version = CodecUtil.checkHeader(indexStream, codecNameIdx, VERSION_START, VERSION_CURRENT);
assert CodecUtil.headerLength(codecNameIdx) == indexStream.getFilePointer();
indexReader = new CompressingStoredFieldsIndexReader(indexStream, si);
if (version >= VERSION_CHECKSUM) {
indexStream.readVLong(); // the end of the data file
CodecUtil.checkFooter(indexStream);
} else {
CodecUtil.checkEOF(indexStream);
}
indexStream.close();