// the same instance can be provided multiple times under different Key's
        // deduplicate instances to avoid redundant beforeXXX/afterXXX callbacks
        IdentityHashMap<WeakMojoExecutionListener, Object> listeners = new IdentityHashMap<>();
        for (Object provided : getScopeState().provided()) {
            if (provided instanceof WeakMojoExecutionListener) {

        }
    }

    private TransferListenerAdapter(ArtifactTransferListener listener) {
        this.listener = listener;
        this.artifacts = new IdentityHashMap<>();
        this.transfers = new IdentityHashMap<>();
    }

    public void debug(String message) {}

    public void transferCompleted(TransferEvent transferEvent) {
        ArtifactTransferEvent event = wrap(transferEvent);

import javax.inject.Singleton;

import java.io.IOException;
import java.net.ConnectException;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.IdentityHashMap;
import java.util.List;
import java.util.Set;

import org.apache.maven.api.plugin.MojoException;
import org.apache.maven.lifecycle.LifecycleExecutionException;
import org.apache.maven.model.building.ModelProblem;

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

import java.util.ArrayList;
import java.util.Collection;
import java.util.IdentityHashMap;
import java.util.List;
import java.util.Map;
import java.util.Objects;

import org.apache.maven.execution.ProjectDependencyGraph;
import org.apache.maven.project.MavenProject;

/**

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

import java.util.Collections;
import java.util.IdentityHashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.CopyOnWriteArrayList;

import org.apache.maven.project.DependencyResolutionResult;
import org.apache.maven.project.MavenProject;

import com.google.common.collect.ImmutableMapEntry.NonTerminalImmutableMapEntry;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.io.Serializable;
import java.util.IdentityHashMap;
import java.util.function.BiConsumer;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**

    @GuardedBy("monitor")
    final Multiset<State> states = servicesByState.keys();

    @GuardedBy("monitor")
    final IdentityHashMap<Service, Stopwatch> startupTimers = new IdentityHashMap<>();

    /**
     * These two booleans are used to mark the state as ready to start.
     *
     * <p>{@link #ready}: is set by {@link #markReady} to indicate that all listeners have been

    @GuardedBy("monitor")
    final Multiset<State> states = servicesByState.keys();

    @GuardedBy("monitor")
    final IdentityHashMap<Service, Stopwatch> startupTimers = new IdentityHashMap<>();

    /**
     * These two booleans are used to mark the state as ready to start.
     *
     * <p>{@link #ready}: is set by {@link #markReady} to indicate that all listeners have been

   * an element in the set. For example, {@code contains} returns {@code false} when passed an
   * object that equals a set member, but isn't the same instance. This behavior is similar to the
   * way {@code IdentityHashMap} handles key lookups.
   *
   * @since 8.0
   */
  public static <E extends @Nullable Object> Set<E> newIdentityHashSet() {
    return Collections.newSetFromMap(Maps.<E, Boolean>newIdentityHashMap());
  }

            CollectionFeature.SERIALIZABLE,
            CollectionSize.ANY)
        .suppressing(suppressForConcurrentSkipListMap())
        .createTestSuite();
  }

  // TODO: IdentityHashMap, AbstractMap

  private static Map<String, String> toHashMap(Entry<String, String>[] entries) {
    return populate(new HashMap<String, String>(), entries);
  }