if (writeKind == WriteKind.BYTE_BY_BYTE) {
            for (i in 0 until n) {
              sink.writeByte('x'.code)
            }
          } else {
            val buf = ByteArray(if (writeKind == WriteKind.SMALL_BUFFERS) 256 else 64 * 1024)
            Arrays.fill(buf, 'x'.code.toByte())
            var i = 0
            while (i < n) {
              sink.write(buf, 0, Math.min(buf.size, n - i))

        .Builder()
        .url(server.url("/"))
        .head()
        .build()
    val response = client.newCall(headRequest).execute()
    assertThat(response.code).isEqualTo(200)
    assertArrayEquals(ByteArray(0), response.body.bytes())
    val getRequest = Request(server.url("/"))
    executeSynchronously(getRequest)
      .assertCode(200)
      .assertBody("abc")