UVL - Universal Variability Language Java Feature Model Metamodel

This is a small default library used to manipulate UVL metamodels in JAVA. It uses the UVL-Grammar to parse the a given metamodel. If parsed the model can be modified in JAVA. It is possible to also convert the models to different levels.

How to use UVL can be found in this paper

✨ Key Features

• full support of UVL-Syntax (namespaces, feature hierarchies and constraints)
• convert between different language levels
• direct access to feature model components like features, groups and attributes

⚙️ Setup

To clone this repository with all submodules, use:

git clone --recurse-submodules https://github.com/Universal-Variability-Language/java-fm-metamodel.git

If you have already cloned the repository without submodules, you can initialize and update them afterwards with:

git submodule update --init --recursive

This ensures that all required submodules (e.g., test resources) are available and the project will build and test correctly

💡 Usage

📦 Getting Started

First, clone this repository to your local machine as explained in ⚙️ Setup. To use the Java-fm-metamodel, make sure you are in the project directory before running any further commands. Build the project with Maven:

mvn clean compile

This will compile all sources and ensure all dependencies (including submodules) are available.
Now you can execute code for manipulating UVL feature models as shown in the Examples below

🧩 Using as a Maven Dependency

You can also use the Java-fm-metamodel as a dependency in your own Maven project.
Add the following to your pom.xml:

<dependency>
  <groupId>io.github.universal-variability-language</groupId>
  <artifactId>fm-metamodel</artifactId>
  <version>1.1</version>
</dependency>

Make sure that the version matches the latest release.

---

Now you can use the classes from this library in your own Java code!

Examples

Some usage examples that show how to use the acquired UVLModel object can be found in src/main/java/de/vill/main/Example.java

Parsing

// First option:
UVLModelFactory uvlModelFactory = new UVLModelFactory();
FeatureModel featureModel = uvlModelFactory.parse(Paths.get("path/to/your/file.uvl"));

// Second option:
Path filePath = Paths.get(pathAsString);
String content = new String(Files.readAllBytes(filePath));
UVLModelFactory uvlModelFactory = new UVLModelFactory();
FeatureModel featureModel = uvlModelFactory.parse(content);

The class de.vill.main.UVLModelFactory exposes the static method parse(String) which will return an instance of a de.vill.model.FeatureModel class. If there is something wrong, a de.vill.exception.ParseError is thrown. The parser tries to parse the whole model, even if there are errors. If there are multiple errors, a de.vill.exception.ParseErrorList is returned which contains all errors that occurred.

Modifying

Feature feature = featureModel.getFeatureMap().get(featureName);
if (feature != null) {
  Attribute<?> attribute = feature.getAttributes().get(attributeName);
  if (attribute != null) {
    System.out.println("Name of the feature" + feature.getFeatureName());
    System.out.println("Name of the attribute" + attribute.getName());
  }
}

// Conversion
ConvertTypeLevel converter = new ConvertTypeLevel();
converter.convertFeatureModel(featureModel, convertedModel);

Writing into a file

// Write
String uvlModel = featureModel.toString();
Path filePath = Paths.get(featureModel.getNamespace() + ".uvl");
Files.write(filePath, uvlModel.getBytes());

A model can be printed with the toString() method of the de.vill.model.FeatureModel object.

🧪 Running Tests

The Java-fm-metamodel can be tested by running:

mvn test

📖 Citation

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}
}

Links

UVL models:

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

UVL parser:

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

Other parsers:

• https://github.com/Universal-Variability-Language/uvl-parser deprecated, Initial UVL Parser, based on Clojure and instaparse UVL-Parser
• https://github.com/diverso-lab/uvl-diverso/ Under development, Antlr4 Parser Diverso Lab

Usage of UVL:

• https://github.com/FeatureIDE/FeatureIDE Feature modelling tool
• https://github.com/SECPS/TraVarT Transformation Tool for Variability Artifacts