ClassTrim

ClassTrim is a framework to recommend move method refactoring using Non-dominated Sorting Genetic Algorithm-III ( NSGA-III) to minimizing the number of classes that exceed predefined metric thresholds.

Raw experiment data doi: 10.17632/8b3fd45kp6.1

Demo

Run ClassTrim plugin on smelly-demo

Quick start

1. Prerequisites

• JDK 17+
• Maven 3.8+

2. Configure environment

• Copy classtrim-core/src/main/resources/config.properties.example to classtrim-core/src/main/resources/config.properties.
• Edit the new config.properties and set values for your environment:
  • mavenRepo: absolute path to your local Maven repository
  • datasetRoot: absolute path to the datasets root folder
  • outputFolder: output folder for results (optional; default output)
  • projectCacheFolder: folder for serialized project cache (optional; default .project)
  • notifyUrl: optional webhook for notifications

3. Entry point

   • org.classtrim.Main run the move method refactoring algorithm on each project.
   • org.classtrim.NSGAII, org.classtrim.NSGAIII, or org.classtrim.MOEAD run it once.
   • org.classtrim.baseline.BaselineRefactor run baseline comparison experiment.

4. Build and test modules

• Run all modules: mvn test
• Run core only: mvn -pl classtrim-core test
• Run CLI only: mvn -pl classtrim-cli test

5. Build IntelliJ plugin

• Package plugin zip: mvn -pl classtrim-plugin -am package
• Output: classtrim-plugin/target/classtrim-plugin-1.0-SNAPSHOT-idea-plugin.zip

Module extraction (in progress)

This repository now includes extraction scaffolding for library-style usage:

• classtrim-core/: Maven module packaging the current core code and new injectable APIs under org.classtrim.core.*
• classtrim-cli/: Maven module with org.classtrim.cli.RunNsgaiii example entrypoint using the extracted service API
• classtrim-plugin/: IntelliJ IDEA plugin scaffold wired to run core analysis and show notifications

New core API entrypoints:

• org.classtrim.core.analyzer.ProjectAnalyzer / StandardProjectAnalyzer
• org.classtrim.core.engine.RefactoringEngine / NSGAIIIRefactoringEngine
• org.classtrim.core.service.ClassTrimService
• org.classtrim.core.model.ProjectSource / BinaryPathProjectSource
• org.classtrim.core.repository.ProjectRepository (in-memory and filesystem implementations)

How I calculate metrics and some common question are in wiki.

Baseline comparison (baseline/)

This folder contains results from baseline tools for comparison, including:

• Runtime screenshots produced during baseline runs
• Suggested outputs generated by each baseline tool (e.g., *.tsv summaries)

Typical subfolders include JDeodorant/, JMove/, HMove/ and REsolution/, each organized by project-version. These provide reference suggestions and artifacts to compare against this project's NSGA-based refactoring outputs.

Code features

1. Follow unix philosophy.
2. Uses Lombok to simplify data classes (getters/setters, constructors)
3. Uses Java 8 Optional to handle nulls elegantly
4. Emphasizes immutability; returns unmodified collections
5. Caches computed objects to improve performance
6. Keeps dependencies minimal
7. Automatically records experiment results and summaries (summary may be improved by using a database)
8. Includes unit tests

Thanks

• ASM
• JMetal

License

MIT