import javax.inject.Singleton;

import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.factory.ArtifactFactory;
import org.apache.maven.artifact.repository.ArtifactRepository;
import org.apache.maven.artifact.versioning.ArtifactVersion;
import org.apache.maven.repository.legacy.metadata.ArtifactMetadataRetrievalException;

        List<ProducedArtifact> artifacts = getArtifacts();
        return artifacts.size() == 2 ? Optional.of(artifacts.get(1)) : Optional.empty();
    }

    /**
     * {@return the project artifacts as immutable list}. Elements are the project POM artifact and the artifact
     * produced by this project build, if applicable. Hence, the returned list may have one or two elements

    public void addArtifact(Artifact artifact) {
        if (artifacts == null) {
            artifacts = new LinkedHashSet<>();
        }

        artifacts.add(artifact);
    }

    public Set<Artifact> getArtifacts() {
        if (artifacts == null) {
            artifacts = new LinkedHashSet<>();
        }

        return artifacts;
    }

    public void setArtifacts(Set<Artifact> artifacts) {

        setForceUpdate(request.isForceUpdate());
    }

    public Artifact getArtifact() {
        return artifact;
    }

    public ArtifactResolutionRequest setArtifact(Artifact artifact) {
        this.artifact = artifact;

        return this;
    }

    public ArtifactResolutionRequest setArtifactDependencies(Set<Artifact> artifactDependencies) {
        this.artifactDependencies = artifactDependencies;

import java.util.List;

import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.repository.ArtifactRepository;
import org.apache.maven.artifact.repository.DefaultRepositoryRequest;
import org.apache.maven.artifact.repository.RepositoryRequest;
import org.apache.maven.artifact.resolver.ArtifactResolutionRequest;

/**
 * Forms a request to retrieve artifact metadata.
 *
 */
@Deprecated

 */
package org.apache.maven.artifact.resolver;

import org.apache.maven.artifact.Artifact;

/**
 * Indicates a cycle in the dependency graph.
 *
 */
public class CyclicDependencyException extends ArtifactResolutionException {
    private Artifact artifact;

    public CyclicDependencyException(String message, Artifact artifact) {
        super(message, artifact);
        this.artifact = artifact;
    }

    /**
     * Gets the group id of the constituent's artifact.
     *
     * @return The group id, never {@code null}.
     */
    String getGroupId();

    /**
     * Gets the artifact id of the constituent's artifact.
     *
     * @return The artifact id, never {@code null}.
     */
    String getArtifactId();

    /**
     * Gets the type of the constituent's artifact.
     *
     * @return The type, never {@code null}.

import java.util.Arrays;
import java.util.List;
import java.util.Properties;

import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.InvalidRepositoryException;
import org.apache.maven.artifact.repository.ArtifactRepository;
import org.apache.maven.artifact.resolver.ArtifactNotFoundException;
import org.apache.maven.artifact.resolver.ArtifactResolutionException;
import org.apache.maven.execution.MavenExecutionRequest;

     * {@return the identifier of the artifact}.
     */
    @Nonnull
    String getArtifactId();

    /**
     * Returns the classifier of the artifact.
     *
     * @return the classifier or an empty string if none, never {@code null}
     */
    @Nonnull
    String getClassifier();

    /**
     * {@return the specific version, range of versions, or meta-version of the artifact}.

 * under the License.
 */
package org.apache.maven.artifact;

/**
 * Exception that occurs when an artifact file is used, but has not been resolved.
 *
 * TODO it may be better for artifact.getFile() to throw it - perhaps it is a runtime exception?
 */
public class DependencyResolutionRequiredException extends Exception {
    public DependencyResolutionRequiredException(Artifact artifact) {