*
   * @since 20.0
   */
  public static void throwIfUnchecked(Throwable throwable) {
    checkNotNull(throwable);
    if (throwable instanceof RuntimeException) {
      throw (RuntimeException) throwable;
    }
    if (throwable instanceof Error) {
      throw (Error) throwable;
    }
  }

  /**
   * Propagates {@code throwable} exactly as-is, if and only if it is an instance of {@link

    Throwable throwable = thrown;

    // close closeables in LIFO order
    while (!stack.isEmpty()) {
      Closeable closeable = stack.removeFirst();
      try {
        closeable.close();
      } catch (Throwable e) {
        if (throwable == null) {
          throwable = e;
        } else {
          suppressor.suppress(closeable, throwable, e);
        }
      }
    }

import static com.google.common.base.Throwables.getCausalChain;
import static com.google.common.base.Throwables.getCauseAs;
import static com.google.common.base.Throwables.getRootCause;
import static com.google.common.base.Throwables.getStackTraceAsString;
import static com.google.common.base.Throwables.lazyStackTrace;
import static com.google.common.base.Throwables.lazyStackTraceIsLazy;

    @Override
    public void suppress(Closeable closeable, Throwable thrown, Throwable suppressed) {
      suppressions.add(new Suppression(closeable, thrown, suppressed));
    }
  }

  /** Record of a call to suppress. */
  private static class Suppression {
    private final Closeable closeable;
    private final Throwable thrown;
    private final Throwable suppressed;

import static com.google.common.base.Throwables.getCausalChain;
import static com.google.common.base.Throwables.getCauseAs;
import static com.google.common.base.Throwables.getRootCause;
import static com.google.common.base.Throwables.getStackTraceAsString;
import static com.google.common.base.Throwables.lazyStackTrace;
import static com.google.common.base.Throwables.lazyStackTraceIsLazy;

        log.fatal(message.toString());
    }

    /**
     * ログを出力します。
     *
     * @param throwable
     *            例外。{@literal null}であってはいけません
     */
    public void log(final Throwable throwable) {
        assertArgumentNotNull("throwable", throwable);

        error(throwable.getMessage(), throwable);
    }

    /**
     * ログを出力します。
     *
     * @param messageCode

  }

  @CanIgnoreReturnValue
  protected boolean setException(Throwable throwable) {
    checkNotNull(throwable);
    if (!state.permitsPublicUserToTransitionTo(State.FAILURE)) {
      return false;
    }

    forceSetException(throwable);
    return true;
  }

  private void forceSetException(Throwable throwable) {
    this.throwable = throwable;
    this.state = State.FAILURE;
    notifyAndClearListeners();

    @Override
    public void suppress(Closeable closeable, Throwable thrown, Throwable suppressed) {
      suppressions.add(new Suppression(closeable, thrown, suppressed));
    }
  }

  /** Record of a call to suppress. */
  private static class Suppression {
    private final Closeable closeable;
    private final Throwable thrown;
    private final Throwable suppressed;

    Throwable throwable = thrown;

    // close closeables in LIFO order
    while (!stack.isEmpty()) {
      Closeable closeable = stack.removeFirst();
      try {
        closeable.close();
      } catch (Throwable e) {
        if (throwable == null) {
          throwable = e;
        } else {
          suppressor.suppress(closeable, throwable, e);
        }
      }
    }

        val addresses = Dns.SYSTEM.lookup(hostname)
        listOf(addresses[0])
      }

    private operator fun Throwable?.plus(throwable: Throwable): Throwable {
      if (this != null) {
        addSuppressed(throwable)
        return this
      }
      return throwable
    }
  }