@Override
 public VariantContext next() {
   try {
     final VariantContext vc = codec.decode(nextSource());
     return vc == null ? null : vc.fullyDecode(header, false);
   } catch (IOException e) {
     throw new RuntimeException(e);
   }
 }
  private static void makeEmpiricalTests() throws IOException {
    if (ENABLE_SOURCE_VCF_TESTS) {
      for (final File file : testSourceVCFs) {
        VCFCodec codec = new VCFCodec();
        VariantContextContainer x = readAllVCs(file, codec);
        List<VariantContext> fullyDecoded = new ArrayList<VariantContext>();

        for (final VariantContext raw : x.getVCs()) {
          if (raw != null) fullyDecoded.add(raw.fullyDecode(x.getHeader(), false));
        }

        TEST_DATAs.add(new VariantContextTestData(x.getHeader(), fullyDecoded));
      }
    }
  }