/**
* Prepare to read a SAM text file.
* @param stream Need not be buffered, as this class provides buffered reading.
*/
SAMTextReader2(final InputStream stream, final SAMFileReader.ValidationStringency validationStringency, final SAMRecordFactory factory, SAMFileHeader header) {
mReader = new BufferedLineReader(stream);
this.validationStringency = validationStringency;
this.samRecordFactory = factory;
this.mFileHeader = header;
advanceLine();
// readHeader();