* Object#equals}.
 *
 * <p>The collections returned by {@code keySet} and {@code asMap} iterate through the keys
 * according to the key comparator ordering or the natural ordering of the keys. Similarly, {@code
 * get}, {@code removeAll}, and {@code replaceValues} return collections that iterate through the
 * values according to the value comparator ordering or the natural ordering of the values. The

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;

                @Override
                public Iterator<Entry<String, String>> iterator() {
                  return new Iterator<Entry<String, String>>() {

                    final Iterator<Entry<String, String>> iterator = map.entrySet().iterator();

                    @Override
                    public void remove() {
                      iterator.remove();
                    }

        assertThat(lru.get("aaa"), is("111"));
        Iterator<String> i = lru.keySet().iterator();
        assertThat(i.next(), is("bbb"));
        assertThat(i.next(), is("ccc"));
        assertThat(i.next(), is("aaa"));
        lru.put("ddd", "444");
        assertThat(lru.size(), is(3));
        assertThat(lru.get("bbb"), is(nullValue()));
        i = lru.keySet().iterator();
        assertThat(i.next(), is("ccc"));

      }
      return false;
    }

    @Override
    public void clear() {
      AbstractTable.this.clear();
    }

    @Override
    public Iterator<Table.Cell<R, C, V>> iterator() {
      return cellIterator();
    }

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

  public void testRemoveAtIndexConcurrentWithIteration() {
    assertThrows(
        ConcurrentModificationException.class,
        () -> {
          Iterator<E> iterator = collection.iterator();
          getList().remove(getNumElements() / 2);
          iterator.next();
        });
  }

  @ListFeature.Require(SUPPORTS_REMOVE_WITH_INDEX)
  @CollectionSize.Require(absent = ZERO)
  public void testRemoveAtIndex_last() {

        @Override
        protected Set<Entry<K, V>> delegate() {
          return entries;
        }

        @Override
        public Iterator<Entry<K, V>> iterator() {
          return UnmodifiableEntry.transformEntries(super.iterator());
        }

        @Override
        public Object[] toArray() {
          /*

    assertFalse(underlying.containsKey("b"));

    Iterator<String> keyIterator = keys.iterator();
    keyIterator.next();
    keyIterator.remove();
    assertFalse(underlying.containsKey("c"));

    Collection<String> values = map.values();
    values.remove("4");
    assertFalse(underlying.containsKey("d"));

    Iterator<String> valueIterator = values.iterator();
    valueIterator.next();
    valueIterator.remove();

   */
  Comparator<? super T> comparator();

  /**
   * Returns an iterator over elements of type {@code T}. The elements are returned in nondecreasing
   * order according to the associated {@link #comparator}.
   */
  @Override
  Iterator<T> iterator();

   */
  Comparator<? super T> comparator();

  /**
   * Returns an iterator over elements of type {@code T}. The elements are returned in nondecreasing
   * order according to the associated {@link #comparator}.
   */
  @Override
  Iterator<T> iterator();