reader = new SAMFileReader(bamFile);
reader.setValidationStringency(ValidationStringency.SILENT);
reader.enableIndexCaching(true);
index = reader.getIndex();
reader.queryOverlapping(contigName,1,reader.getFileHeader().getSequence(contigName).getSequenceLength()).close();
int numBins = 0;
int numChunks = 0;
int numLinearIndexEntries = 0;