* @param walker walker to interrogate.
* @param dataProvider Data which which to drive the locus view.
* @return A view of the locus data, where one iteration of the locus view maps to one iteration of the traversal.
*/
private LocusView getLocusView( Walker<M,T> walker, LocusShardDataProvider dataProvider ) {
final DataSource dataSource = WalkerManager.getWalkerDataSource(walker);
if( dataSource == DataSource.READS )
return new CoveredLocusView(dataProvider);
else if( dataSource == DataSource.REFERENCE ) //|| ! GenomeAnalysisEngine.instance.getArguments().enableRodWalkers )
return new AllLocusView(dataProvider);
else if( dataSource == DataSource.REFERENCE_ORDERED_DATA )