Interface DependencyHandler

All Superinterfaces:
ExtensionAware
public interface DependencyHandler extends ExtensionAware

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

To declare a specific dependency for a configuration you can use the following syntax:

dependencies {
    configurationName dependencyNotation
}

Example shows a basic way of declaring dependencies. 

apply plugin: 'java'
//so that we can use 'implementation', 'testImplementation' for dependencies

dependencies {
  //for dependencies found in artifact repositories you can use
  //the group:name:version notation
  implementation 'commons-lang:commons-lang:2.6'
  testImplementation 'org.mockito:mockito:1.9.0-rc1'

  //map-style notation:
  implementation group: 'com.google.code.guice', name: 'guice', version: '1.0'

  //declaring arbitrary files as dependencies
  implementation files('hibernate.jar', 'libs/spring.jar')

  //putting all jars from 'libs' onto compile classpath
  implementation fileTree('libs')
}

Advanced dependency configuration

To do some advanced configuration on a dependency when it is declared, you can additionally pass a configuration closure:

dependencies {
    configurationName(dependencyNotation){
        configStatement1
        configStatement2
    }
}
Examples of advanced dependency declaration including:
  • Forcing certain dependency version in case of the conflict.
  • Excluding certain dependencies by name, group or both. More details about per-dependency exclusions can be found in docs for ModuleDependency.exclude(java.util.Map).
  • Avoiding transitive dependencies for certain dependency.
apply plugin: 'java' //so that I can declare 'implementation' dependencies

dependencies {
  implementation('org.hibernate:hibernate:3.1') {
    //in case of versions conflict '3.1' version of hibernate wins:
    force = true

    //excluding a particular transitive dependency:
    exclude module: 'cglib' //by artifact name
    exclude group: 'org.jmock' //by group
    exclude group: 'org.unwanted', module: 'iAmBuggy' //by both name and group

    //disabling all transitive dependencies of this dependency
    transitive = false
  }
}
More examples of advanced configuration, useful when dependency module has multiple artifacts: 
apply plugin: 'java' //so that I can declare 'implementation' dependencies

dependencies {
  //configuring dependency to specific configuration of the module
  implementation configuration: 'someConf', group: 'org.someOrg', name: 'someModule', version: '1.0'

  //configuring dependency on 'someLib' module
  implementation(group: 'org.myorg', name: 'someLib', version:'1.0') {
    //explicitly adding the dependency artifact:
    artifact {
      //useful when some artifact properties unconventional
      name = 'someArtifact' //artifact name different than module name
      extension = 'someExt'
      type = 'someType'
      classifier = 'someClassifier'
    }
  }
}

Dependency notations

There are several supported dependency notations. These are described below. For each dependency declared this way, a Dependency object is created. You can use this object to query or further configure the dependency.

You can also always add instances of Dependency directly:

configurationName <instance>

External dependencies

There are two notations supported for declaring a dependency on an external module. One is a string notation formatted this way:

configurationName "group:name:version:classifier@extension"

The other is a map notation:

configurationName group: group, name: name, version: version, classifier: classifier, ext: extension

In both notations, all properties, except name, are optional.

External dependencies are represented by a ExternalModuleDependency.

apply plugin: 'java'
//so that we can use 'implementation', 'testImplementation' for dependencies

dependencies {
  //for dependencies found in artifact repositories you can use
  //the string notation, e.g. group:name:version
  implementation 'commons-lang:commons-lang:2.6'
  testImplementation 'org.mockito:mockito:1.9.0-rc1'

  //map notation:
  implementation group: 'com.google.code.guice', name: 'guice', version: '1.0'
}

Project dependencies

To add a project dependency, you use the following notation:

configurationName project(':someProject')

The notation project(':projectA') is similar to the syntax you use when configuring a projectA in a multi-module gradle project.

By default, when you declare dependency to projectA, you actually declare dependency to the 'default' configuration of the projectA. If you need to depend on a specific configuration of projectA, use map notation for projects:

configurationName project(path: ':projectA', configuration: 'someOtherConfiguration')

Project dependencies are represented using a ProjectDependency.

File dependencies

You can also add a dependency using a FileCollection:

configurationName files('a file') 
apply plugin: 'java'
//so that we can use 'implementation', 'testImplementation' for dependencies

dependencies {
  //declaring arbitrary files as dependencies
  implementation files('hibernate.jar', 'libs/spring.jar')

  //putting all jars from 'libs' onto compile classpath
  implementation fileTree('libs')
}

File dependencies are represented using a SelfResolvingDependency.

Dependencies to other configurations

You can add a dependency using a Configuration.

When the configuration is from the same project as the target configuration, the target configuration is changed to extend from the provided configuration.

When the configuration is from a different project, a project dependency is added.

Gradle distribution specific dependencies

It is possible to depend on certain Gradle APIs or libraries that Gradle ships with. It is particularly useful for Gradle plugin development. Example:

//Our Gradle plugin is written in groovy
apply plugin: 'groovy'
//now we can use the 'implementation' configuration for declaring dependencies

dependencies {
  //we will use the Groovy version that ships with Gradle:
  implementation localGroovy()

  //our plugin requires Gradle API interfaces and classes to compile:
  implementation gradleApi()

  //we will use the Gradle test-kit to test build logic:
  testImplementation gradleTestKit()
}

Client module dependencies

To add a client module to a configuration you can use the notation:

configurationName module(moduleNotation) {
    module dependencies
}
The module notation is the same as the dependency notations described above, except that the classifier property is not available. Client modules are represented using a ClientModule.

  • Method Details

    • add

      @Nullable Dependency add(String configurationName, Object dependencyNotation)
      Adds a dependency to the given configuration.
      Parameters:
      configurationName - The name of the configuration.
      dependencyNotation - The dependency notation, in one of the notations described above.
      Returns:
      The dependency.

    • add

      Dependency add(String configurationName, Object dependencyNotation, Closure configureClosure)
      Adds a dependency to the given configuration, and configures the dependency using the given closure.
      Parameters:
      configurationName - The name of the configuration.
      dependencyNotation - The dependency notation, in one of the notations described above.
      configureClosure - The closure to use to configure the dependency.
      Returns:
      The dependency.

    • create

      Dependency create(Object dependencyNotation)
      Creates a dependency without adding it to a configuration.
      Parameters:
      dependencyNotation - The dependency notation, in one of the notations described above.
      Returns:
      The dependency.

    • create

      Dependency create(Object dependencyNotation, Closure configureClosure)
      Creates a dependency without adding it to a configuration, and configures the dependency using the given closure.
      Parameters:
      dependencyNotation - The dependency notation, in one of the notations described above.
      configureClosure - The closure to use to configure the dependency.
      Returns:
      The dependency.

    • module

      Dependency module(Object notation)
      Creates a dependency on a client module.
      Parameters:
      notation - The module notation, in one of the notations described above.
      Returns:
      The dependency.

    • module

      Dependency module(Object notation, Closure configureClosure)
      Creates a dependency on a client module. The dependency is configured using the given closure before it is returned.
      Parameters:
      notation - The module notation, in one of the notations described above.
      configureClosure - The closure to use to configure the dependency.
      Returns:
      The dependency.

    • project

      Dependency project(Map<String,?> notation)
      Creates a dependency on a project.
      Parameters:
      notation - The project notation, in one of the notations described above.
      Returns:
      The dependency.

    • gradleApi

      Dependency gradleApi()
      Creates a dependency on the API of the current version of Gradle.
      Returns:
      The dependency.

    • gradleTestKit

      Dependency gradleTestKit()
      Creates a dependency on the Gradle test-kit API.
      Returns:
      The dependency.
      Since:
      2.6

    • localGroovy

      Dependency localGroovy()
      Creates a dependency on the Groovy that is distributed with the current version of Gradle.
      Returns:
      The dependency.

    • getConstraints

      @Incubating DependencyConstraintHandler getConstraints()
      Returns the dependency constraint handler for this project.
      Returns:
      the dependency constraint handler for this project
      Since:
      4.5

    • constraints

      @Incubating void constraints(Action<? super DependencyConstraintHandler> configureAction)
      Configures dependency constraint for this project.

      This method executes the given action against the DependencyConstraintHandler for this project.

      Parameters:
      configureAction - the action to use to configure module metadata
      Since:
      4.5

    • getComponents

      ComponentMetadataHandler getComponents()
      Returns the component metadata handler for this project. The returned handler can be used for adding rules that modify the metadata of depended-on software components.
      Returns:
      the component metadata handler for this project
      Since:
      1.8

    • components

      void components(Action<? super ComponentMetadataHandler> configureAction)
      Configures component metadata for this project.

      This method executes the given action against the ComponentMetadataHandler for this project.

      Parameters:
      configureAction - the action to use to configure module metadata
      Since:
      1.8

    • getModules

      ComponentModuleMetadataHandler getModules()
      Returns the component module metadata handler for this project. The returned handler can be used for adding rules that modify the metadata of depended-on software components.
      Returns:
      the component module metadata handler for this project
      Since:
      2.2

    • modules

      void modules(Action<? super ComponentModuleMetadataHandler> configureAction)
      Configures module metadata for this project.

      This method executes the given action against the ComponentModuleMetadataHandler for this project.

      Parameters:
      configureAction - the action to use to configure module metadata
      Since:
      2.2

    • createArtifactResolutionQuery

      ArtifactResolutionQuery createArtifactResolutionQuery()
      Creates an artifact resolution query.
      Since:
      2.0

    • attributesSchema

      AttributesSchema attributesSchema(Action<? super AttributesSchema> configureAction)
      Configures the attributes schema. The action is passed a AttributesSchema instance.
      Parameters:
      configureAction - the configure action
      Returns:
      the configured schema
      Since:
      3.4

    • getAttributesSchema

      AttributesSchema getAttributesSchema()
      Returns the attributes schema for this handler.
      Returns:
      the attributes schema
      Since:
      3.4

    • getArtifactTypes

      @Incubating ArtifactTypeContainer getArtifactTypes()
      Returns the artifact type definitions for this handler.
      Since:
      4.0

    • artifactTypes

      @Incubating void artifactTypes(Action<? super ArtifactTypeContainer> configureAction)
      Configures the artifact type definitions for this handler.
      Since:
      4.0

    • registerTransform

      @Deprecated void registerTransform(Action<? super VariantTransform> registrationAction)
      Deprecated.
      use registerTransform(Class, Action) instead.
      Registers an artifact transform.
      Since:
      3.5
      See Also:

    • registerTransform

      @Incubating <T extends TransformParameters> void registerTransform(Class<? extends TransformAction<T>> actionType, Action<? super TransformSpec<T>> registrationAction)
      Registers an artifact transform.

      The registration action needs to specify the from and to attributes. It may also provide parameters for the transform action by using TransformSpec.parameters(Action).

      For example:

      // You have a transform action like this:
abstract class MyTransform implements TransformAction<Parameters> {
    interface Parameters extends TransformParameters {
        @Input
        Property<String> getStringParameter();
        @InputFiles
        ConfigurableFileCollection getInputFiles();
    }

    void transform(TransformOutputs outputs) {
        // ...
    }
}

// Then you can register the action like this:

def artifactType = Attribute.of('artifactType', String)

dependencies.registerTransform(MyTransform) {
    from.attribute(artifactType, "jar")
    to.attribute(artifactType, "java-classes-directory")

    parameters {
        stringParameter.set("Some string")
        inputFiles.from("my-input-file")
    }
}
      Since:
      5.3
      See Also:

    • platform

      @Incubating Dependency platform(Object notation)
      Declares a dependency on a platform. If the target coordinates represent multiple potential components, the platform component will be selected, instead of the library.
      Parameters:
      notation - the coordinates of the platform
      Since:
      5.0

    • platform

      @Incubating Dependency platform(Object notation, Action<? super Dependency> configureAction)
      Declares a dependency on a platform. If the target coordinates represent multiple potential components, the platform component will be selected, instead of the library.
      Parameters:
      notation - the coordinates of the platform
      configureAction - the dependency configuration block
      Since:
      5.0

    • enforcedPlatform

      @Incubating Dependency enforcedPlatform(Object notation)
      Declares a dependency on an enforced platform. If the target coordinates represent multiple potential components, the platform component will be selected, instead of the library. An enforced platform is a platform for which the direct dependencies are forced, meaning that they would override any other version found in the graph.
      Parameters:
      notation - the coordinates of the platform
      Since:
      5.0

    • enforcedPlatform

      @Incubating Dependency enforcedPlatform(Object notation, Action<? super Dependency> configureAction)
      Declares a dependency on an enforced platform. If the target coordinates represent multiple potential components, the platform component will be selected, instead of the library. An enforced platform is a platform for which the direct dependencies are forced, meaning that they would override any other version found in the graph.
      Parameters:
      notation - the coordinates of the platform
      configureAction - the dependency configuration block
      Since:
      5.0