return policy == Policies.DISABLED
          ? new ReentrantLock(fair)
          // requireNonNull is safe because createNodes inserts an entry for every E.
          // (If the caller passes `null` for the `rank` parameter, this will throw, but that's OK.)
          : new CycleDetectingReentrantLock(requireNonNull(lockGraphNodes.get(rank)), fair);
    }

import javax.inject.Named;
import javax.inject.Provider;

import org.eclipse.aether.RepositorySystem;
import org.eclipse.sisu.EagerSingleton;
import org.eclipse.sisu.PreDestroy;

import static java.util.Objects.requireNonNull;

/**
 * Maven internal component that bridges container "shut down" to {@link RepositorySystem#shutdown()}.
 *
 * @since 3.9.0
 */
@Named
@EagerSingleton
final class ResolverLifecycle {

import static java.nio.file.attribute.AclEntryFlag.FILE_INHERIT;
import static java.nio.file.attribute.AclEntryType.ALLOW;
import static java.nio.file.attribute.PosixFilePermissions.asFileAttribute;
import static java.util.Objects.requireNonNull;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.collect.ImmutableList;

 * limitations under the License.
 */

package com.google.common.testing;

import static com.google.common.base.Preconditions.checkNotNull;
import static java.util.Objects.requireNonNull;

import com.google.common.annotations.GwtCompatible;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;

 * limitations under the License.
 */

package com.google.common.testing;

import static com.google.common.base.Preconditions.checkNotNull;
import static java.util.Objects.requireNonNull;

import com.google.common.annotations.GwtCompatible;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;

    }

    @Override
    public ValueSetLink<K, V> getPredecessorInValueSet() {
      return requireNonNull(predecessorInValueSet); // see the comment on the class fields
    }

    @Override
    public ValueSetLink<K, V> getSuccessorInValueSet() {
      return requireNonNull(successorInValueSet); // see the comment on the class fields
    }

    @Override

import static java.util.Objects.requireNonNull;

@Named
@Singleton
public class DefaultTransportProvider implements TransportProvider {
    private final org.eclipse.aether.spi.connector.transport.TransporterProvider transporterProvider;

    @Inject
    public DefaultTransportProvider(TransporterProvider transporterProvider) {
        this.transporterProvider = requireNonNull(transporterProvider);
    }

    @Override

import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluator;
import org.codehaus.plexus.configuration.PlexusConfiguration;

import static java.util.Objects.requireNonNull;

/**
 * Common implementations for plugin parameters configuration validation.
 *
 */
abstract class AbstractMavenPluginParametersValidator implements MavenPluginConfigurationValidator {

                Objects.requireNonNull(remoteRepositoryManager, "remoteRepositoryManager cannot be null");
        this.versionResolver = Objects.requireNonNull(versionResolver, "versionResolver cannot be null");
        this.versionRangeResolver = Objects.requireNonNull(versionRangeResolver, "versionRangeResolver cannot be null");
        this.artifactResolver = Objects.requireNonNull(artifactResolver, "artifactResolver cannot be null");

  private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException {
    stream.defaultReadObject();
    keyTypeOrObjectUnderJ2cl = (Class<K>) requireNonNull(stream.readObject());
    valueTypeOrObjectUnderJ2cl = (Class<V>) requireNonNull(stream.readObject());
    setDelegates(
        new EnumMap<K, V>(keyTypeOrObjectUnderJ2cl), new EnumMap<V, K>(valueTypeOrObjectUnderJ2cl));