:

• Enhanced .sdkmanrc parsing to extract both version and distribution identifier
• Added SDKMAN-to-setup-java distribution mapping for 10 distributions (Temurin, Zulu, Corretto, GraalVM, Liberica, Microsoft, Oracle, SapMachine, JetBrains, Dragonwell)
• Made distribution input optional in action.yml when distribution can be detected from file
• Updated return type of getVersionFromFileContent from string to VersionInfo object containing version and optional distribution
• Modified setup logic to prefer file-extracted distribution over input parameter

Reviewed changes

Copilot reviewed 6 out of 9 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/util.ts	Added VersionInfo interface, updated getVersionFromFileContent to return version and distribution, added mapSdkmanDistribution function with SDKMAN identifier mappings
src/setup-java.ts	Modified to handle optional distribution input, prioritize file-extracted distribution, refactored installation logic
action.yml	Updated distribution input to be optional with clarified description
tests/util.test.ts	Updated test assertions to match new VersionInfo return type, added tests for various distribution identifiers
.sdkmanrc.example	Added example file demonstrating supported SDKMAN distribution identifiers
.github/workflows/sdkmanrc-example.yml	Added workflow examples showing usage with and without distribution suffix
dist/setup/index.js	Compiled source changes for setup entry point
dist/cleanup/index.js	Compiled source changes for cleanup entry point
package-lock.json	Updated peer dependency flags (normal npm behavior)

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[bschulz-nf]

would be great if someone could review this PR. Having to specify the JDK vendor twice is actually improvable.

At the moment users have to specify the JDK vendor e.g. Temurin in the sdkman.rc file like "25.0.1-tem" so sdkman picks up the Temurin JDK and also explicitly add a distribution entry containing "temurin" in the github action as well.

[lukaszgyg]

Addressed the review feedback and updated the PR description. The branch now includes sem -> semeru, albba -> dragonwell, additional SDKMAN coverage, and regenerated dist. Ready for another look.