*
 * @since 4.0.0
 * @see org.apache.maven.api.model.Dependency#getScope()
 * @see org.apache.maven.api.services.DependencyResolver
 */
@Experimental
@Immutable
public enum DependencyScope {

    /**
     * None. Allows you to declare dependencies (for example to alter reactor build order) but in reality dependencies
     * in this scope are not part of any path scope.
     */

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

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

/**
 * Storage location for metadata
 *
 * @since 4.0.0
 */
@Experimental
public enum MetadataStorage {
    GROUP,
    ARTIFACT,
    VERSION

     * @return the type
     */
    @Nonnull
    @Override
    default Type require(@Nonnull String id) {
        return lookup(id).orElseThrow(() -> new IllegalArgumentException("Unknown extensible enum value '" + id + "'"));
    }

import org.apache.maven.project.MavenProject;

/**
 * Holds data relevant for an execution event.
 *
 */
public interface ExecutionEvent {

    /**
     * The possible types of execution events.
     */
    enum Type {
        ProjectDiscoveryStarted,
        SessionStarted,
        SessionEnded,
        ProjectSkipped,
        ProjectStarted,
        ProjectSucceeded,
        ProjectFailed,
        MojoSkipped,

                throw new CycleDetectedException(
                        "Edge between '" + from + "' and '" + to + "' introduces to cycle in the graph", cycle);
            }
        }
    }

    private enum DfsState {
        VISITING,
        VISITED
    }

    private static List<String> visitCycle(
            Map<String, Set<String>> graph,
            Collection<String> children,

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

import java.util.*;

class Graph {
    private enum DfsState {
        VISITING,
        VISITED
    }

    final Map<String, Vertex> vertices = new LinkedHashMap<>();

    public Vertex getVertex(String id) {
        return vertices.get(id);
    }

/**
 * Request used to build a {@link org.apache.maven.api.Project} using
 * the {@link ProjectBuilder} service.
 *
 * TODO: replace ModelRepositoryHolder with just the enum for the strategy
 * TODO: replace validation level with an enum (though, we usually need just a boolean)
 *
 * @since 4.0.0
 */
@Experimental
@Immutable
public interface ModelBuilderRequest {

    /**

     */
    @Nonnull
    Severity getSeverity();

    /**
     * The different severity levels for a problem, in decreasing order.
     *
     * @since 4.0.0
     */
    @Experimental
    enum Severity {
        FATAL, //
        ERROR, //
        WARNING //
    }

import org.apache.maven.api.annotations.Nonnull;

/**
 * An SPI interface to extend Maven with a new enum value.
 *
 * @param <T> The type of extensible enum to extend
 */
@Experimental
@Consumer
public interface ExtensibleEnumProvider<T extends ExtensibleEnum> extends SpiService {

    /**
     * Registers new values for the T extensible enum.
     *
     * @return a collection of T instances to register
     */
    @Nonnull

 * A path scope is used to determine the kind of build or class path that will be built when resolving
 * dependencies using the {@link org.apache.maven.api.services.DependencyResolver} service.
 * <p>
 * This extensible enum has four defined values, {@link #MAIN_COMPILE}, {@link #MAIN_RUNTIME},
 * {@link #TEST_COMPILE} and {@link #TEST_RUNTIME}, but can be extended by registering a
 * {@code org.apache.maven.api.spi.PathScopeProvider}.
 * <p>