public BitCodec<List<ReadFeature>> buildCodec(CramHeader header,
CompressionHeader compression,
SequenceBaseProvider referenceBaseProvider,
DefaultMutableTreeNode parent) throws CramException {
ReadFeatureCodec codec = new ReadFeatureCodec();
DefaultMutableTreeNode node = buildNode(codec, "Variations codec");
parent.add(node);
codec.inReadPosCodec = register(
bitCodecFactory.buildLongCodec(compression