return artifact.getGroupId() + ':' + artifact.getArtifactId() + ':' + artifact.getBaseVersion();
    }

    protected String getKey(String classifier, String extension) {
        return classifier + ':' + extension;
    }

    @Override
    public String getGroupId() {
        return metadata.getGroupId();
    }

    @Override
    public String getArtifactId() {

  define for each {{{../maven-model/maven.html#class_dependency}dependency type}} information on the artifact
  (classifier, extension, language) and how to manage it as dependency (add to classpath, include dependencies).

  They are replaced in Maven 4 with Maven 4 API Core's {{{../api/maven-api-core/apidocs/org/apache/maven/api/Type.html}Dependency Types}},

     * method "filters" out in WHICH artifact are we interested in, but it intentionally neglects extension as
     * ArtifactDescriptorReader modifies extension to "pom" during collect. So all we have to rely on is GAV only.
     */
    static boolean isInScope(Artifact artifact, Artifact nodeArtifact) {

 * This API does not try to cover all the requirements out there, just the basic ones, and is intentionally simple.
 * If plugin or extension needs anything more complex feature wise (i.e. HTTP range support or alike) it should
 * probably roll its own.
 * <p>

import org.codehaus.plexus.component.repository.exception.ComponentLookupException;
import org.codehaus.plexus.testing.PlexusTest;
import org.eclipse.sisu.Typed;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.mockito.Mock;
import org.mockito.junit.jupiter.MockitoExtension;

import static org.junit.jupiter.api.Assertions.assertNotNull;
import static org.junit.jupiter.api.Assertions.assertNotSame;

        String groupId = artifact.getGroupId();
        String artifactId = artifact.getArtifactId();
        String version = artifact.getBaseVersion();
        String classifier = artifact.getClassifier();
        String extension = artifact.getExtension();
        Path repo = getProjectLocalRepo();
        return repo.resolve(groupId)
                .resolve(artifactId)
                .resolve(version)
                .resolve(artifactId

                break;
            default:
                throw new IllegalArgumentException("Bad artifact coordinates " + coord
                        + ", expected format is <groupId>:<artifactId>[:<extension>[:<classifier>]]:<version>");
        }
        return s;
    }

META-INF/MANIFEST.MF Manifest-Version: 1.0 Archiver-Version: Plexus Archiver Created-By: Apache Maven Built-By: Brett Build-Jdk: 1.5.0_04 Extension-Name: maven-plugin-api Specification-Title: Maven is a project development management and com prehension tool. Based on the concept of a project object model: buil ds, dependency management, documentation creation, site publication, and distribution publication are all controlled from the declarative file. Maven can be extended by plugins to utilise...

 */
class TestArtifactHandler implements ArtifactHandler {

    private String type;

    private String extension;

    public TestArtifactHandler(String type) {
        this(type, type);
    }

    public TestArtifactHandler(String type, String extension) {
        this.type = type;
        this.extension = extension;
    }

    @Override
    public String getClassifier() {
        return null;
    }

            // MNG-5368: Log a message instead of returning 'null' silently.
            this.logger.error(
                    String.format(
                            "Invalid version specification '%s' creating extension artifact '%s:%s:%s'.",
                            version, groupId, artifactId, version),
                    e);

            return null;
        }