ReferenceEntry<K, V> next = head.getNextInWriteQueue();
      return (next == head) ? null : next;
    }

    @Override
    public @Nullable ReferenceEntry<K, V> poll() {
      ReferenceEntry<K, V> next = head.getNextInWriteQueue();
      if (next == head) {
        return null;
      }

      remove(next);
      return next;
    }

    @Override

      private final StrongKeyStrongValueEntry<K, V> next;

      LinkedStrongKeyStrongValueEntry(K key, int hash, StrongKeyStrongValueEntry<K, V> next) {
        super(key, hash);
        this.next = next;
      }

      @Override
      public StrongKeyStrongValueEntry<K, V> getNext() {
        return next;
      }
    }

      ReferenceEntry<K, V> next = head.getNextInWriteQueue();
      return (next == head) ? null : next;
    }

    @Override
    public @Nullable ReferenceEntry<K, V> poll() {
      ReferenceEntry<K, V> next = head.getNextInWriteQueue();
      if (next == head) {
        return null;
      }

      remove(next);
      return next;
    }

    @Override

      private final StrongKeyStrongValueEntry<K, V> next;

      LinkedStrongKeyStrongValueEntry(K key, int hash, StrongKeyStrongValueEntry<K, V> next) {
        super(key, hash);
        this.next = next;
      }

      @Override
      public StrongKeyStrongValueEntry<K, V> getNext() {
        return next;
      }
    }

 *
 * Each derivation can capture the next value or any intermediate objects for later closing.
 *
 * <p>A step can be the input to at most one derived step. Once you transform its value, catch its
 * exception, or combine it with others, you cannot do anything else with it, including declare it
 * to be the last step of the pipeline.
 *
 * <h4>Transforming</h4>
 *

   *     iterator().next()} or {@link Iterables#getFirst} instead.
   */
  @SuppressWarnings("nullness") // Unsafe, but we can't do much about it now.
  public final Optional<@NonNull E> first() {
    Iterator<E> iterator = getDelegate().iterator();
    return iterator.hasNext() ? Optional.of(iterator.next()) : Optional.absent();
  }

  /**

   *     iterator().next()} or {@link Iterables#getFirst} instead.
   */
  @SuppressWarnings("nullness") // Unsafe, but we can't do much about it now.
  public final Optional<@NonNull E> first() {
    Iterator<E> iterator = getDelegate().iterator();
    return iterator.hasNext() ? Optional.of(iterator.next()) : Optional.absent();
  }

  /**

    }
    Entry<K, ? extends V> entry1 = entryItr.next();
    K key1 = entry1.getKey();
    V value1 = entry1.getValue();
    checkEntryNotNull(key1, value1);
    // Do something that works for j2cl, where we can't call getDeclaredClass():
    EnumMap<K, V> enumMap = new EnumMap<>(singletonMap(key1, value1));
    while (entryItr.hasNext()) {
      Entry<K, ? extends V> entry = entryItr.next();
      K key = entry.getKey();

    }
    Entry<K, ? extends V> entry1 = entryItr.next();
    K key1 = entry1.getKey();
    V value1 = entry1.getValue();
    checkEntryNotNull(key1, value1);
    // Do something that works for j2cl, where we can't call getDeclaredClass():
    EnumMap<K, V> enumMap = new EnumMap<>(singletonMap(key1, value1));
    while (entryItr.hasNext()) {
      Entry<K, ? extends V> entry = entryItr.next();
      K key = entry.getKey();

## 0.128.3 (2026-02-06)

### Refactors

* ♻️ Re-implement `on_event` in FastAPI for compatibility with the next Starlette, while keeping backwards compatibility. PR [#14851](https://github.com/fastapi/fastapi/pull/14851) by [@tiangolo](https://github.com/tiangolo).

### Upgrades