* the order of a depth-first pre-order traversal. "Pre-order" implies that nodes appear in the
   * {@code Iterable} in the order in which they are first visited.
   *
   * <p><b>Example:</b> The following graph with {@code startNode} {@code a} would return nodes in
   * the order {@code abecfd} (assuming successors are returned in alphabetical order).
   *
   * <pre>{@code
   * b ---- a ---- d
   * |      |

    InputStream in = new ByteArrayInputStream(PRE_FILLED_100);
    byte[] b = ByteStreams.toByteArray(in, 100);
    assertThat(b).isEqualTo(PRE_FILLED_100);
  }

  public void testToByteArray_withSize_givenSmallerSize() throws IOException {
    InputStream in = new ByteArrayInputStream(PRE_FILLED_100);
    byte[] b = ByteStreams.toByteArray(in, 80);
    assertThat(b).isEqualTo(PRE_FILLED_100);
  }

 *
 * <pre>{@code
 * ListenableFuture<Boolean> adminIsLoggedIn =
 *     FluentFuture.from(usersDatabase.getAdminUser())
 *         .transform(User::getId, directExecutor())
 *         .transform(ActivityService::isLoggedIn, threadPool)
 *         .catching(RpcException.class, e -> false, directExecutor());
 * }</pre>
 *
 * <h3>Alternatives</h3>
 *
 * <h4>Frameworks</h4>
 *

   *
   * <pre>
   * for (Foo foo : foos) {
   *   try {
   *     foo.bar();
   *   } catch (BarException | RuntimeException | Error t) {
   *     failure = t;
   *   }
   * }
   * if (failure != null) {
   *   throwIfInstanceOf(failure, BarException.class);
   *   throwIfUnchecked(failure);
   *   throw new AssertionError(failure);
   * }
   * </pre>
   *
   * @since 20.0
   */

   *
   * <pre>
   * for (Foo foo : foos) {
   *   try {
   *     foo.bar();
   *   } catch (BarException | RuntimeException | Error t) {
   *     failure = t;
   *   }
   * }
   * if (failure != null) {
   *   throwIfInstanceOf(failure, BarException.class);
   *   throwIfUnchecked(failure);
   *   throw new AssertionError(failure);
   * }
   * </pre>
   *
   * @since 20.0
   */

 * then Lock B, while another thread acquires Lock B, and then Lock A:
 *
 * <pre>
 * Thread1: acquire(LockA) --X acquire(LockB)
 * Thread2: acquire(LockB) --X acquire(LockA)
 * </pre>
 *
 * <p>Neither thread will progress because each is waiting for the other. In more complex
 * applications, cycles can arise from interactions among more than 2 locks:
 *
 * <pre>
 * Thread1: acquire(LockA) --X acquire(LockB)

 *
 * <p>Example usage of {@code ComparisonChain}:
 *
 * <pre>{@code
 * public int compareTo(Foo that) {
 *   return ComparisonChain.start()
 *       .compare(this.aString, that.aString)
 *       .compare(this.anInt, that.anInt)
 *       .compare(this.anEnum, that.anEnum, Ordering.natural().nullsLast())
 *       .result();
 * }
 * }</pre>
 *

 *
 * <pre>{@code
 * ContiguousSet.create(Range.closed(5, 42), DiscreteDomain.integers())
 * }</pre>
 *
 * <p>Note that because bounded ranges over {@code int} and {@code long} values are so common, this
 * particular example can be written as just:
 *
 * <pre>{@code
 * ContiguousSet.closed(5, 42)
 * }</pre>
 *

   * static final} multimaps ("constant multimaps"). Example:
   *
   * <pre>{@code
   * static final Multimap<String, Integer> STRING_TO_INTEGER_MULTIMAP =
   *     new ImmutableListMultimap.Builder<String, Integer>()
   *         .put("one", 1)
   *         .putAll("several", 1, 2, 3)
   *         .putAll("many", 1, 2, 3, 4, 5)
   *         .build();
   * }</pre>
   *

 * final WeakHashMap<Object, Object> map = new WeakHashMap<>();
 * map.put(new Object(), Boolean.TRUE);
 * GcFinalization.awaitDone(new FinalizationPredicate() {
 *   public boolean isDone() {
 *     return map.isEmpty();
 *   }
 * });
 * }</pre>
 *
 * <p>Even if your non-test code does not use finalization, you can use this class to test for
 * leaks, by ensuring that objects are no longer strongly referenced:
 *
 * <pre>{@code