Gradle Release Notes

Version 2.3-rc-1

Gradle 2.3 brings some nice new capabilities to dependency management and IDE support, as well as improvements to some core plugins.

A long requested feature has been the ability to access metadata artifacts like ivy.xml and pom.xml, that Gradle uses to perform dependency resolution. Using the Artifact Query API, you now have direct access to these raw metadata artifacts. This could be useful for generating an offline repository, inspecting the files for custom metadata, and much more.

IDE support in Gradle continues to improve, and Gradle 2.3 brings enhancements to the Gradle tooling API together with numerous bug fixes in our IDE plugins. Of note, this release brings much better integration with the Eclipse Web Tools Platform via the eclipse-wtp plugin.

As always, this Gradle release benefits from a large number of community contributions. These include substantial enhancements to the antlr, compare-gradle-builds and application plugins, as well as many bug fixes and improvements.

Table Of Contents

New and noteworthy

Here are the new features introduced in this Gradle release.

Access Ivy and Maven metadata artifacts via the Artifact Query API incubating feature

Gradle 2.0 introduced an incubating query API for resolving component artifacts.

Gradle 2.3 extends this API to allow for retrieving the metadata artifacts for Ivy and Maven modules. This means that a build can access the raw ivy.xml or module.pom file that Gradle used when resolving a dependency.

Given that the dependency is resolved from an Ivy repository, the Ivy descriptor artifact can be retrieved as follows:

task resolveIvyDescriptorFiles {
    doLast {
        def componentIds = configurations.compile.incoming.resolutionResult.allDependencies.collect { it.selected.id }

        def result = dependencies.createArtifactResolutionQuery()
            .forComponents(componentIds)
            .withArtifacts(IvyModule, IvyDescriptorArtifact)
            .execute()

        for (component in result.resolvedComponents) {
            component.getArtifacts(IvyDescriptorArtifact).each { assert it.file.name == 'ivy.xml' }
        }
    }
}

For a dependency that is resolved from a Maven repository, the Maven POM artifact can be retrieved as follows:

task resolveMavenPomFiles {
    doLast {
        def componentIds = configurations.compile.incoming.resolutionResult.allDependencies.collect { it.selected.id }

        def result = dependencies.createArtifactResolutionQuery()
            .forComponents(componentIds)
            .withArtifacts(MavenModule, MavenPomArtifact)
            .execute()

        for(component in result.resolvedComponents) {
            component.getArtifacts(MavenPomArtifact).each { assert it.file.name == 'some-artifact-1.0.pom' }
        }
    }
}

See the ArtifactResolutionQuery API reference for more details.

Component metadata rule enhancements incubating feature

Gradle 2.0 introduced 'component metadata rules', allowing certain aspects of dependency metadata to be modified based on custom build logic. For example, these rules can be used to specify that all components produced by a particular organisation have a custom 'status scheme', or that all components for a particular Ivy module with a custom 'status' attribute should be considered 'changing'.

In this release, the interface for defining component metadata rules has been enhanced. It is now possible to define rules that only apply to a particular module, as well as rules that apply to all components.

Note that components.eachComponent has been replaced with components.all, with the former being deprecated for removal in Gradle 2.4.

dependencies {
    components {
        // This rule applies to all modules
        all { ComponentMetadataDetails details ->
            if (details.group == "my.org" && details.status == "integration") {
                details.changing = true
            }
        }

        // This rule applies to only the "my.org:api" module
        withModule("my.org:api") { ComponentMetadetails details ->
            details.statusScheme = [ "testing", "candidate", "release" ]
        }
    }
}

Furthermore, rules can now also be specified as rule source objects, allowing them to be defined more easily in Java code:

dependencies {
    components {
        // This rule uses a rule source object that applies only to the "my.org:api" module
        withModule("my.org:api", new CustomStatusRule()) // See class definition below
    }
}

class CustomStatusRule {
    @Mutate
    void setComponentStatus(ComponentMetadataDetails details) {
        if (details.status == "integration") {
            details.status = "testing"
        }
    }
}

See the userguide section on component metadata rules for further information.

Improvements to the ANTLR plugin

Gradle has built-in support for parser generation using ANTLR using the ANTLR Plugin. Gradle 2.3 contains improvements to this support.

Adding to the existing support for ANTLR version 2.x, Gradle now supports ANTLR versions 3.x and 4.x of . To use ANTLR version 3 or 4 in a build, simply add the correct dependency to the antlr configuration:

apply plugin: "java"
apply plugin: "antlr"

repositories() {
    jcenter()
}

dependencies {
    antlr 'org.antlr:antlr4:4.3'
}

Additionally, the AntlrTask now executes ANTLR in a separate process. This allows more fine grained control over memory settings for the ANTLR process.

See the user guide chapter on the Antlr Plugin for further details.

These improvements were contributed by Rob Upcraft.

Build Comparison plugin now compares nested archives incubating feature

The Gradle Build Comparison plugin provides support for comparing the outcomes (e.g. the produced binary archives) of two builds. This support is greatly improved in Gradle 2.3, with the ability to compare entries of nested archives. A common type of nested archive that benefits from this change is a WAR file containing JAR files.

Previously, when comparing an archive for changes, the entries of that archive were treated as binary blobs. So Gradle would detect if a particular entry had changed, but would not inspect more deeply to see how it had changed. As of Gradle 2.3, entries of archive entries are inspected recursively where possible. This means that archive entries that are themselves archives are compared entry by entry.

This feature was contributed by Björn Kautler.

Better integration with Eclipse Web Tools Platform

In this release, support for the Eclipse Web Tools Platform via the eclipse-wtp plugin has been vastly improved.

Previous versions of this plugin were highly dependent on having the ear or war plugin applied. By removing this dependency, Gradle 2.3 enables users to leverage the Eclipse WTP support in more circumstances. Examples where this may be useful include projects producing a plain EJB module, or projects that prefer to configure facets directly on the Eclipse project.

A further improvement in this release is that generated Eclipse .classpath files now include correct dependency attributes (GRADLE-1422), fixing the case where certain Gradle builds could not be easily exported to Eclipse.

Thanks to Andreas Schmid, who contributed many of these improvements.

Tooling API improvements

The Gradle tooling API provides a stable API that tools such as IDEs can use to embed Gradle.

In Gradle 2.3, the tooling API now supports generating colored build output, identical to that generated by Gradle on the command-line. This feature was contributed by Lari Hotari.

When using the GradleConnector to create a tooling API connection, the method GradleConnector.useBuildDistribution() can now be used to explicitly declare that the distribution defined by the target Gradle build should be used.

New PluginManager interface for applying and managing plugins by id incubating feature

In the past, the PluginContainer API has been used for applying and querying plugins. This interface has a number of problems, including only supporting instances of Plugin, providing mutation methods that are not properly supported, and requiring that plugin instances be instantiated immediately on applying.

Gradle 2.3 introduces a new PluginManager API which addresses these issues, fully supporting RuleSource plugins and dealing better with plugin identification. While PluginContainer is not deprecated, build authors should prefer to use PluginManager methods where possible.

Useful methods include:

These methods should be used when reacting to the presence of another plugin or for ad-hoc reporting.

Application plugin is integrated with the Distribution plugin

The Application Plugin now leverages the Distribution Plugin for doing packaging. By configuring the 'main' distribution, a packaged application is treated as any other distribution.

For example, you can use gradle installDist to create an image of your application, gradle distZip to create a ZIP distribution of your application, and gradle assemble to build all application distributions.

This feature was contributed by Sébastien Cogneau.

Groovy version upgraded to 2.3.9

Gradle 2.3 includes Groovy 2.3.9 (upgraded from Groovy 2.3.6 in Gradle 2.2.1).

This is a non breaking change. All build scripts and plugins that work with Gradle 2.2.1 should continue to work without change or recompilation.

Fixed issues

Deprecations

Features that have become superseded or irrelevant due to the natural evolution of Gradle become deprecated, and scheduled to be removed in the next major Gradle version (Gradle 3.0). See the User guide section on the “Feature Lifecycle” for more information.

The following are the newly deprecated items in this Gradle release. If you have concerns about a deprecation, please raise it via the Gradle Forums.

Renamed method on ComponentMetadataHandler

The eachComponent method on the incubating ComponentMetadataHandler interface has been deprecated and replaced with all.

As this is an incubating feature, the deprecated method will be removed in Gradle 2.4.

--no-color command-line option

The --no-color option has been replaced by the more general --console option. You can use gradle --console plain ... instead of gradle --no-color ....

The --no-color option will be removed in Gradle 3.0.

Deprecated 'installApp' task in Application Plugin

The installApp task of the application plugin is deprecated and will be removed in Gradle 3.0. You can use the installDist task instead.

Potential breaking changes

Major changes to incubating 'native-component' and 'jvm-component' plugins

As we develop a new configuration and component model for Gradle, we are also developing an underlying infrastructure to allow the easy implementation of plugins supporting new platforms (native/jvm/javascript) and languages (C/C++/Java/Scala/CoffeeScript).

This version of Gradle takes a big step in that direction, by migrating the existing component-based plugins to sit on top of this new infrastructure. This includes the incubating 'jvm-component' and 'java-lang' plugins, as well as all of the plugins providing support for building native applications.

Due to this, the DSL for defining native executables and libraries has fundamentally changed. The executables and libraries containers have been removed, and components are now added by type to the components container owned by the model registry. Another major change is that source sets for a component are now declared directly within the component definition, instead of being configured on the sources block.

For comparison, the following native components defined in Gradle 2.2:

libraries {
    hello {}
}

executables {
    main {}
}

sources {
    main {
        cpp {
            lib library: "hello"
            source {
                srcDir "src/source"
                include "**/*.cpp"
            }
            exportedHeaders {
                srcDir "src/include"
            }
        }
    }
}

are defined as follows in Gradle 2.3:

model {
    components {
        hello(NativeLibrarySpec)

        main(NativeExecutableSpec) {
            sources {
               cpp {
                    lib library: "hello"
                    source {
                        srcDir "src/source"
                        include "**/*.cpp"
                    }
                    exportedHeaders {
                        srcDir "src/include"
                    }
               }
            }
        }
    }
}

The new syntax is more flexible to be used across different component domains, and will continue to be enhanced in the future. Please take a look at the sample applications found in samples/native-binaries and samples/jvmComponents to get a better idea of how you may migrate your Gradle build to the new syntax.

Note that this functionality is a work-in-progress, and in some cases it may be preferable to remain on an earlier version of Gradle until it has stabilised.

AntlrTask has incremental task action

The AntlrTask now processes input files incrementally. To do so, the execute has been changed to accept an IncrementalTaskInputs parameter.

This will break any code that calls the execute method of this task directly.

Mapping of Maven version range selectors

The maven version declaration LATEST is mapped to latest.integration and RELEASE is mapped to latest.release when resolving a dependency from a maven repository. The reverse mapping is applied when generating a pom file in Gradle (e.g. for publishing via maven-publish or maven plugin).

Ivy dependency exclude rules

Previous versions of Gradle improperly handled the name attribute for dependency exclude rules. Instead of excluding the matching artifact(s), the whole module was excluded. This behavior has been fixed with this version of Gradle. Keep in mind that this change may cause a slightly different dependency resolution behavior if you heavily rely on Ivy excludes.

In this context, we also fixed the incorrect handling of the artifact attribute for module exclude rules. For more information see GRADLE-3147.

Manually declared facets in eclipse-wtp plugin

In previous Gradle versions, declaring a custom facet for eclipse.wtp caused the default facets to be removed.

eclipse {
    wtp {
        facet {
            facet name: 'someNeededFacet', version: '1.3'
        }
    }
}

This behaviour has been fixed in this version of Gradle: declaring a facet in this way will add to the set of default facets.

This fix was contributed by Andreas Schmid.

Tooling API GradleProject model includes implicit tasks

The GradleProject model now includes the implicit tasks of a project, such as help, tasks, dependencies, and wrapper.

This change could impact code that relied on the fact that these tasks formerly were absent from GradleProject.getTasks().

External contributions

We would like to thank the following community members for making contributions to this release of Gradle.

We love getting contributions from the Gradle community. For information on contributing, please see gradle.org/contribute.

Known issues

Known issues are problems that were discovered post release that are directly related to changes made in this release.