*
 * // later
 * try { // get() will throw if the operation failed or was cancelled.
 *   UserName userName = userNameValueAndCloser.get();
 *   // do something with userName
 * } finally {
 *   userNameValueAndCloser.closeAsync();
 * }
 * }</pre>
 *
 * In this example, when {@code userNameValueAndCloser.closeAsync()} is called, the transaction and

      return ImmutableMap.of();
    }
    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();

      return ImmutableMap.of();
    }
    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();