versionMap.put(version, index++);
out.writeStringNull(version.toString());
}
// write mapping data
out.writeInt(ftm.entrySet().size());
for (Map.Entry<Pair<Integer, UnityVersion>, TypeField> entry : ftm.entrySet()) {
index = fieldNodeMap.get(entry.getValue());
Pair<Integer, UnityVersion> fieldNodeKey = entry.getKey();