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[[how_to_resolve_specific_artifacts]]
= How to Resolve Specific Artifacts from a Module Dependency with Gradle

Gradle resolves module dependencies by looking for metadata files (`.module`, `.pom`, or `ivy.xml`) and a default artifact (usually a JAR).
If none of these files are found, the build fails.
In some cases, you may need to customize how Gradle resolves artifacts.

== Why Use Custom Artifact Resolution?

You might need to tweak artifact resolution in the following scenarios:

* The dependency provides a **non-standard artifact** (e.g., a ZIP file) without metadata.
* The module metadata declares **multiple artifacts** (e.g., an Ivy dependency descriptor).
* You want to **download only a specific artifact** without transitive dependencies.

== Step 1: Resolving an Artifact Without Metadata

Let’s say you want to build a web application that uses JavaScript libraries, such as **jQuery**, and download them from a repository instead of checking them into version control.

Google Hosted Libraries provides open-source JavaScript libraries.
Using **artifact-only notation**, you can fetch a JavaScript file like `jquery.js`.

The `@` character separates the dependency’s coordinates from the artifact’s file extension:

====
include::sample[dir="snippets/how-to/dependency-management/dependency-management/dependency-management/declaringDependencies-artifactOnly/kotlin",files="build.gradle.kts[tags=artifact-only-dependency-declaration]"]
include::sample[dir="snippets/how-to/dependency-management/dependency-management/dependency-management/declaringDependencies-artifactOnly/groovy",files="build.gradle[tags=artifact-only-dependency-declaration]"]
====

WARNING: Declaring dependencies with a custom extension (e.g. `@zip`, `@jar`, or `@custom`) disables metadata resolution. Gradle treats this as a request for a specific artifact, skipping variant-aware resolution and component metadata. You may need to provide metadata with a custom <<component_metadata_rules.adoc#component-metadata-rules,component metadata rule>>.

== Step 2: Resolving an Artifact with a Classifier

Some libraries provide multiple variations or **flavors** of an artifact.
In Java, a library may publish:

* A compiled artifact with class files.
* A separate artifact containing **source code**.
* Another one with **Javadocs**.

Similarly, in JavaScript, libraries often have:

* An **uncompressed** version.
* A **minified** version (optimized for production).

To specify a particular variation, you can use a **classifier**.
In Gradle, classifiers allow you to fetch a **specific** artifact within a module.

Instead of downloading the uncompressed `jquery.js` file, you can fetch the **minified** version (`jquery.min.js`) by specifying the classifier `min`:

====
include::sample[dir="snippets/how-to/dependency-management/dependency-management/dependency-management/declaringDependencies-artifactOnlyWithClassifier/kotlin",files="build.gradle.kts[tags=artifact-only-dependency-declaration]"]
include::sample[dir="snippets/how-to/dependency-management/dependency-management/dependency-management/declaringDependencies-artifactOnlyWithClassifier/groovy",files="build.gradle[tags=artifact-only-dependency-declaration]"]
====

== Summary

Gradle can fetch **non-Java** artifacts like JavaScript libraries from external repositories:

* Use **artifact-only notation (`@`)** when resolving dependencies that lack metadata.
* Use **classifiers** to specify different versions or variations of an artifact.
