majorVersion >= 9
        } else {
          try {
            // also present on JDK8 after build 252.
            SSLSocket::class.java.getMethod("getApplicationProtocol")
            true
          } catch (nsme: NoSuchMethodException) {
            false
          }
        }
    }

    fun buildIfSupported(): Jdk9Platform? = if (isAvailable) Jdk9Platform() else null
  }