this.versionScheme = requireNonNull(versionScheme, "versionScheme");
    }

    @Override
    public Version parseVersion(String version) {
        requireNonNull(version, "version");
        return new DefaultVersion(versionScheme, version);
    }

    @Override
    public VersionRange parseVersionRange(String range) {
        requireNonNull(range, "range");

        requireNonNull(dependency, "dependency cannot be null");
        String prop = dependency.getArtifact().getProperty(MavenArtifactProperties.INCLUDES_DEPENDENCIES, "");
        return !Boolean.parseBoolean(prop);
    }

    @Override
    public DependencyTraverser deriveChildTraverser(DependencyCollectionContext context) {
        requireNonNull(context, "context cannot be null");
        return this;

@Named
@Singleton
public class DefaultToolchainsXmlFactory implements ToolchainsXmlFactory {
    @Override
    public PersistedToolchains read(@Nonnull XmlReaderRequest request) throws XmlReaderException {
        Objects.requireNonNull(request, "request");
        Reader reader = request.getReader();
        InputStream inputStream = request.getInputStream();
        if (reader == null && inputStream == null) {

@Named
@Singleton
public class DefaultToolchainsXmlFactory implements ToolchainsXmlFactory {
    @Override
    public PersistedToolchains read(@Nonnull XmlReaderRequest request) throws XmlReaderException {
        Objects.requireNonNull(request, "request");
        Reader reader = request.getReader();
        InputStream inputStream = request.getInputStream();
        if (reader == null && inputStream == null) {

 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.artifact.handler;

import static java.util.Objects.requireNonNull;

/**
 */
public class DefaultArtifactHandler implements ArtifactHandler {
    private final String type;

    private String extension;

    private String classifier;

        return new ArrayList<>(sorter.getSortedProjects());
    }

    public List<MavenProject> getDownstreamProjects(MavenProject project, boolean transitive) {
        Objects.requireNonNull(project, "project cannot be null");

        Set<String> projectIds = new HashSet<>();

        getDownstreamProjects(ProjectSorter.getId(project), projectIds, transitive);

            String extension,
            String classifier,
            boolean includesDependencies,
            PathType... pathTypes) {
        this.id = requireNonNull(id, "id");
        this.language = requireNonNull(language, "language");
        this.extension = requireNonNull(extension, "extension");
        this.classifier = classifier;
        this.includesDependencies = includesDependencies;

            super(id);
            this.projectScope = Objects.requireNonNull(projectScope);
            this.dependencyScopes =
                    Collections.unmodifiableSet(new HashSet<>(Arrays.asList(Objects.requireNonNull(dependencyScopes))));
        }

        @Override
        public ProjectScope projectScope() {
            return projectScope;
        }

import static java.util.Objects.requireNonNull;

/**
 * A class building reverse tree using {@link CollectStepData} trace data provided in {@link RepositoryEvent}
 * events fired during collection.
 *
 * @since 3.9.0
 */
class ReverseTreeRepositoryListener extends AbstractRepositoryListener {
    @Override
    public void artifactResolved(RepositoryEvent event) {
        requireNonNull(event, "event cannot be null");

import javax.inject.Named;
import javax.inject.Provider;

import org.eclipse.aether.RepositorySystem;
import org.eclipse.sisu.EagerSingleton;
import org.eclipse.sisu.PreDestroy;

import static java.util.Objects.requireNonNull;

/**
 * Maven internal component that bridges container "shut down" to {@link RepositorySystem#shutdown()}.
 *
 * @since 3.9.0
 */
@Named
@EagerSingleton
final class ResolverLifecycle {