{ // try crai:
List<CramIndex.Entry> entries = getCraiEntries(cramFile,
cramHeader, cramFileInputStream, location);
if (entries != null) {
try {
Entry leftmost = CramIndex.getLeftmost(entries);
cramFileInputStream.seek(leftmost.containerStartOffset);
c = ReadWrite.readContainerHeader(cramFileInputStream);
if (c == null) return null ;
if (c.alignmentStart + c.alignmentSpan > location.start) {
cramFileInputStream.seek(leftmost.containerStartOffset);