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

import org.apache.maven.artifact.Artifact;

/**
 * This exception is thrown if an application attempts to attach
 * two of the same artifacts to a single project.
 *
 * TODO Make this a checked exception, and modify the API of MavenProjectHelper.
 * Currently, this modification would create compatibility problems for existing plugins.

import org.apache.maven.api.Service;
import org.apache.maven.api.Session;
import org.apache.maven.api.annotations.Experimental;

/**
 * Resolves the artifact, i.e download the file when required and attach it to the artifact
 *
 * @since 4.0.0
 */
@Experimental
public interface ArtifactResolver extends Service {

    /**
     * @param request {@link ArtifactResolverRequest}

                new PropertiesAsMap(((DefaultProject) project).getProject().getProperties()));
    }

    @Override
    public Optional<Project> getExecutionProject(Project project) {
        // Session keep tracks of the Project per project id,
        // so we cannot use session.getProject(p) for forked projects
        // which are temporary clones
        return Optional.ofNullable(getMavenProject(project).getExecutionProject())

            </configuration>
          </execution>
          <execution>
            <id>install</id>
            <phase>generate-sources</phase>
            <goals>
              <goal>set</goal>
              <goal>attach-pom</goal>
              <goal>install</goal>
            </goals>
            <configuration>
              <mainFile>dependency-1.jar</mainFile>
            </configuration>
          </execution>

import org.apache.maven.artifact.metadata.ArtifactMetadata;
import org.apache.maven.artifact.repository.ArtifactRepository;
import org.apache.maven.artifact.repository.metadata.RepositoryMetadataStoreException;

/**
 * Attach a POM to an artifact.
 *
 */
@Deprecated
public class ProjectArtifactMetadata extends AbstractArtifactMetadata {
    private final File file;

    public ProjectArtifactMetadata(Artifact artifact) {

      </plugin>
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>build-helper-maven-plugin</artifactId>
        <executions>
          <execution>
            <goals>
              <goal>attach-artifact</goal>
            </goals>
            <configuration>
              <artifacts>
                <artifact>
                  <file>${basedir}/src/main/mdo/maven.mdo</file>
                  <type>mdo</type>