UVL (Universal Variability Language) is a concise and extensible language for modeling variability in software product lines. It supports multiple programming languages and provides a grammar-based foundation for building tools and parsers.

This repository contains the ANTLR4 grammar files for UVL. With these, you can generate parsers for UVL tailored to specific programming languages like Java, JavaScript, and Python.

• Language-level modularity
• Namespaces and imports
• Feature trees with attributes and cardinalities
• Cross-tree constraints
• Extensible for different target languages

• uvl/UVLParser.g4 – Base grammar in EBNF form
• uvl/UVLLexer.g4 – Base lexer grammar for UVL
• uvl/Java/UVLJava*.g4, uvl/Python/UVLPython*.g4, etc. – Language-specific grammar files
• java/ – Java-based parser implementation using Maven
• python/ – Python-based parser implementation
• javascript/ – JavaScript-based parser implementation
• tests/ – UVL test cases for validation

UVL uses ANTLR4 as its parser generator.

Each UVL model may consist of five optional sections:

1. Language levels: Enable optional concepts via include keyword.
2. Namespace: Allows referencing the model from other UVL models.
3. Imports: Include other feature models (e.g., subdir.filename as fn).
4. Feature tree: Hierarchical features with cardinalities, attributes, and group types (mandatory, optional, or, alternative).
5. Cross-tree constraints: Logical and arithmetic constraints among features.

namespace Server

features
  Server {abstract}
    mandatory
      FileSystem
        or
          NTFS
          APFS
          EXT4
      OperatingSystem {abstract}
        alternative
          Windows
          macOS
          Debian
    optional
      Logging {
        default,
        log_level "warn"
      }

constraints
  Windows => NTFS
  macOS => APFS

Explanation:

• Server is an abstract feature.
• It must include a FileSystem and an OperatingSystem.
• Logging is optional and includes an attribute.
• Logical constraints define dependencies between features.

🔗 More examples: https://github.com/Universal-Variability-Language/uvl-models/tree/main/Feature_Models

To use UVL in your projects, you can either:

1. Use the pre-built parsers

   Java Parser

   Include the following dependency in your Maven project:

   <dependency>
       <groupId>io.github.universal-variability-language</groupId>
       <artifactId>uvl-parser</artifactId>
       <version>0.3</version>
   </dependency>

   Python Parser

   Install the package via pip:

   pip install uvlparser

   JavaScript Parser

   Install the package via npm:

   npm install uvl-parser

2. Build the parser manually See the sections below for details.

• ANTLR4
• Java 17+
• Maven

1. Clone the repository:

 git clone https://github.com/Universal-Variability-Language/uvl-parser

2. Build the parser:

 cd java
 mvn clean package

3. Include the generated JAR in your Java project.

UVL Models & Tools

• https://github.com/Universal-Variability-Language/uvl-models
• https://www.uvlhub.io/

Tooling Ecosystem

• https://github.com/FeatureIDE/FeatureIDE
• https://ide.flamapy.org/
• https://github.com/Universal-Variability-Language/uvl-lsp
• https://github.com/SECPS/TraVarT
• https://github.com/AlexCortinas/spl-js-engine

If you use UVL in your research, please cite:

@article{UVL2024,
  title     = {UVL: Feature modelling with the Universal Variability Language},
  journal   = {Journal of Systems and Software},
  volume    = {225},
  pages     = {112326},
  year      = {2025},
  issn      = {0164-1212},
  doi       = {https://doi.org/10.1016/j.jss.2024.112326},
  url       = {https://www.sciencedirect.com/science/article/pii/S0164121224003704},
  author    = {David Benavides and Chico Sundermann and Kevin Feichtinger and José A. Galindo and Rick Rabiser and Thomas Thüm},
  keywords  = {Feature model, Software product lines, Variability}
}

Feel free to open issues or pull requests if you have suggestions or improvements. For questions or collaboration inquiries, visit the UVL Website: https://universal-variability-language.github.io/