import java.util.ArrayList;
import java.util.Comparator;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.function.Supplier;
import java.util.stream.Collectors;

import com.google.inject.AbstractModule;
import com.google.inject.binder.AnnotatedBindingBuilder;
import com.google.inject.name.Names;

        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) {
        Supplier<T> s = asSupplier(supplier);

        public int hashCode() {
            return hash;
        }
    }

    static class CachingSupplier<T> implements Supplier<T> {
        final Supplier<T> supplier;
        volatile Object value;

        CachingSupplier(Supplier<T> supplier) {
            this.supplier = supplier;
        }

        @Override
        @SuppressWarnings({"unchecked", "checkstyle:InnerAssignment"})
        public T get() {

                }
            }
            return model;
        }

        public Model computeIfAbsent(Supplier<Model> supplier) {
            if (!set) {
                synchronized (this) {
                    if (!set) {
                        this.set = true;
                        this.model = supplier.get();
                        this.notifyAll();
                    }
                }
            }

import java.nio.file.Path;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Objects;
import java.util.concurrent.atomic.AtomicReference;
import java.util.function.Supplier;

import org.apache.maven.artifact.DefaultArtifact;
import org.apache.maven.internal.transformation.TransformationFailedException;
import org.apache.maven.model.building.ModelBuildingException;

        throw (T) t; // rely on vacuous cast
    }

    static class LazyMap<K, V> extends AbstractMap<K, V> {
        private final Supplier<Map<K, V>> supplier;
        private volatile Map<K, V> delegate;

        LazyMap(Supplier<Map<K, V>> supplier) {
            this.supplier = supplier;
        }

        @Override
        public Set<Entry<K, V>> entrySet() {
            if (delegate == null) {

    /* MNG-786*/
    @Test
    void testProfileModules() throws Exception {
        PomTestWrapper pom = buildPom("profile-module", "a");
        assertEquals("test-prop", pom.getValue("properties[1]/b")); // verifies profile applied
        assertEquals(4, ((List<?>) pom.getValue("modules")).size());
        assertEquals("module-2", pom.getValue("modules[1]"));
        assertEquals("module-1", pom.getValue("modules[2]"));

 * model builder.
 *
 */
public interface ModelCache {

    <T> T computeIfAbsent(String groupId, String artifactId, String version, String tag, Supplier<T> data);

    <T> T computeIfAbsent(Source path, String tag, Supplier<T> data);

import java.util.Properties;

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

/**
 * Centralized class for Maven Core feature information.
 * Features configured are supposed to be final in a given maven session.
 *
 * @since 4.0.0
 */
public final class Features {

    /**
     * Name of the Maven user property to enable or disable the build/consumer POM feature.
     */

    }

    public PluginDescriptor get(Key cacheKey) {
        return clone(descriptors.get(cacheKey));
    }

    @Override
    public PluginDescriptor get(Key key, PluginDescriptorSupplier supplier)
            throws PluginDescriptorParsingException, PluginResolutionException, InvalidPluginDescriptorException {

        try {
            PluginDescriptor desc = descriptors.get(key);
            if (desc == null) {