How to test cyclic dependencies with ArchUnit?

ArchUnit provides built-in syntax like 'slices().matching(...).should().beFreeOfCycles()' to automatically detect and forbid circular dependencies. You can integrate this into unit tests to catch issues early in development.

ArchUnit vs SonarQube for architecture validation?

ArchUnit is code-based and integrates with unit tests for immediate feedback during development, while SonarQube is a broader static analysis tool that runs separately and offers historical trends. ArchUnit is better for programmable, real-time enforcement.

Can ArchUnit be used with Spring Boot?

Yes, ArchUnit works well with Spring Boot. You can import classes from Spring packages and define rules to enforce layering, such as ensuring service layers don't depend on presentation layers, aligning with common Spring architectures.

What are best practices for writing ArchUnit tests?

Organize rules in logical groups, use descriptive names, and integrate them into CI/CD pipelines. Avoid overly restrictive rules that might hinder refactoring, and focus on critical architectural boundaries to maintain code quality.

How to create custom rules in ArchUnit?

Extend ArchUnit's base classes or use the fluent API to define custom conditions. The library's extensibility allows you to implement specific checks, such as validating naming conventions or dependency patterns, tailored to your project.

Does ArchUnit support Kotlin or other JVM languages?

ArchUnit analyzes bytecode, so it can work with Kotlin and other JVM languages, but support may be incomplete for language-specific features. It's primarily designed for Java, and complex Kotlin constructs might not be fully captured.

ArchUnit — Java Architecture Testing Library

What is ArchUnit?

ArchUnit is a Java library for specifying and asserting architectural rules in plain Java. It allows developers to define constraints on dependencies, layers, and slices within their codebase and automatically test them using standard unit testing frameworks. The library analyzes Java bytecode to ensure the code adheres to the intended design, preventing architectural drift and maintaining code quality.

Target Audience

Java developers and teams who need to enforce architectural consistency, prevent technical debt, and maintain clean code boundaries in medium to large-scale applications.

Value Proposition

Developers choose ArchUnit because it provides a simple, extensible, and framework-agnostic way to test architecture directly in Java, without relying on external tools or complex configurations. Its fluent API and seamless integration with existing test suites make it easy to adopt and maintain.

A Java architecture test library, to specify and assert architecture rules in plain Java

Use Cases

Best For

Enforcing layered architecture in enterprise Java applications
Preventing cyclic dependencies between modules or packages
Validating coding conventions and naming rules automatically
Ensuring that service layers do not depend on presentation layers
Maintaining architectural boundaries in microservices or modular monoliths
Integrating architecture tests into CI/CD pipelines

Not Ideal For

Projects using non-Java JVM languages like Kotlin or Scala, where bytecode analysis might not fully capture language-specific constructs
Teams that require real-time, IDE-integrated architecture feedback rather than post-compilation test execution
Applications where architectural rules are defined and managed through external configuration files or annotations, not code
Very small or prototype projects where the overhead of writing and maintaining architectural tests outweighs the benefits

Pros & Cons

Pros

Fluent Java API

Uses a plain Java fluent API to define rules, making them easy to write and understand without learning a new DSL, as demonstrated in the README's example code and GIF.

Seamless Test Integration

Integrates directly with JUnit and other testing frameworks, allowing architecture tests to run as part of the standard test suite, ensuring continuous validation during development.

Bytecode-Based Analysis

Analyzes Java bytecode to inspect the actual compiled structure, ensuring rules are enforced on the real code, not just source annotations or configurations.

Extensible for Custom Rules

The library is designed to be extensible, enabling developers to create custom architectural checks beyond built-in features, as highlighted in its philosophy of plain Java definitions.

Cons

Performance Overhead

Importing and analyzing bytecode for large codebases can significantly increase test execution time, especially in CI/CD pipelines, which may slow down feedback cycles.

Java-Centric Design

Primarily focused on Java; support for other JVM languages is limited and may not handle all language features correctly, potentially missing architectural issues in polyglot projects.

Verbose Rule Definition

Complex architectural rules can lead to lengthy and hard-to-maintain test code, requiring careful organization to avoid clutter and ensure readability over time.

What is ArchUnit?

Target Audience

Java developers and teams who need to enforce architectural consistency, prevent technical debt, and maintain clean code boundaries in medium to large-scale applications.

Value Proposition

Use Cases

Best For

Enforcing layered architecture in enterprise Java applications
Preventing cyclic dependencies between modules or packages
Validating coding conventions and naming rules automatically
Ensuring that service layers do not depend on presentation layers
Maintaining architectural boundaries in microservices or modular monoliths
Integrating architecture tests into CI/CD pipelines

Not Ideal For

Projects using non-Java JVM languages like Kotlin or Scala, where bytecode analysis might not fully capture language-specific constructs
Teams that require real-time, IDE-integrated architecture feedback rather than post-compilation test execution
Applications where architectural rules are defined and managed through external configuration files or annotations, not code
Very small or prototype projects where the overhead of writing and maintaining architectural tests outweighs the benefits

Pros & Cons

Pros

Fluent Java API

Uses a plain Java fluent API to define rules, making them easy to write and understand without learning a new DSL, as demonstrated in the README's example code and GIF.

Seamless Test Integration

Integrates directly with JUnit and other testing frameworks, allowing architecture tests to run as part of the standard test suite, ensuring continuous validation during development.

Bytecode-Based Analysis

Analyzes Java bytecode to inspect the actual compiled structure, ensuring rules are enforced on the real code, not just source annotations or configurations.

Extensible for Custom Rules

The library is designed to be extensible, enabling developers to create custom architectural checks beyond built-in features, as highlighted in its philosophy of plain Java definitions.

Cons

Performance Overhead

Importing and analyzing bytecode for large codebases can significantly increase test execution time, especially in CI/CD pipelines, which may slow down feedback cycles.

Java-Centric Design

Primarily focused on Java; support for other JVM languages is limited and may not handle all language features correctly, potentially missing architectural issues in polyglot projects.

Verbose Rule Definition

Complex architectural rules can lead to lengthy and hard-to-maintain test code, requiring careful organization to avoid clutter and ensure readability over time.

ArchUnit

What is ArchUnit?

Overview

Use Cases

Best For

Not Ideal For

Pros & Cons

Pros

Cons

Frequently Asked Questions

Found a gem we're missing?

ArchUnit

What is ArchUnit?

Overview

Use Cases

Best For

Not Ideal For

Pros & Cons

Pros

Cons

Frequently Asked Questions

Found a gem we're missing?