* One notable exception is the computation of the early {@code session.rootDirectory}
 * property which happens very early.  The implementation used in this case
 * will be discovered using the JDK service mechanism.
 *
 * The default implementation will look for a {@code .mvn} child directory
 * or a {@code pom.xml} containing the {@code root="true"} attribute.
 */
public interface RootLocator {

    @Override
    public String getVersion() {
        if (version != null) {
            return version;
        } else {
            return artifact.getVersion();
        }
    }

    // Revise these three methods when MRESOLVER-233 is delivered
    @Override
    public Artifact setVersion(String version) {
        String current = getVersion();

import java.util.List;

import org.apache.maven.api.Service;
import org.apache.maven.api.annotations.Experimental;
import org.apache.maven.api.annotations.Nonnull;
import org.apache.maven.api.annotations.Nullable;

/**
 * Service used to interact with the end user.
 *
 * @since 4.0.0
 */
@Experimental
public interface Prompter extends Service {
    /**
     * Prompts the user for a string.
     *

 */
package org.apache.maven.api.services;

import java.util.Optional;

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

public interface ExtensibleEnumRegistry<T extends ExtensibleEnum> extends Service {
    @Nonnull
    Optional<T> lookup(@Nonnull String id);

    @Nonnull
    default T require(@Nonnull String id) {

package org.apache.maven.api.services;

import org.apache.maven.api.Service;
import org.apache.maven.api.annotations.Experimental;
import org.apache.maven.api.annotations.Nonnull;
import org.apache.maven.api.model.Model;

/**
 * Provides the super POM that all models implicitly inherit from.
 *
 * @since 4.0.0
 */
@Experimental
public interface SuperPomProvider extends Service {

    /**

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

import org.apache.maven.api.ArtifactCoordinate;
import org.apache.maven.api.Service;
import org.apache.maven.api.Session;
import org.apache.maven.api.annotations.Consumer;
import org.apache.maven.api.annotations.Experimental;
import org.apache.maven.api.annotations.Nonnull;

/**

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

/**
 *
 * @since 4.0.0
 */
@Experimental
public interface LocalRepositoryManager extends Service {

    /**
     * Gets the relative path for a locally installed artifact.

import java.util.function.Consumer;

import org.apache.maven.api.Service;
import org.apache.maven.api.Session;
import org.apache.maven.api.annotations.Nonnull;
import org.apache.maven.api.model.Dependency;
import org.apache.maven.api.model.Parent;

/**
 * Resolves a POM from its coordinates.
 */
public interface ModelResolver extends Service {

    /**

    @SuppressWarnings("unchecked")
    public <T extends Service> T getService(Class<T> clazz) throws NoSuchElementException {
        T t = (T) services.computeIfAbsent(clazz, this::lookup);
        if (t == null) {
            throw new NoSuchElementException(clazz.getName());
        }
        return t;
    }

    private Service lookup(Class<? extends Service> c) {
        try {
            return lookup.lookup(c);

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

import java.util.function.Consumer;

import org.apache.maven.plugin.descriptor.PluginDescriptor;

/**
 * Service responsible for checking if plugin's prerequisites are met.
 */
@FunctionalInterface
public interface MavenPluginPrerequisitesChecker extends Consumer<PluginDescriptor> {
    /**
     *
     * @param pluginDescriptor