feat: Add comprehensive Gradle build tool support for Java

[HeshamHM28]

Summary

Adds full Gradle support to CodeFlash Java implementation, enabling optimization of Gradle-based Java projects alongside existing Maven support.

Changes

Core Gradle Implementation (build_tools.py)

• GradleTestResult dataclass for test execution results
• run_gradle_tests() function with support for:
  • Running all tests or specific test classes/methods using --tests flag
  • Multi-module Gradle projects via task prefixing (e.g., :server:test)
  • JaCoCo coverage collection with XML reports
  • Gradle wrapper (gradlew) detection with fallback to system gradle
  • Environment variable passing and timeout handling
• compile_with_gradle() for compiling main and test sources
• _parse_gradle_test_results() for parsing JUnit XML output from Gradle test runs
• Updated find_gradle_executable() to accept project_root parameter for wrapper detection
• Updated detect_build_tool() to handle both Path and string inputs

Multi-Module Support (test_runner.py)

• Extended _find_multi_module_root() to detect Gradle multi-module projects:
  • Parse settings.gradle and settings.gradle.kts files
  • Extract module names from include statements
  • Support both Groovy DSL and Kotlin DSL syntax
  • Search parent directories for multi-module roots
• Created build tool dispatcher in _run_maven_tests() to route to Gradle or Maven
• Implemented _run_gradle_tests_impl() for Gradle-specific test execution
• Converted Maven test filter format to Gradle --tests format

Test Coverage

Added comprehensive test suite with 21 tests in test_gradle_support.py:

• Test execution (all tests, specific classes, specific methods)
• Multi-module project support
• Compilation (main + test sources)
• Error handling and timeout scenarios
• JaCoCo coverage integration
• XML result parsing

All tests passing: 21/21 ✅

Testing

Unit Tests

uv run pytest tests/test_languages/test_java/test_gradle_support.py -v

Integration Testing (Elasticsearch)

Tested on Elasticsearch repository (multi-module Gradle project):

• Build tool detection works correctly
• Multi-module root detection works correctly
• Test generation works correctly

Note: There is a separate issue with project_root detection in CodeFlash CLI that affects test execution. This is not a bug in the Gradle support code itself, but rather in how CodeFlash determines the project root from command-line arguments.

Backwards Compatibility

This PR maintains full backwards compatibility:

• Existing Maven projects continue to work unchanged
• Build tool detection automatically selects correct tool
• No breaking changes to APIs or interfaces

Implementation Notes

Gradle Test Filtering

Gradle uses a different test filtering syntax than Maven:

• Maven: com.example.TestClass#testMethod
• Gradle: --tests com.example.TestClass.testMethod

The implementation converts between these formats automatically.

Multi-Module Support

For multi-module projects, the implementation:

1. Detects the root settings.gradle file
2. Parses module definitions
3. Determines which module contains the test
4. Executes tests with module-specific tasks (:module:test)

Coverage Collection

JaCoCo integration for Gradle:

• Uses test jacocoTestReport tasks
• Configures XML report generation
• Locates reports at build/reports/jacoco/test/jacocoTestReport.xml

🤖 Generated with Claude Code

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

---

Ubuntu seems not to be a GitHub user. You need a GitHub account to be able to sign the CLA. If you have already a GitHub account, please add the email address used for this commit to your account.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[codeflash-ai]

⚡️ Codeflash found optimizations for this PR

📄 19% (0.19x) speedup for _validate_test_filter in codeflash/languages/java/test_runner.py

⏱️ Runtime : 794 microseconds → 666 microseconds (best of 105 runs)

A dependent PR with the suggested changes has been created. Please review:

• ⚡️ Speed up function _validate_test_filter by 19% in PR #1319 (feat/java-gradle-support) #1358

If you approve, it will be merged into this PR (branch feat/java-gradle-support).