Gradle Build Language Reference

Version 4.0

Introduction

This reference guide describes the various types which make up the Gradle build language, or DSL.

Some basics

There are a few basic concepts that you should understand, which will help you write Gradle scripts.

First, Gradle scripts are configuration scripts. As the script executes, it configures an object of a particular type. For example, as a build script executes, it configures an object of type Project. This object is called the delegate object of the script. The following table shows the delegate for each type of Gradle script.

Type of script Delegates to instance of
Build script Project
Init script Gradle
Settings script Settings

The properties and methods of the delegate object are available for you to use in the script.

Second, each Gradle script implements the Script interface. This interface defines a number of properties and methods which you can use in the script.

Build script structure

A build script is made up of zero or more statements and script blocks. Statements can include method calls, property assignments, and local variable definitions. A script block is a method call which takes a closure as a parameter. The closure is treated as a configuration closure which configures some delegate object as it executes. The top level script blocks are listed below.

BlockDescription
allprojects { }

Configures this project and each of its sub-projects.

artifacts { }

Configures the published artifacts for this project.

buildscript { }

Configures the build script classpath for this project.

configurations { }

Configures the dependency configurations for this project.

dependencies { }

Configures the dependencies for this project.

repositories { }

Configures the repositories for this project.

sourceSets { }

Configures the source sets of this project.

subprojects { }

Configures the sub-projects of this project.

publishing { }

Configures the PublishingExtension added by the publishing plugin.

A build script is also a Groovy script, and so can contain those elements allowed in a Groovy script, such as method definitions and class definitions.

Core types

Listed below are some of the central types which are used in Gradle scripts:

TypeDescription
Project

This interface is the main API you use to interact with Gradle from your build file. From a Project, you have programmatic access to all of Gradle's features.

Task

A Task represents a single atomic piece of work for a build, such as compiling classes or generating javadoc.

Gradle

Represents an invocation of Gradle.

Settings

Declares the configuration required to instantiate and configure the hierarchy of Project instances which are to participate in a build.

IncludedBuild

A build that is included in the composite.

Script

This interface is implemented by all Gradle scripts to add in some Gradle-specific methods. As your compiled script class will implement this interface, you can use the methods and properties declared by this interface directly in your script.

JavaToolChain

A set of tools for building from Java source.

SourceSet

A SourceSet represents a logical group of Java source and resources.

SourceSetOutput

A collection of all output directories (compiled classes, processed resources, etc.) - notice that SourceSetOutput extends FileCollection.

SourceDirectorySet

A SourceDirectorySet represents a set of source files composed from a set of source directories, along with associated include and exclude patterns.

IncrementalTaskInputs

Provides access to any input files that need to be processed by an incremental task.

Configuration

A Configuration represents a group of artifacts and their dependencies. Find more information about declaring dependencies to a configuration or about managing configurations in docs for ConfigurationContainer

ResolutionStrategy

Defines the strategies around dependency resolution. For example, forcing certain dependency versions, substitutions, conflict resolutions or snapshot timeouts.

ArtifactResolutionQuery

A builder to construct a query that can resolve selected software artifacts of the specified components.

ComponentSelection

Represents a tuple of the component selector of a module and a candidate version to be evaluated in a component selection rule.

ComponentSelectionRules

Represents a container for component selection rules. Rules can be applied as part of the resolutionStrategy of a configuration and individual components can be explicitly accepted or rejected by rule. Components that are neither accepted or rejected will be subject to the default version matching strategies.

ConventionProperty

ConventionProperty can be assigned but cannot be mutated (even if the object is mutable!)

GradlePluginPortal

The Gradle Plugin Portal which can be used to resolve plugins.

ExtensionAware

Objects that can be extended at runtime with other objects.

ExtraPropertiesExtension

Additional, ad-hoc, properties for Gradle domain objects.

PublishingExtension

The configuration of how to “publish” the different components of a project.

IvyPublication

A IvyPublication is the representation/configuration of how Gradle should publish something in Ivy format, to an Ivy repository. You directly add a named Ivy Publication the project's publishing.publications container by providing IvyPublication as the type.

IvyArtifact

An artifact published as part of a IvyPublication.

IvyArtifactSet

A Collection of IvyArtifacts to be included in an IvyPublication. Being a DomainObjectSet, a IvyArtifactSet provides convenient methods for querying, filtering, and applying actions to the set of IvyArtifacts.

IvyModuleDescriptorSpec

The descriptor of any Ivy publication.

IvyPluginRepository

Represents an Ivy repository which contains Gradle plugins.

MavenPublication

A MavenPublication is the representation/configuration of how Gradle should publish something in Maven format. You directly add a named Maven Publication the project's publishing.publications container by providing MavenPublication as the type.

MavenArtifact

An artifact published as part of a MavenPublication.

MavenArtifactSet

A Collection of MavenArtifacts to be included in a MavenPublication. Being a DomainObjectSet, a MavenArtifactSet provides convenient methods for querying, filtering, and applying actions to the set of MavenArtifacts.

MavenPom

The POM for a Maven publication. The MavenPom.withXml(org.gradle.api.Action) method can be used to modify the descriptor after it has been generated according to the publication data.

MavenPluginRepository

Represents a Maven repository which contains Gradle plugins.

PluginDependenciesSpec

The DSL for declaring plugins to use in a script.

PluginDependencySpec

A mutable specification of a dependency on a plugin.

PluginManagementSpec

Configures how plugins are resolved.

PluginRepositoriesSpec

Used to declare PluginRepository instances.

PluginRepository

Represents a repository from which Gradle plugins can be resolved.

ResourceHandler

Provides access to resource-specific utility methods, for example factory methods that create various resources.

TextResourceFactory

Creates TextResources backed by sources such as strings, files, and archive entries.

Container types

Container types that handle various declarative elements (e.g. dependencies, configurations, artifacts, etc.):

TypeDescription
ConfigurationContainer

A ConfigurationContainer is responsible for declaring and managing configurations. See also Configuration.

RepositoryHandler

A RepositoryHandler manages a set of repositories, allowing repositories to be defined and queried.

DependencyHandler

A DependencyHandler is used to declare dependencies. Dependencies are grouped into configurations (see Configuration).

ArtifactHandler

This class is for defining artifacts to be published and adding them to configurations. Creating publish artifacts does not mean to create an archive. What is created is a domain object which represents a file to be published and information on how it should be published (e.g. the name).

Build Cache types

Types used to connect to and configure the build cache:

TypeDescription
BuildCacheConfiguration

Configuration for the build cache for an entire Gradle build.

DirectoryBuildCache

Configuration object for the local directory build cache.

HttpBuildCache

Configuration object for the HTTP build cache. The build cache only supports BASIC authentication currently.

Input Normalization types

Types used to configure input normalization

TypeDescription
InputNormalizationHandler

Used to configure input normalization. Currently, it is only possible to configure runtime classpath normalization.

InputNormalization

Input normalization configuration. Input normalization is used when Gradle tries to determine if two task inputs are different. Gradle normalizes both inputs and the inputs are considered different if and only if the normalizations are different.

RuntimeClasspathNormalization

Configuration of runtime classpath normalization.

Help Task types

Below are the task types that are available for every Gradle project. Those task types can also be declared and configured directly in the build script.

TypeDescription
TaskReportTask

Displays a list of tasks in the project. An instance of this type is used when you execute the tasks task from the command-line.

ProjectReportTask

Displays a list of projects in the build. An instance of this type is used when you execute the projects task from the command-line.

DependencyReportTask

Displays the dependency tree for a project. An instance of this type is used when you execute the dependencies task from the command-line.

DependencyInsightReportTask

Generates a report that attempts to answer questions like:

PropertyReportTask

Displays the properties of a project. An instance of this type is used when you execute the properties task from the command-line.

ComponentReport

Displays some details about the software components produced by the project.

DependentComponentsReport

Displays dependent components.

ModelReport

Displays some details about the configuration model of the project. An instance of this type is used when you execute the model task from the command-line.

Task types

Listed below are the various task types which are available for use in your build script:

TypeDescription
AntlrTask

Generates parsers from Antlr grammars.

BuildEnvironmentReportTask

Provides information about the build environment for the project that the task is associated with.

Checkstyle

Runs Checkstyle against some source files.

CodeNarc

Runs CodeNarc against some source files.

CompareGradleBuilds

Executes two Gradle builds (that can be the same build) with specified versions and compares the outcomes. Please see the “Comparing Builds” chapter of the Gradle User Guide for more information.

Copy

Copies files into a destination directory. This task can also rename and filter files as it copies. The task implements CopySpec for specifying what to copy.

CreateStartScripts

Creates start scripts for launching JVM applications.

Delete

Deletes files or directories. Example:

Ear

Assembles an EAR archive.

Exec

Executes a command line process. Example:

FindBugs

Analyzes code with FindBugs. See the FindBugs Manual for additional information on configuration options.

GenerateIvyDescriptor

Generates an Ivy XML Module Descriptor file.

GenerateMavenPom

Generates a Maven module descriptor (POM) file.

GenerateBuildDashboard

Generates build dashboard report.

GradleBuild

Executes a Gradle build.

GroovyCompile

Compiles Groovy source files, and optionally, Java source files.

Groovydoc

Generates HTML API documentation for Groovy source, and optionally, Java source.

HtmlDependencyReportTask

Generates an HTML dependency report. This report combines the features of the ASCII dependency report and those of the ASCII dependency insight report. For a given project, it generates a tree of the dependencies of every configuration, and each dependency can be clicked to show the insight of this dependency.

JacocoReport

Task to generate HTML, Xml and CSV reports of Jacoco coverage data.

JacocoMerge

Task to merge multiple execution data files into one.

JacocoCoverageVerification

Task for verifying code coverage metrics. Fails the task if violations are detected based on specified rules.

Jar

Assembles a JAR archive.

JavaCompile

Compiles Java source files.

Javadoc

Generates HTML API documentation for Java classes.

JavaExec

Executes a Java application in a child process.

JDepend

Analyzes code with JDepend.

Pmd

Runs a set of static code analysis rules on Java source code files and generates a report of problems found.

PublishToIvyRepository

Publishes an IvyPublication to an IvyArtifactRepository.

PublishToMavenRepository

Publishes a MavenPublication to a MavenArtifactRepository.

ScalaCompile

Compiles Scala source files, and optionally, Java source files.

ScalaDoc

Generates HTML API documentation for Scala source files.

InitBuild

Generates a Gradle project structure.

Sign

A task for creating digital signature files for one or more; tasks, files, publishable artifacts or configurations.

Sync

Synchronizes the contents of a destination directory with some source directories and files.

Tar

Assembles a TAR archive.

Test

Executes JUnit (3.8.x or 4.x) or TestNG tests. Test are always run in (one or more) separate JVMs. The sample below shows various configuration options.

TestReport

Generates an HTML test report from the results of one or more Test tasks.

Upload

Uploads the artifacts of a Configuration to a set of repositories.

War

Assembles a WAR archive.

Wrapper

Generates scripts (for *nix and windows) which allow you to build your project with Gradle, without having to install Gradle.

WriteProperties

Writes a Properties in a way that the results can be expected to be reproducible.

Zip

Assembles a ZIP archive. The default is to compress the contents of the zip.

Reporting types

Listed below are some of the types which are used when generating reports:

TypeDescription
CustomizableHtmlReport

A HTML Report whose generation can be customized with a XSLT stylesheet.

SingleFileReport

A report that is a single file.

DirectoryReport

A directory based report to be created.

FindBugsXmlReport

The single file XML report for FindBugs.

Report

A file based report to be created.

Reporting

An object that provides reporting options.

ReportContainer

A container of Report objects, that represent potential reports.

ReportingExtension

A project extension named "reporting" that provides basic reporting settings and utilities.

Eclipse/IDEA model types

Used to configure Eclipse or IDEA plugins

TypeDescription
EclipseModel

DSL-friendly model of the Eclipse project information. First point of entry for customizing Eclipse project generation.

EclipseProject

Enables fine-tuning project details (.project file) of the Eclipse plugin

EclipseClasspath

The build path settings for the generated Eclipse project. Used by the GenerateEclipseClasspath task to generate an Eclipse .classpath file.

EclipseJdt

Enables fine-tuning jdt details of the Eclipse plugin

EclipseWtp

Enables fine-tuning wtp/wst details of the Eclipse plugin

EclipseWtpComponent

Enables fine-tuning wtp component details of the Eclipse plugin

EclipseWtpFacet

Enables fine-tuning wtp facet details of the Eclipse plugin

IdeaModel

DSL-friendly model of the IDEA project information. First point of entry when it comes to customizing the IDEA generation.

IdeaProject

Enables fine-tuning project details (*.ipr file) of the IDEA plugin.

IdeaModule

Enables fine-tuning module details (*.iml file) of the IDEA plugin.

IdeaWorkspace

Enables fine-tuning workspace details (*.iws file) of the IDEA plugin.

XmlFileContentMerger

Models the generation/parsing/merging capabilities. Adds XML-related hooks.

FileContentMerger

Models the generation/parsing/merging capabilities.

Eclipse/IDEA task types

Tasks contributed by IDE plugins. To configure IDE plugins please use IDE model types.

TypeDescription
GenerateEclipseProject

Generates an Eclipse .project file. If you want to fine tune the eclipse configuration

GenerateEclipseClasspath

Generates an Eclipse .classpath file. If you want to fine tune the eclipse configuration

GenerateEclipseJdt

Generates the Eclipse JDT configuration file. If you want to fine tune the eclipse configuration

GenerateEclipseWtpComponent

Generates the org.eclipse.wst.common.component settings file for Eclipse WTP. If you want to fine tune the eclipse configuration

GenerateEclipseWtpFacet

Generates the org.eclipse.wst.common.project.facet.core settings file for Eclipse WTP. If you want to fine tune the eclipse configuration

GenerateIdeaModule

Generates an IDEA module file. If you want to fine tune the idea configuration

GenerateIdeaProject

Generates an IDEA project file for root project *only*. If you want to fine tune the idea configuration

GenerateIdeaWorkspace

Generates an IDEA workspace file *only* for root project. There's little you can configure about workspace generation at the moment.

Native software model types

Used to configure software components developed with native code.

TypeDescription
PrebuiltLibrary

A library component that is not built by gradle.

PrebuiltSharedLibraryBinary

A shared library that exists at a known location on the filesystem.

PrebuiltStaticLibraryBinary

A static library that exists at a known location on the filesystem.

NativeComponentSpec

Definition of a software component that is to be built by Gradle to run a on JVM platform.

NativeExecutableSpec

Definition of a native executable component that is to be built by Gradle.

NativeLibrarySpec

Definition of a native library component that is to be built by Gradle.

NativeTestSuiteSpec

A component representing a suite of tests that will be executed together.

CUnitTestSuiteSpec

Test suite of CUnit tests.

GoogleTestTestSuiteSpec

Test suite of Google Test tests.

NativeBinarySpec

Represents a binary artifact that is the result of building a native component.

NativeExecutableBinarySpec

An binary built by Gradle for a native application.

NativeLibraryBinarySpec

Represents a binary artifact that is the result of building a native library component.

SharedLibraryBinarySpec

A shared library binary built by Gradle for a native library.

StaticLibraryBinarySpec

A static library binary built by Gradle for a native library.

NativeTestSuiteBinarySpec

An executable which runs a suite of tests.

CUnitTestSuiteBinarySpec

An executable which run a CUnit test suite.

GoogleTestTestSuiteBinarySpec

An executable which run a Google Test test suite.

NativePlatform

A target platform for building native binaries. Each target platform is given a name, and may optionally be given a specific Architecture and/or OperatingSystem to target.

BuildType

Specifies a build-type for a native binary. Common build types are 'debug' and 'release', but others may be defined.

Flavor

Defines a custom variant that differentiate a NativeBinary.

Gcc

The GNU GCC tool chain.

Clang

The Clang tool chain.

VisualCpp

The Visual C++ tool chain.

AssemblerSourceSet

A set of assembly language sources.

CSourceSet

A set of C source files.

CppSourceSet

A set of C++ source files.

ObjectiveCSourceSet

A set of Objective-C source files.

ObjectiveCppSourceSet

A set of Objective-C++ source files.

WindowsResourceSet

A set of Windows Resource definition files.

VisualStudioProject

A visual studio project, created from one or more NativeBinary instances.

VisualStudioSolution

A visual studio solution, representing one or more NativeBinarySpec instances from the same NativeComponentSpec.

NativeExecutable

An executable native component that is built by Gradle.

NativeLibrary

A library component that is built by a gradle project.

NativeBinary

Represents a particular binary artifact.

NativeExecutableBinary

A binary artifact for a NativeExecutable, targeted at a particular platform with specific configuration.

SharedLibraryBinary

A NativeLibrary that has been compiled and linked as a shared library.

StaticLibraryBinary

A NativeLibrary that has been compiled and archived into a static library.

Native binary task types

Tasks used to build native binaries.

TypeDescription
CppCompile

Compiles C++ source files into object files.

CCompile

Compiles C source files into object files.

Assemble

Translates Assembly language source files into object files.

ObjectiveCCompile

Compiles Objective-C source files into object files.

ObjectiveCppCompile

Compiles Objective-C++ source files into object files.

WindowsResourceCompile

Compiles Windows Resource scripts into .res files.

LinkExecutable

Links a binary executable from object files and libraries.

LinkSharedLibrary

Links a binary shared library from object files and imported libraries.

CreateStaticLibrary

Assembles a static library from object files.

InstallExecutable

Installs an executable with it's dependent libraries so it can be easily executed.

RunTestExecutable

Runs a compiled and installed test executable.