public BitMatrix encode(String contents, BarcodeFormat format, int width, int height, Map<EncodeHintType, ?> hints) throws WriterException {
    Object writer;
    switch(format.ordinal()) {
    case 1:
      writer = new AztecWriter();
      break;
    case 2:
      writer = new CodaBarWriter();
      break;
    case 3:
      writer = new Code39Writer();
      break;
    case 4:
    case 10:
    case 13:
    case 14:
    default:
      throw new IllegalArgumentException("No encoder available for format " + format);
    case 5:
      writer = new Code128Writer();
      break;
    case 6:
      writer = new DataMatrixWriter();
      break;
    case 7:
      writer = new EAN8Writer();
      break;
    case 8:
      writer = new EAN13Writer();
      break;
    case 9:
      writer = new ITFWriter();
      break;
    case 11:
      writer = new PDF417Writer();
      break;
    case 12:
      writer = new QRCodeWriter();
      break;
    case 15:
      writer = new UPCAWriter();
      break;
    case 16:
      writer = new UPCEWriter();
    }
    return ((Writer)writer).encode(contents, format, width, height, hints);
  }

public enum BarcodeFormat {
  AZTEC,
  CODABAR,
  CODE_39,
  CODE_93,
  CODE_128,
  DATA_MATRIX,
  EAN_8,
  EAN_13,
  ITF,
  MAXICODE,
  PDF_417,
  QR_CODE,
  RSS_14,
  RSS_EXPANDED,
  UPC_A,
  UPC_E,
  UPC_EAN_EXTENSION;

  private BarcodeFormat() {
  }
}

    switch(format.ordinal()) {
    case 1:
      writer = new AztecWriter();
      break;
    case 2:
      writer = new CodaBarWriter();
      break;
    case 3:
      writer = new Code39Writer();
      break;
    ...............

public interface Writer {
  BitMatrix encode(String var1, BarcodeFormat var2, int var3, int var4) throws WriterException;

  BitMatrix encode(String var1, BarcodeFormat var2, int var3, int var4, Map<EncodeHintType, ?> var5) throws WriterException;
}

  private static Configuration getDefaultConfiguration () {
      if (defaultImpl == null) {
        defaultImpl = new DefaultConfiguration();
        try {
          String className = getString("webwork.configuration");
          if (!className.equals(defaultImpl.getClass().getName())) {
            try {
              defaultImpl = (Configuration) ObjectFactory.getObjectFactory().buildBean(Thread.currentThread().getContextClassLoader().loadClass(className));
            } catch (Exception e) {
              LOG.error("Could not instantiate configuration", e);
            }
          }
          return defaultImpl;
        } catch (IllegalArgumentException localIllegalArgumentException) {
        }
      }
    }