return delegate.higher(checkValid(e));
  }

  @Override
  public boolean isEmpty() {
    return delegate.isEmpty();
  }

  @Override
  public Iterator<E> iterator() {
    return delegate.iterator();
  }

  @Override
  public E last() {
    return delegate.last();
  }

  @Override
  public @Nullable E lower(E e) {
    return delegate.lower(checkValid(e));
  }

    }

    @Override
    Iterator<Entry<K, V>> entryIterator() {
      return Iterators.filter(unfiltered.entrySet().iterator(), entryPredicate);
    }

    @Override
    Iterator<Entry<K, V>> descendingEntryIterator() {
      return Iterators.filter(unfiltered.descendingMap().entrySet().iterator(), entryPredicate);
    }

    @Override
    public int size() {

    }

    @Override
    Iterator<Entry<K, V>> entryIterator() {
      return Iterators.filter(unfiltered.entrySet().iterator(), entryPredicate);
    }

    @Override
    Iterator<Entry<K, V>> descendingEntryIterator() {
      return Iterators.filter(unfiltered.descendingMap().entrySet().iterator(), entryPredicate);
    }

    @Override
    public int size() {

import java.io.Reader;
import java.util.Iterator;
import org.jspecify.annotations.Nullable;

/**
 * A {@link Reader} that concatenates multiple readers.
 *
 * @author Bin Zhu
 * @since 1.0
 */
@J2ktIncompatible
@GwtIncompatible
final class MultiReader extends Reader {
  private final Iterator<? extends CharSource> it;
  private @Nullable Reader current;

      }
    }
  }

  /**
   * Returns an iterator over the elements contained in this collection, <i>in no particular
   * order</i>.
   *
   * <p>The iterator is <i>fail-fast</i>: If the MinMaxPriorityQueue is modified at any time after
   * the iterator is created, in any way except through the iterator's own remove method, the
   * iterator will generally throw a {@link ConcurrentModificationException}. Thus, in the face of

        StringBuilder projectNames = new StringBuilder();
        Iterator<MavenProject> iterator = projects.iterator();
        while (iterator.hasNext()) {
            MavenProject project = iterator.next();
            projectNames.append(project.getGroupId()).append(":").append(project.getArtifactId());
            if (iterator.hasNext()) {
                projectNames.append(", ");
            }
        }

  }

  @Override
  UnmodifiableIterator<Entry<K, V>> entryIterator() {
    return new UnmodifiableIterator<Entry<K, V>>() {
      final Iterator<? extends Entry<K, ? extends ImmutableCollection<V>>> asMapItr =
          map.entrySet().iterator();
      @Nullable K currentKey = null;
      Iterator<V> valueItr = emptyIterator();

      @Override
      public boolean hasNext() {
        return valueItr.hasNext() || asMapItr.hasNext();

      }
    }
  }

  /**
   * Returns an iterator over the elements contained in this collection, <i>in no particular
   * order</i>.
   *
   * <p>The iterator is <i>fail-fast</i>: If the MinMaxPriorityQueue is modified at any time after
   * the iterator is created, in any way except through the iterator's own remove method, the
   * iterator will generally throw a {@link ConcurrentModificationException}. Thus, in the face of

    }

    @Override
    public boolean include(Artifact artifact) {
        String id = artifact.getGroupId() + ":" + artifact.getArtifactId();

        boolean matched = false;
        for (Iterator<String> i = patterns.iterator(); i.hasNext() & !matched; ) {
            // TODO what about wildcards? Just specifying groups? versions?
            if (id.equals(i.next())) {
                matched = true;
            }
        }

        AssertionFailedError.class,
        () ->
            assertEmpty(
                new Iterable<String>() {
                  @Override
                  public Iterator<String> iterator() {
                    return singleton("a").iterator();
                  }
                }));
  }

  public void testIsEmpty_map() {
    Map<Object, Object> map = new HashMap<>();
    assertEmpty(map);