sslSocket: SSLSocket,
    hostname: String?,
    protocols: List<Protocol>,
  ) {
    getDelegate(sslSocket)?.configureTlsExtensions(sslSocket, hostname, protocols)
  }

  override fun getSelectedProtocol(sslSocket: SSLSocket): String? = getDelegate(sslSocket)?.getSelectedProtocol(sslSocket)

  @Synchronized private fun getDelegate(sslSocket: SSLSocket): SocketAdapter? {

    stream.defaultReadObject();
    keyTypeOrObjectUnderJ2cl = (Class<K>) requireNonNull(stream.readObject());
    valueTypeOrObjectUnderJ2cl = (Class<V>) requireNonNull(stream.readObject());
    setDelegates(
        new EnumMap<K, V>(keyTypeOrObjectUnderJ2cl), new EnumMap<V, K>(valueTypeOrObjectUnderJ2cl));
    Serialization.populateMap(this, stream);
  }

     * the number of entries in the map, as that makes it easy for hostile inputs to trigger lots of
     * allocation—not that any program should be deserializing hostile inputs to begin with!)
     */
    setDelegates(new EnumMap<K, V>(keyTypeOrObjectUnderJ2cl), new HashMap<V, K>());
    Serialization.populateMap(this, stream);
  }

  @GwtIncompatible @J2ktIncompatible private static final long serialVersionUID = 0;