Gradle is an open-source build automation tool that combines the best features of Apache Ant and Apache Maven to manage the entire software lifecycle, from compilation and packaging to testing and deployment. It was first released in 2008 and was adopted by Google in 2013 as the official build system for Android projects.

Major features

  • Domain-specific language (DSL): Instead of using verbose XML files like Ant and Maven, Gradle uses a concise and expressive DSL based on Groovy or Kotlin. This makes build scripts much more readable, maintainable, and easier to write.
  • Directed acyclic graph (DAG): Gradle uses a DAG to model its builds. This means the build is executed as a series of tasks, and the dependencies between tasks define the execution order. This allows for highly flexible and customizable build logic.
  • High performance: Gradle is significantly faster than both Ant and Maven, especially for large, multi-module projects. Its performance features include:
    • Incremental builds: Gradle tracks the inputs and outputs of tasks and only re-executes tasks when their inputs change. This avoids redundant work and drastically reduces build times.
    • Build cache: It can reuse the outputs of tasks from a previous build, either on the same machine or from a shared cache, further accelerating builds.
    • Gradle daemon: A long-lived process that keeps build information in memory, reducing startup overhead for subsequent builds.
  • Dependency management: Like Maven, Gradle provides robust dependency management to fetch and cache third-party libraries from repositories like Maven Central. It offers advanced dependency conflict resolution and supports custom dependency scopes.
  • Convention-over-configuration: Gradle provides a flexible “convention-over-configuration” approach, borrowing the structured project layout from Maven. This makes simple projects easy to configure while still allowing for extensive customization when needed.
  • Multi-project support: Designed to support large, multi-project builds, Gradle makes it simple to manage complex project structures. Its composite builds feature allows for combining different projects and builds.
  • Extensibility: Gradle’s plugin system allows developers to extend its functionality easily. Plugins can be written directly in the build script or packaged for reuse, making it modular and adaptable to new features and languages.
  • Polyglot support: While most popular in the Java ecosystem (for Java, Kotlin, and Android), Gradle can be extended to support many other languages and platforms, including C/C++ and JavaScript.

Comparison with Maven and Ant

Feature Gradle Maven Ant
Build Configuration Uses a concise, expressive DSL based on Groovy or Kotlin, which is code-based and programmatic. Uses a fixed, XML-based Project Object Model (POM) that is declarative and rigid. Uses XML for scripting, which is highly flexible but also verbose and requires more boilerplate code.
Flexibility Highly flexible and customizable due to its programmatic DSL and task-based model. It’s built for complex and custom build logic. Relies on a standardized lifecycle and project structure, which offers stability but limits customization without creating plugins. Extremely flexible and can perform any task, but lacks convention, so every project can be different and difficult to manage.
Performance The fastest of the three due to its use of incremental builds, a build cache, and the Gradle daemon. Slower than Gradle, especially for incremental builds, as it re-executes more tasks by default. Older and generally the slowest for large projects, as it must execute every step of the build process.
Dependency Management Robust dependency management, including advanced features like customizable conflict resolution and api vs. implementation dependencies. Offers solid dependency management through Maven Central, but its conflict resolution is simpler and can be less reliable. Does not natively support dependency management and requires a separate tool like Apache Ivy.
Project Model Builds a task graph that allows for complex, directed dependency logic. Uses a fixed, linear model of phases and goals. Uses a target-based model with implicit dependencies.
Ecosystem A modern, growing community, especially strong in the Android ecosystem. A large, mature ecosystem with a vast library of available plugins. The oldest of the three, now with a smaller, declining community.