Implement Parallel Method Execution in JUnit-Vintage engine

[YongGoose]

Description

JUnit 4 allows running methods in parallel by setting a RunnerScheduler for ParentRunner subclasses.
This issue aim to implement this feature to improve test execution performance.

Objectives

• Implement parallel execution of test methods
• Adjust existing tests to verify method parallelization

Deliverables

• Implement custom RunnerScheduler using ExecutorService
• Update tests to verify parallel method execution
• Document usage and performance implications

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This issue is a follow-up task to the issue below.

• Support some level of parallelization in junit-vintage-engine #2229

[YongGoose]

@marcphilipp

I plan to add a property to the JUnit-Vintage engine, similar to the two property values in the JUnit-Jupiter engine, to select whether only classes should be run in parallel or only methods should be run in parallel.

• junit.jupiter.execution.parallel.mode.default
• junit.jupiter.execution.parallel.mode.classes.default

plan to implement it similar to JUnit4's ParallelComputer

• https://github.com/junit-team/junit4/blob/df00d5eced3a7737b88de0f6f9e3673f0cf88f88/src/main/java/org/junit/experimental/ParallelComputer.java#L15-L17

I will complete the implementation by tomorrow and create a PR.
If you have any better suggestions, please let me know in the comments! 😁

[marcphilipp]

I think we should have two independent configuration parameters: one for classes and one for methods.

• junit.vintage.execution.parallel.classes
• junit.vintage.execution.parallel.methods

[YongGoose]

I think we should have two independent configuration parameters: one for classes and one for methods.

• junit.vintage.execution.parallel.classes
• junit.vintage.execution.parallel.methods

Thank you for the suggestion 👍🏻

I’ll implement the two configuration parameters as you suggested :D