/**
   * Decodes value from a given byte array to the object according to the flags given.
   *
   * @param flags Flags.
   * @param bytes Byte array to decode.
   * @return Decoded value.
   * @throws GridException If deserialization failed.
   */
  private Object decodeObj(short flags, byte[] bytes) throws GridException {
    assert bytes != null;

    if ((flags & SERIALIZED_FLAG) != 0)
      return jdkMarshaller.unmarshal(new ByteArrayInputStream(bytes), null);

    int masked = flags & 0xff00;

    switch (masked) {
      case BOOLEAN_FLAG:
        return bytes[0] == '1';
      case INT_FLAG:
        return U.bytesToInt(bytes, 0);
      case LONG_FLAG:
        return U.bytesToLong(bytes, 0);
      case DATE_FLAG:
        return new Date(U.bytesToLong(bytes, 0));
      case BYTE_FLAG:
        return bytes[0];
      case FLOAT_FLAG:
        return Float.intBitsToFloat(U.bytesToInt(bytes, 0));
      case DOUBLE_FLAG:
        return Double.longBitsToDouble(U.bytesToLong(bytes, 0));
      case BYTE_ARR_FLAG:
        return bytes;
      default:
        return new String(bytes);
    }
  }
  /**
   * Validates incoming packet and deserializes all fields that need to be deserialized.
   *
   * @param ses Session on which packet is being parsed.
   * @param req Raw packet.
   * @return Same packet with fields deserialized.
   * @throws IOException If parsing failed.
   * @throws GridException If deserialization failed.
   */
  private GridClientMessage assemble(GridNioSession ses, GridTcpRestPacket req)
      throws IOException, GridException {
    byte[] extras = req.extras();

    // First, decode key and value, if any
    if (req.key() != null || req.value() != null) {
      short keyFlags = 0;
      short valFlags = 0;

      if (req.hasFlags()) {
        if (extras == null || extras.length < FLAGS_LENGTH)
          throw new IOException(
              "Failed to parse incoming packet (flags required for command) [ses="
                  + ses
                  + ", opCode="
                  + Integer.toHexString(req.operationCode() & 0xFF)
                  + ']');

        keyFlags = U.bytesToShort(extras, 0);
        valFlags = U.bytesToShort(extras, 2);
      }

      if (req.key() != null) {
        assert req.key() instanceof byte[];

        byte[] rawKey = (byte[]) req.key();

        // Only values can be hessian-encoded.
        req.key(decodeObj(keyFlags, rawKey));
      }

      if (req.value() != null) {
        assert req.value() instanceof byte[];

        byte[] rawVal = (byte[]) req.value();

        req.value(decodeObj(valFlags, rawVal));
      }
    }

    if (req.hasExpiration()) {
      if (extras == null || extras.length < 8)
        throw new IOException(
            "Failed to parse incoming packet (expiration value required for command) [ses="
                + ses
                + ", opCode="
                + Integer.toHexString(req.operationCode() & 0xFF)
                + ']');

      req.expiration(U.bytesToInt(extras, 4) & 0xFFFFFFFFL);
    }

    if (req.hasInitial()) {
      if (extras == null || extras.length < 16)
        throw new IOException(
            "Failed to parse incoming packet (initial value required for command) [ses="
                + ses
                + ", opCode="
                + Integer.toHexString(req.operationCode() & 0xFF)
                + ']');

      req.initial(U.bytesToLong(extras, 8));
    }

    if (req.hasDelta()) {
      if (extras == null || extras.length < 8)
        throw new IOException(
            "Failed to parse incoming packet (delta value required for command) [ses="
                + ses
                + ", opCode="
                + Integer.toHexString(req.operationCode() & 0xFF)
                + ']');

      req.delta(U.bytesToLong(extras, 0));
    }

    if (extras != null) {
      // Clients that include cache name must always include flags.
      int length = 4;

      if (req.hasExpiration()) length += 4;

      if (req.hasDelta()) length += 8;

      if (req.hasInitial()) length += 8;

      if (extras.length - length > 0) {
        byte[] cacheName = new byte[extras.length - length];

        System.arraycopy(extras, length, cacheName, 0, extras.length - length);

        req.cacheName(new String(cacheName));
      }
    }

    return req;
  }