fun readHeaders() {
        while (!source.exhausted()) {
          val b = source.readByte() and 0xff
          when {
            b == 0x80 -> {
              // 10000000
              throw IOException("index == 0")
            }

            b and 0x80 == 0x80 -> {
              // 1NNNNNNN
              val index = readInt(b, PREFIX_7_BITS)
              readIndexedHeader(index - 1)
            }

          return null;
        }

        @Override
        public Range<Comparable<?>> span() {
          throw new NoSuchElementException();
        }

        @Override
        public void put(Range<Comparable<?>> range, Object value) {
          checkNotNull(range);
          throw new IllegalArgumentException(
              "Cannot insert range " + range + " into an empty subRangeMap");
        }

        public DateFormat next() {
            if (!hasNext()) {
                throw new NoSuchElementException();
            }
            final int style = STYLES[index++];
            return DateFormat.getDateInstance(style, locale);
        }

        @Override
        public void remove() {
            throw new ClUnsupportedOperationException("remove");
        }

    }

    /**

import static org.junit.jupiter.api.Assertions.assertThrows;
import static org.mockito.ArgumentMatchers.eq;
import static org.mockito.ArgumentMatchers.isNull;
import static org.mockito.Mockito.doThrow;
import static org.mockito.Mockito.never;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;

import org.junit.jupiter.api.DisplayName;

    if (assets == null) {
      if (Build.FINGERPRINT == null) {
        throw IOException(
          "Platform applicationContext not initialized. " +
            "Possibly running Android unit test without Robolectric. " +
            "Android tests should run with Robolectric " +
            "and call OkHttp.initialize before test",
        )
      } else {
        throw IOException(
          "Platform applicationContext not initialized. " +

                        writer.write(metadata);
                    }
                });
            } catch (final SsoMessageException e) {
                throw e;
            } catch (final Exception e) {
                throw new SsoMessageException(
                        messages -> messages.addErrorsFailedToProcessSsoRequest(UserMessages.GLOBAL_PROPERTY_KEY, e.getMessage()),

    return certificates.single() as X509Certificate
  } catch (nsee: NoSuchElementException) {
    throw IllegalArgumentException("failed to decode certificate", nsee)
  } catch (iae: IllegalArgumentException) {
    throw IllegalArgumentException("failed to decode certificate", iae)
  } catch (e: GeneralSecurityException) {
    throw IllegalArgumentException("failed to decode certificate", e)
  }
}

/**

   *
   * @throws UnsupportedOperationException always
   * @deprecated Unsupported operation.
   */
  @CanIgnoreReturnValue
  @Deprecated
  @Override
  @DoNotCall("Always throws UnsupportedOperationException")
  public final @Nullable V putIfAbsent(K key, V value) {
    throw new UnsupportedOperationException();
  }

  /**

   */
  @CanIgnoreReturnValue
  @Deprecated
  @Override
  @DoNotCall("Always throws UnsupportedOperationException")
  public @Nullable B put(TypeToken<? extends @NonNull B> key, @ParametricNullness B value) {
    throw new UnsupportedOperationException("Please use putInstance() instead.");
  }

  /**
   * Not supported. Use {@link #putInstance} instead.
   *
   * @deprecated unsupported operation

    private static LogStream log = LogStream.getInstance();

    /**
     * This is really just for {@link jcifs.smb1.UniAddress}. It does
     * not throw an {@link java.net.UnknownHostException} because this
     * is queried frequently and exceptions would be rather costly to
     * throw on a regular basis here.
     *
     * @param host the hostname to resolve
     * @return the resolved NbtAddress or null if not found
     */