* under the License.
 */
package org.apache.maven.lifecycle.internal.stub;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.CompletionService;
import java.util.concurrent.Future;
import java.util.concurrent.FutureTask;
import java.util.concurrent.TimeUnit;

        Supplier<T> s = asSupplier(supplier);
        if (cache == null) {
            return s.get();
        } else {
            return cache.computeIfAbsent(groupId, artifactId, version, tag, s);
        }
    }

    private static <T> T cache(ModelCache cache, Source source, String tag, Callable<T> supplier) {

            }
            if (failure) {
                return results;
            }

            List<Callable<List<ProjectBuildingResult>>> callables = interimResults.stream()
                    .map(interimResult ->
                            (Callable<List<ProjectBuildingResult>>) () -> doBuild(projectIndex, interimResult))
                    .collect(Collectors.toList());

            try {

import javax.inject.Inject;
import javax.inject.Named;
import javax.inject.Singleton;

import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.Callable;
import java.util.concurrent.CompletionService;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorCompletionService;
import java.util.concurrent.ExecutorService;

import java.io.ByteArrayOutputStream;
import java.io.PrintStream;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.Callable;
import java.util.concurrent.CompletionService;
import java.util.concurrent.ExecutorCompletionService;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;

     */
    @Nonnull
    Optional<Source> getUserToolchainsSource();

    @Nonnull
    static ToolchainsBuilderRequest build(
            @Nonnull Session session, @Nullable Source globalToolchainsSource, @Nullable Source userToolchainsSource) {
        return builder()
                .session(nonNull(session, "session cannot be null"))
                .globalToolchainsSource(globalToolchainsSource)

         * found at the given file or in the given directory.
         *
         * @since 4.0.0
         */
        @Nullable
        Path locateExistingPom(@Nonnull Path project);
    }

    @Nullable
    ModelSource resolve(@Nonnull ModelLocator modelLocator, @Nonnull String relative);

    @Nonnull
    static ModelSource fromPath(@Nonnull Path path) {

     */
    <T> boolean replace(@Nonnull Key<T> key, @Nullable T oldValue, @Nullable T newValue);

    /**
     * Gets the session data associated with the specified key.
     *
     * @param key the key for which to retrieve the session data, must not be {@code null}
     * @return the session data associated with the key or {@code null} if none
     */
    @Nullable
    <T> T get(@Nonnull Key<T> key);

    /**

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

/**
 * An XML writer request.
 *
 * @since 4.0.0
 * @param <T> the object type to read
 */
@Experimental
public interface XmlWriterRequest<T> {

    @Nullable
    Path getPath();

    @Nullable
    OutputStream getOutputStream();

    @Nullable
    Writer getWriter();

    @Nonnull
    T getContent();

                return new Exclusion() {
                    @Nullable
                    @Override
                    public String getGroupId() {
                        return exclusion.getGroupId();
                    }

                    @Nullable
                    @Override
                    public String getArtifactId() {