hasher.putString("The quick brown fox jumps over the lazy dog", UTF_8).hash().toString());
    assertThrows(IllegalStateException.class, () -> hasher.putInt(42));
  }

  public void testHashTwice() {
    Hasher hasher = Hashing.hmacMd5(MD5_KEY).newHasher();

    assertEquals(
        "9753980fe94daa8ecaa82216519393a9",
        hasher.putString("The quick brown fox jumps over the lazy dog", UTF_8).hash().toString());

    }
  }

  /** A {@code ListIterator} over values for a specified key. */
  private class ValueForKeyIterator implements ListIterator<V> {
    @ParametricNullness final K key;
    int nextIndex;
    @CheckForNull Node<K, V> next;
    @CheckForNull Node<K, V> current;
    @CheckForNull Node<K, V> previous;

    /** Constructs a new iterator over all values for the specified key. */

    } catch (UnsupportedOperationException expected) {
    }
  }

  /**
   * Verifies that an Iterator is unmodifiable.
   *
   * <p>This test only works with iterators that iterate over a finite set.
   */
  public static void assertIteratorIsUnmodifiable(Iterator<?> iterator) {
    while (iterator.hasNext()) {
      iterator.next();
      try {
        iterator.remove();

   * reached, but not the other, the shorter iterable is considered to be less than the longer one.
   * For example, a lexicographical natural ordering over integers considers {@code [] < [1] < [1,
   * 1] < [1, 2] < [2]}.
   *
   * <p>Note that {@code Collections.reverseOrder(lexicographical(comparator))} is not equivalent to

      return ((Set<?>) iterable).contains(element) ? 1 : 0;
    }
    return Iterators.frequency(iterable.iterator(), element);
  }

  /**
   * Returns an iterable whose iterators cycle indefinitely over the elements of {@code iterable}.
   *
   * <p>That iterator supports {@code remove()} if {@code iterable.iterator()} does. After {@code

    throwable.printStackTrace(new PrintWriter(stringWriter));
    return stringWriter.toString();
  }

  /**
   * Returns the stack trace of {@code throwable}, possibly providing slower iteration over the full
   * trace but faster iteration over parts of the trace. Here, "slower" and "faster" are defined in
   * comparison to the normal way to access the stack trace, {@link Throwable#getStackTrace()

    throwable.printStackTrace(new PrintWriter(stringWriter));
    return stringWriter.toString();
  }

  /**
   * Returns the stack trace of {@code throwable}, possibly providing slower iteration over the full
   * trace but faster iteration over parts of the trace. Here, "slower" and "faster" are defined in
   * comparison to the normal way to access the stack trace, {@link Throwable#getStackTrace()

   * <p><b>Warning:</b> a new random seed for these functions is chosen each time the {@code
   * Hashing} class is loaded. <b>Do not use this method</b> if hash codes may escape the current
   * process in any way, for example being sent over RPC, or saved to disk. For a general-purpose,
   * non-cryptographic hash function that will never change behavior, we suggest {@link
   * #murmur3_128}.
   *

   * satisfied at the time of signal, and has since been modified by some other thread to be
   * non-satisfied before reacquiring the lock, and that other thread takes over the responsibility
   * of signaling the next waiter.
   *
   * Unlike the underlying Condition, if we are not careful, an interrupt *can* cause a signal to be

   * specified is included. To create a copy of a {@code SortedSet} that preserves the comparator,
   * call {@link #copyOfSorted} instead. This method iterates over {@code elements} at most once.
   *
   * <p>Note that if {@code s} is a {@code Set<String>}, then {@code ImmutableSortedSet.copyOf(s)}
   * returns an {@code ImmutableSortedSet<String>} containing each of the strings in {@code s},