// Test with binary data
        final byte[] binaryData = new byte[] { 0, 1, 2, 3, 127, (byte) 128, (byte) 255 };
        final String binaryEncoded = Base64Util.encode(binaryData);
        final byte[] binaryDecoded = Base64Util.decode(binaryEncoded);
        assertEquals("Binary data length should match", binaryData.length, binaryDecoded.length);
        for (int i = 0; i < binaryData.length; i++) {

    val length = 5
    val payload: ByteString = (binaryData(length))
    serverWriter.writeMessageFrame(OPCODE_TEXT, payload)
    assertData("8105")
    assertData(payload)
  }

  @Test fun serverLargeBufferedPayloadWrittenAsOneFrame() {
    val length = 12345
    val payload: ByteString = (binaryData(length))
    serverWriter.writeMessageFrame(OPCODE_TEXT, payload)
    assertData("817e")

        // Test with binary content
        byte[] binaryData = new byte[] { 0x00, 0x01, 0x02, (byte) 0xFF, (byte) 0xFE, (byte) 0xFD };

        ResponseData responseData = new ResponseData() {
            @Override
            public InputStream getResponseBody() {
                return new ByteArrayInputStream(binaryData);
            }

            @Override
            public String getUrl() {