* @return Next covered locus context in the shard.
* @throw NoSuchElementException if no such element exists.
*/
public AlignmentContext next() {
if ( DEBUG ) System.out.printf("In RodLocusView.next()...%n");
RODRecordList datum = rodQueue.next();
if ( DEBUG ) System.out.printf("In RodLocusView.next(); datum = %s...%n", datum.getLocation());
if ( DEBUG ) System.out.printf("In RodLocusView.next(): creating tracker...%n");
allTracksHere = getSpanningTracks(datum);
GenomeLoc rodSite = datum.getLocation();
GenomeLoc site = genomeLocParser.createGenomeLoc( rodSite.getContig(), rodSite.getStart(), rodSite.getStart());
if ( DEBUG ) System.out.printf("rodLocusView.next() is at %s%n", site);
// calculate the number of skipped bases, and update lastLoc so we can do that again in the next()