* is set to {@code null}.
   *
   * <p>Like the {@link #toArray()} method, this method acts as bridge between array-based and
   * collection-based APIs. Further, this method allows precise control over the runtime type of the
   * output array, and may, under certain circumstances, be used to save allocation costs.
   *

      open = isOpen
    }
    if (cancel) {
      // RST this stream to prevent additional data from being sent. This is safe because the input
      // stream is closed (we won't use any further bytes) and the output stream is either finished
      // or closed (so RSTing both streams doesn't cause harm).
      ******@****.***(ErrorCode.CANCEL, null)
    } else if (!open) {
      connection.removeStream(id)

   * two). These considerations lead us to have a field of type DuplicateKey in the Builder, which
   * will remember the first duplicate key we encountered. All later calls to buildOrThrow() can
   * mention that key with its values. Further duplicates might be added in the meantime but since
   * builders only ever accumulate entries it will always be valid to throw from buildOrThrow() with
   * the first duplicate.
   */

    /**
     * Create or update incoming headers, creating the corresponding streams if necessary. Frames
     * that trigger this are HEADERS and PUSH_PROMISE.
     *
     * @param inFinished true if the sender will not send further frames.
     * @param streamId the stream owning these headers.
     * @param associatedStreamId the stream that triggered the sender to create this stream.
     */
    fun headers(
      inFinished: Boolean,

   *
   * @throws NullPointerException if {@code elements} contains a null element
   */
  public static <E> ImmutableList<E> copyOf(Iterator<? extends E> elements) {
    // We special-case for 0 or 1 elements, but going further is madness.
    if (!elements.hasNext()) {
      return of();
    }
    E first = elements.next();
    if (!elements.hasNext()) {
      return of(first);
    } else {

 *       source as they are read from it. A source that provides such readers will not be reusable,
 *       and operations that read from the stream (including {@link #length()}, in some
 *       implementations) will prevent further operations from completing as expected.
 * </ul>
 *
 * @since 14.0
 * @author Colin Decker
 */
@J2ktIncompatible
@GwtIncompatible
public abstract class CharSource {

 *       source as they are read from it. A source that provides such readers will not be reusable,
 *       and operations that read from the stream (including {@link #length()}, in some
 *       implementations) will prevent further operations from completing as expected.
 * </ul>
 *
 * @since 14.0
 * @author Colin Decker
 */
@J2ktIncompatible
@GwtIncompatible
public abstract class CharSource {

   * lookup would fail with an IllegalAccessException. That may then trigger use of Unsafe (possibly
   * with a warning under recent JVMs), or it may fall back even further to
   * AtomicReferenceFieldUpdaterAtomicHelper, which would fail with a similar problem to
   * VarHandleAtomicHelperMaker, forcing us all the way to SynchronizedHelper.
   *

   * lookup would fail with an IllegalAccessException. That may then trigger use of Unsafe (possibly
   * with a warning under recent JVMs), or it may fall back even further to
   * AtomicReferenceFieldUpdaterAtomicHelper, which would fail with a similar problem to
   * VarHandleAtomicHelperMaker, forcing us all the way to SynchronizedHelper.
   *

    assertEquals(s.substring(0, 1), matcher.trimFrom(s));
    assertEquals(1, matcher.countIn(s));
  }

  /**
   * Checks that expected is equals to out, and further, if in is equals to expected, then out is
   * successfully optimized to be identical to in, i.e. that "in" is simply returned.
   */
  private void assertEqualsSame(String expected, String in, String out) {