public static boolean isHomozygousAlt(VcfRecord rec,int sample){
  final int[] gtArray=getValidGt(rec,sample);
  return isHomozygousAlt(gtArray);
}

public static boolean isHomozygousAlt ( VcfRecord rec , int sample ) { final int [ ] gtArray = getValidGt ( rec , sample ) ; return isHomozygousAlt ( gtArray ) ; }
tests if the given sample genotype in a record is homozygous alt .
