<T> T computeIfAbsent(@Nonnull Key<T> key, @Nonnull Supplier<T> supplier);

    /**
     * Create a key using the given class as an identifier and as the type of the object.
     */
    static <T> Key<T> key(Class<T> clazz) {
        return new Key<>(clazz, clazz);
    }

    /**
     * Create a key using the given class and id.
     */
    static <T> Key<T> key(Class<T> clazz, Object id) {

     */
    public static class ObjectBasedValueSource extends AbstractValueSource {

        private final Object root;

        /**
         * Construct a new value source, using the supplied object as the root from
         * which to start, and using expressions split at the dot ('.') to navigate
         * the object graph beneath this root.
         * @param root the root of the graph.
         */

/**
 * Maven relocation source.
 * Note: implementations of this component should avoid the "default" name (has special meaning in Eclipse Sisu) and
 * explicitly order implementations using Sisu priorities.
 *
 * @since 4.0.0
 */
public interface MavenArtifactRelocationSource {
    /**
     * Returns {@link Artifact} instance where to relocate to, or {@code null}.
     *

        if (Files.isDirectory(path)) {
            /*
             * Package hierarchy: only one module with descriptor at the root.
             * This is the layout of output directories in projects using the
             * classical (Java 8 and before) way to organize source files.
             */
            Path file = path.resolve(MODULE_INFO);
            if (Files.isRegularFile(file)) {

     */
    public Set<String> getExportedPackages() {
        return packages;
    }

    /**
     * The key that can must used to identify the configuration using the
     * {@link javax.inject.Named} annotation.
     */
    public String getKey() {
        return key;
    }

    /**
     * Returns the configuration for this extension.
     */

import org.eclipse.aether.resolution.ArtifactRequest;
import org.eclipse.aether.util.artifact.ArtifactIdUtils;

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

         * remotely resolved snapshot artifact gets passed into pathOf(). So producing a proper local artifact path
         * using DefaultRepositoryLayout requires us to enforce usage of the artifact's base version. This
         * transformation however contradicts the other use case of precisely obeying the repository's layout. The below

    /**
     * Creates a derived session using the given local repository.
     *
     * @param localRepository the new local repository
     * @return the derived session
     * @throws NullPointerException if {@code localRepository} is null
     */
    @Nonnull
    Session withLocalRepository(@Nonnull LocalRepository localRepository);

    /**
     * Creates a derived session using the given remote repositories.
     *

        if (!outputDirectory.toFile().exists()) {
            return true;
        }

        try (Stream<Path> outputFiles = Files.walk(outputDirectory)) {
            // Not using File#lastModified() to avoid a Linux JDK8 milliseconds precision bug: JDK-8177809.
            long artifactLastModified =
                    Files.getLastModifiedTime(packagedArtifactFile.toPath()).toMillis();

     */
    String BOM = "bom";

    /**
     * Artifact type name for a JAR file that can be placed either on the class-path or on the module-path.
     * The path (classes or modules) is chosen by the plugin, possibly using heuristic rules.
     * This is the behavior of Maven 3.
     */
    String JAR = "jar";

    /**
     * Artifact type name for a fat-JAR file that can be only on the class-path.