*
   * <p><b>Warning: do not depend</b> on the behavior of this method.
   *
   * <p>Historically, {@code Predicate} instances in this library have implemented this method to
   * recognize certain cases where distinct {@code Predicate} instances would in fact behave
   * identically. However, as code migrates to {@code java.util.function}, that behavior will
   * disappear. It is best not to depend on it.
   */
  @Override

   *
   * <p><b>Warning: do not depend</b> on the behavior of this method.
   *
   * <p>Historically, {@code Supplier} instances in this library have implemented this method to
   * recognize certain cases where distinct {@code Supplier} instances would in fact behave
   * identically. However, as code migrates to {@code java.util.function}, that behavior will
   * disappear. It is best not to depend on it.
   */
  @Override

    arraycopy(second, 0, result, first.length, second.length);
    return result;
  }

  /**
   * Returns a new array that prepends {@code element} to {@code array}.
   *
   * @param element the element to prepend to the front of {@code array}
   * @param array the array of elements to append
   * @return an array whose size is one larger than {@code array}, with {@code element} occupying

   *
   * @throws IllegalStateException if the response is closed.
   * @throws IOException if the trailers cannot be loaded, such as if the network connection is
   *     dropped.
   */
  @Throws(IOException::class)
  fun trailers(): Headers = trailersSource.get()

  /**
   * Returns the trailers after the HTTP response, if they are available to read immediately. Unlike

   *
   * <p><b>Warning: do not depend</b> on the behavior of this method.
   *
   * <p>Historically, {@code Supplier} instances in this library have implemented this method to
   * recognize certain cases where distinct {@code Supplier} instances would in fact behave
   * identically. However, as code migrates to {@code java.util.function}, that behavior will
   * disappear. It is best not to depend on it.
   */
  @Override

   * whether nulls were to be permitted or forbidden, but presumably the eventual fix will be to
   * permit them, as it seems more likely that code would depend on that behavior than on the other.
   * Thus, we say the bug is in add(), which fails to support null.
   */
  @J2ktIncompatible
  @GwtIncompatible // reflection
  public static Method getAddNullSupportedMethod() {

   * whether nulls were to be permitted or forbidden, but presumably the eventual fix will be to
   * permit them, as it seems more likely that code would depend on that behavior than on the other.
   * Thus, we say the bug is in add(), which fails to support null.
   */
  @J2ktIncompatible
  @GwtIncompatible // reflection
  public static Method getAddNullSupportedMethod() {

   * whether nulls were to be permitted or forbidden, but presumably the eventual fix will be to
   * permit them, as it seems more likely that code would depend on that behavior than on the other.
   * Thus, we say the bug is in set(), which fails to support null.
   */
  @J2ktIncompatible
  @GwtIncompatible // reflection
  public static Method getSetNullSupportedMethod() {

 * comparator is not consistent with {@code equals}.
 *
 * <p>The {@code standard} methods are not guaranteed to be thread-safe, even when all of the
 * methods that they depend on are thread-safe.
 *
 * @author Mike Bostock
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible
public abstract class ForwardingMapEntry<K extends @Nullable Object, V extends @Nullable Object>

   * requests on the same socket, and server-push. HTTP/1.1 semantics are layered on SPDY/3.
   *
   * Current versions of OkHttp do not support this protocol.
   */
  @Deprecated("OkHttp has dropped support for SPDY. Prefer {@link #HTTP_2}.")
  SPDY_3("spdy/3.1"),

  /**
   * The IETF's binary-framed protocol that includes header compression, multiplexing multiple