protected void decode()

in folsom/src/main/java/com/spotify/folsom/client/binary/BinaryMemcacheDecoder.java [37:111]
62 lines of code
11 McCabe index (conditional complexity)

  protected void decode(final ChannelHandlerContext ctx, final ByteBuf buf, final List<Object> out)
      throws Exception {
    for (int i = 0; i < BATCH_SIZE; i++) {
      if (buf.readableBytes() < 24) {
        return;
      }

      buf.markReaderIndex();

      final int magicNumber = buf.readUnsignedByte(); // byte 0
      if (magicNumber != 0x81) {
        throw fail(buf, String.format("Invalid magic number: 0x%2x", magicNumber));
      }

      final OpCode opcode = OpCode.of(buf.readByte()); // byte 1
      final int keyLength = buf.readUnsignedShort(); // byte 2-3
      final int extrasLength = buf.readUnsignedByte(); // byte 4
      buf.skipBytes(1);
      final int statusCode = buf.readUnsignedShort(); // byte 6-7

      final MemcacheStatus status = MemcacheStatus.fromInt(statusCode);

      final int totalLength = buf.readInt(); // byte 8-11
      final int opaque = buf.readInt();

      final long cas = buf.readLong();

      if (buf.readableBytes() < totalLength) {
        buf.resetReaderIndex();
        return;
      }

      int flags = 0;
      if (extrasLength >= 4) {
        flags = buf.readInt();
        final int extrasBytesLeft = extrasLength - 4; // 4 bytes for the flags
        buf.skipBytes(extrasBytesLeft);
      }

      byte[] keyBytes;
      if (keyLength == 0) {
        keyBytes = NO_BYTES;
      } else {
        keyBytes = new byte[keyLength];
      }
      buf.readBytes(keyBytes);

      final int valueLength = totalLength - keyLength - extrasLength;
      byte[] valueBytes;
      if (valueLength == 0) {
        valueBytes = NO_BYTES;
      } else {
        valueBytes = new byte[valueLength];
      }

      buf.readBytes(valueBytes);

      if (opcode == OpCode.STAT) {
        boolean endPacket = keyLength == 0;
        if (endPacket) {
          out.add(replies);
          replies = new BinaryResponse();
        } else {
          // Skip end packet
          replies.add(new ResponsePacket(opcode, status, opaque, cas, flags, keyBytes, valueBytes));
        }
      } else {
        replies.add(new ResponsePacket(opcode, status, opaque, cas, flags, keyBytes, valueBytes));
        if ((opaque & 0xFF) == 0) {
          out.add(replies);
          replies = new BinaryResponse();
        }
      }
    }
  }