assertArgumentNotNull("iterator", iterator);

        return () -> new IndexedIterator<>(iterator);
    }

    /**
     * Constructs an instance.
     *
     * @param iterator the iterator (must not be {@literal null})
     */
    public IndexedIterator(final Iterator<T> iterator) {
        assertArgumentNotNull("iterator", iterator);

        this.iterator = iterator;

    multimap.put("foo", 2);
    multimap.put("bar", 3);
    Collection<Entry<String, Integer>> entries = multimap.entries();
    Iterator<Entry<String, Integer>> iterator = entries.iterator();
    Entry<String, Integer> entrya = iterator.next();
    Entry<String, Integer> entryb = iterator.next();

    assertEquals(2, (int) multimap.get("foo").set(0, 4));
    assertFalse(multimap.containsEntry("foo", 2));

    assertEquals("b", iterator.previous());
    assertThrows(UnsupportedOperationException.class, () -> iterator.add("c"));
  }

  @SuppressWarnings("DoNotCall")
  public void testSet() {
    ListIterator<String> iterator = create();

    assertTrue(iterator.hasNext());
    assertEquals("a", iterator.next());
    assertEquals("b", iterator.next());
    assertEquals("b", iterator.previous());

    return (MinimalIterable) of(elements.toArray());
  }

  private @Nullable Iterator<E> iterator;

  private MinimalIterable(Iterator<E> iterator) {
    this.iterator = iterator;
  }

  @Override
  public Iterator<E> iterator() {
    if (iterator == null) {
      // TODO: throw something else? Do we worry that people's code and tests

  public void testPutAbsentConcurrentWithEntrySetIteration() {
    assertThrows(
        ConcurrentModificationException.class,
        () -> {
          Iterator<Entry<K, V>> iterator = getMap().entrySet().iterator();
          put(e3());
          iterator.next();
        });
  }

  @MapFeature.Require({FAILS_FAST_ON_CONCURRENT_MODIFICATION, SUPPORTS_PUT})
  @CollectionSize.Require(absent = ZERO)

              throw new NoSuchElementException();
            }
            return array[i++];
          }
        };

    assertTrue(iterator.hasNext());
    assertEquals("a", iterator.next());
    assertThrows(UnsupportedOperationException.class, () -> iterator.remove());
  }

package com.google.common.collect;

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

import com.google.common.annotations.GwtCompatible;
import java.util.Iterator;
import org.jspecify.annotations.Nullable;

/**
 * An iterator that transforms a backing iterator; for internal use. This avoids the object overhead
 * of constructing a {@link com.google.common.base.Function Function} for internal methods.
 *
 * @author Louis Wasserman

  public void testEntrySet_iteratorRemovePropagates() {
    Iterator<Multiset.Entry<E>> iterator = getMultiset().entrySet().iterator();
    assertTrue(
        "non-empty multiset.entrySet() iterator.hasNext() returned false", iterator.hasNext());
    assertEquals(
        "multiset.entrySet() iterator.next() returned incorrect entry",
        Multisets.immutableEntry(e0(), 1),
        iterator.next());
    assertFalse(

import jcifs.context.SingletonContext;

/**
 * Tests for NetServerFileEntryAdapterIterator.
 *
 * Intent: Validate iteration behavior, filtering, invalid inputs handling,
 * and delegation to the underlying iterator.
 */
@ExtendWith(MockitoExtension.class)
class NetServerFileEntryAdapterIteratorTest {

    @Mock
    NetServerEnumIterator delegate;

    @Mock
    ResourceFilter filter;

    @Mock

    } catch (IllegalArgumentException e) {
      return emptySet(comparator());
    }
  }

  @Nullable E higher(E e) {
    checkNotNull(e);
    Iterator<E> iterator = tailSet(e).iterator();
    while (iterator.hasNext()) {
      E higher = iterator.next();
      if (comparator().compare(e, higher) < 0) {
        return higher;
      }
    }
    return null;
  }

  public @Nullable E ceiling(E e) {