IncidentEdgeSet<N> incident =
        new IncidentEdgeSet<N>(this, node, IncidentEdgeSet.EdgeType.BOTH) {
          @Override
          public UnmodifiableIterator<EndpointPair<N>> iterator() {
            if (graph.isDirected()) {
              return Iterators.unmodifiableIterator(
                  Iterators.concat(
                      Iterators.transform(
                          graph.predecessors(node).iterator(),

  public static <T extends @Nullable Object> UnmodifiableIterator<T> unmodifiableIterator(
      Iterator<? extends T> iterator) {
    checkNotNull(iterator);
    if (iterator instanceof UnmodifiableIterator) {
      @SuppressWarnings("unchecked") // Since it's unmodifiable, the covariant cast is safe
      UnmodifiableIterator<T> result = (UnmodifiableIterator<T>) iterator;
      return result;
    }

  final transient Collection<E> delegate;

  ForwardingImmutableCollection(Collection<E> delegate) {
    this.delegate = delegate;
  }

  @Override
  public UnmodifiableIterator<E> iterator() {
    return Iterators.unmodifiableIterator(delegate.iterator());
  }

  @Override
  public boolean contains(@Nullable Object object) {
    return object != null && delegate.contains(object);
  }

  @Override

    return new AbstractSet<E>() {
      @Override
      public UnmodifiableIterator<E> iterator() {
        Iterable<E> incidentEdges =
            (selfLoopCount == 0)
                ? Iterables.concat(inEdgeMap.keySet(), outEdgeMap.keySet())
                : Sets.union(inEdgeMap.keySet(), outEdgeMap.keySet());
        return Iterators.unmodifiableIterator(incidentEdges.iterator());
      }

      @Override

    return new AbstractSet<E>() {
      @Override
      public UnmodifiableIterator<E> iterator() {
        Iterable<E> incidentEdges =
            (selfLoopCount == 0)
                ? Iterables.concat(inEdgeMap.keySet(), outEdgeMap.keySet())
                : Sets.union(inEdgeMap.keySet(), outEdgeMap.keySet());
        return Iterators.unmodifiableIterator(incidentEdges.iterator());
      }

      @Override

  }

  final Set<K> unmodifiableKeySet() {
    return new AbstractSet<K>() {
      @Override
      public UnmodifiableIterator<K> iterator() {
        Iterator<Entry<K, V>> entryIterator = backingMap.entrySet().iterator();

        return new UnmodifiableIterator<K>() {
          @Override
          public boolean hasNext() {
            return entryIterator.hasNext();
          }

 */

package com.google.common.graph;

import static com.google.common.base.Preconditions.checkNotNull;

import com.google.common.collect.AbstractIterator;
import com.google.common.collect.UnmodifiableIterator;
import java.util.AbstractSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import org.jspecify.annotations.Nullable;

/**

    return delegateList().equals(obj);
  }

  @Override
  public int hashCode() {
    return delegateList().hashCode();
  }

  @Override
  public UnmodifiableIterator<E> iterator() {
    return Iterators.unmodifiableIterator(delegateList().iterator());
  }

  @Override
  public boolean contains(@Nullable Object object) {
    return object != null && delegateList().contains(object);
  }

import static com.google.common.base.Preconditions.checkNotNull;

import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterators;
import com.google.common.collect.UnmodifiableIterator;
import java.util.AbstractSet;
import java.util.Map;
import org.jspecify.annotations.Nullable;

/**
 * A class to represent the set of edges connecting an (implicit) origin node to a target node.
 *

    this.map = map;
  }

  @Override
  public int size() {
    return map.size();
  }

  @Override
  public UnmodifiableIterator<V> iterator() {
    return new UnmodifiableIterator<V>() {
      final UnmodifiableIterator<Entry<K, V>> entryItr = map.entrySet().iterator();

      @Override
      public boolean hasNext() {
        return entryItr.hasNext();
      }

      @Override