private void initializeVcfWriter() { final List<String> inputNames = Arrays.asList(validation.getName()); // setup the header fields Set<VCFHeaderLine> hInfo = new HashSet<VCFHeaderLine>(); hInfo.addAll(VCFUtils.getHeaderFields(getToolkit(), inputNames)); hInfo.add( new VCFFilterHeaderLine( "bootstrap", "This site used for genotype bootstrapping with ProduceBeagleInputWalker")); bootstrapVCFOutput.writeHeader( new VCFHeader(hInfo, SampleUtils.getUniqueSamplesFromRods(getToolkit(), inputNames))); }