// GWT's ConcurrentHashMap is a wrapper around HashMap, but it rejects null keys, which matches
    // the behaviour of the non-GWT implementation of newConcurrentHashSet().
    // On the other hand HashSet might be better for code size if apps aren't
    // already using Collections.newSetFromMap and ConcurrentHashMap.
    return Collections.newSetFromMap(new ConcurrentHashMap<E, Boolean>());
  }

 *       contains all the right method <i>signatures</i> to implement {@link Iterable}, it does not
 *       actually do so, to avoid implying repeat-iterability.) {@code FluentIterable}, on the other
 *       hand, is multiple-use, and does implement {@link Iterable}.
 *   <li>Streams offer many features not found here, including {@code min/max}, {@code distinct},

   * Object#toString}.
   *
   * <p>If the target method call finishes before the limit is reached, the return value or
   * exception is propagated to the caller exactly as-is. If, on the other hand, the time limit is
   * reached, the proxy will attempt to abort the call to the target, and will throw an {@link
   * UncheckedTimeoutException} to the caller.
   *

bats eat cats?' for, you see, as she couldn't answer either
question, it didn't much matter which way she put it.  She felt
that she was dozing off, and had just begun to dream that she
was walking hand in hand with Dinah, and saying to her very
earnestly, `Now, Dinah, tell me the truth:  did you ever eat a
bat?' when suddenly, thump! thump! down she came upon a heap of
sticks and dry leaves, and the fall was over.

 * verbosity, and more, from the {@code get} and {@code set} methods. {@code Monitor} implements the
 * same efficient signaling as we had to hand-code in the {@code ReentrantLock} version above.
 * Finally, the programmer no longer has to hand-code the wait loop, and therefore doesn't have to
 * remember to use {@code while} instead of {@code if}.
 *
 * <pre>{@code
 * public class SafeBox<V> {

   * type variable's bound has been partially resolved. As long as the type variable "identity"
   * matches.
   *
   * <p>On the other hand, if for example we are resolving {@code List<A extends B>} to {@code
   * List<A extends String>}, we need to compare that {@code <A extends B>} is unequal to {@code <A

     *            k * k <= x          <  (k + 1) * (k + 1)
     * (double) (k * k) <= (double) x <= (double) ((k + 1) * (k + 1))
     *          since casting to double is nondecreasing.
     *          Note that the right-hand inequality is no longer strict.
     * Math.sqrt(k * k) <= Math.sqrt(x) <= Math.sqrt((k + 1) * (k + 1))
     *          since Math.sqrt is monotonic.

   * data written to it to the underlying {@link OutputStream}.
   *
   * <p>The {@link OutputStream} should not be written to before or after the hand-off.
   */
  // TODO(user): Evaluate whether it makes sense to always piggyback the computation of a
  // HashCode on an existing OutputStream, compared to creating a separate OutputStream that could

   * read from it to the underlying {@link InputStream}.
   *
   * <p>The {@link InputStream} should not be read from before or after the hand-off.
   */
  public HashingInputStream(HashFunction hashFunction, InputStream in) {
    super(checkNotNull(in));
    this.hasher = checkNotNull(hashFunction.newHasher());
  }

  /**

  private void readMoreChars() throws IOException {
    // Possibilities:
    // 1) array has space available on right-hand side (between limit and capacity)
    // 2) array has space available on left-hand side (before position)
    // 3) array has no space available
    //
    // In case 2 we shift the existing chars to the left, and in case 3 we create a bigger