val tag: Long,
  /** Encode and decode the value once tags are handled. */
  private val codec: Codec<T>,
  /** True if the default value should be used if this value is absent during decoding. */
  val isOptional: Boolean = false,
  /** The value to return if this value is absent. Undefined unless this is optional. */
  val defaultValue: T? = null,

        align(2);
        final int val = Encdec.dec_uint16le(buf, index);
        advance(2);
        return val;
    }

    /**
     * Encodes a long integer (4 bytes) in NDR format.
     *
     * @param l the long integer value to encode
     */
    public void enc_ndr_long(final int l) {
        align(4);
        Encdec.enc_uint32le(l, buf, index);
        advance(4);
    }

        Arrays.fill(dst, (byte) 0x55);

        // Act
        int written = enc.encode(dst, dstIndex);

        // Assert: reported written bytes matches size() and requested len.
        assertEquals(len, enc.size(), "size() must equal provided length");
        assertEquals(len, written, "encode() must return number of bytes written");

        // Assert: copied region equals the source slice.

        // When - Decode
        FileBasicInfo decodedInfo = new FileBasicInfo();
        int bytesDecoded = decodedInfo.decode(buffer, 0, bytesEncoded);

        // Then
        assertEquals(40, bytesEncoded);
        assertEquals(36, bytesDecoded); // decode returns 36, encode returns 40
        assertEquals(originalInfo.getCreateTime(), decodedInfo.getCreateTime());

        @Override
        public void encode(NdrBuffer _dst) throws NdrException {
            _dst.align(4);
            _dst.enc_ndr_referent(netname, 1);

            if (netname != null) {
                _dst = _dst.deferred;
                _dst.enc_ndr_string(netname);

            }
        }

        @Override
        public void decode(NdrBuffer _src) throws NdrException {
            _src.align(4);

      (
        codePoint == '\t'.code ||
          codePoint == '\n'.code ||
          codePoint == '\u000c'.code ||
          codePoint == '\r'.code
      )
    ) {
      // Skip this character.
    } else if (codePoint == ' '.code && encodeSet === FORM_ENCODE_SET) {
      // Encode ' ' as '+'.
      writeUtf8("+")
    } else if (codePoint == '+'.code && plusIsSpace) {

        // Given
        request.setSessionBinding(true);
        byte[] buffer = new byte[512];
        int headerStart = 50;

        // Encode the full message to set headerStart
        request.encode(buffer, headerStart);

        // Then - verify the body was written correctly
        int bodyOffset = headerStart + Smb2Constants.SMB2_HEADER_LENGTH;

    assertFailsWith<ProtocolException> {
      derReader.read("test") {}
    }.also { expected ->
      assertThat(expected.message)
        .isEqualTo("length encoded with more than 8 bytes is not supported")
    }
  }

  @Test fun `encode tag and length`() {
    val buffer = Buffer()
    val derWriter = DerWriter(buffer)

    derWriter.write("test", tagClass = DerHeader.TAG_CLASS_UNIVERSAL, tag = 30L) {

        align(2);
        final int val = Encdec.dec_uint16le(this.buf, this.index);
        advance(2);
        return val;
    }

    /**
     * Encodes a long integer (4 bytes) in NDR format.
     *
     * @param l the long integer value to encode
     */
    public void enc_ndr_long(final int l) {
        align(4);
        Encdec.enc_uint32le(l, this.buf, this.index);
        advance(4);

func TestEncodeDecodemetacache(t *testing.T) {
	v := metacache{}
	var buf bytes.Buffer
	msgp.Encode(&buf, &v)

	m := v.Msgsize()
	if buf.Len() > m {
		t.Log("WARNING: TestEncodeDecodemetacache Msgsize() is inaccurate")
	}

	vn := metacache{}
	err := msgp.Decode(&buf, &vn)
	if err != nil {
		t.Error(err)
	}

	buf.Reset()
	msgp.Encode(&buf, &v)
	err = msgp.NewReader(&buf).Skip()
	if err != nil {
		t.Error(err)
	}