getByte（）替代使用int数据类型

Question

我想创建一个qr代码来传输这样的数据：

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import javax.imageio.ImageIO;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatReader;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.NotFoundException;
import com.google.zxing.Result;
import com.google.zxing.WriterException;
import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;

public class QRCode {
    static int a = 0;
    public static void main(String[] args) throws WriterException,
                                           IOException,NotFoundException
    {
        int qrCodeData = a;
        String filePath = "C://Users/Tommy/QRCode.png";
        String charset = "UTF-8"; // or "ISO-8859-1"
        Map<EncodeHintType, ErrorCorrectionLevel> hintMap = new HashMap<EncodeHintType,ErrorCorrectionLevel>();
        hintMap.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.L);

        createQRCode(qrCodeData, filePath, charset, hintMap, 200, 200);
        System.out.println("QR Code image created successfully!");

        System.out.println("Data read from QR Code: "
        + readQRCode(filePath, charset, hintMap));

    }

    public static void createQRCode(final int qrCodeData, String filePath,
                                      String charset, Map hintMap, 
                                      final int qrCodeheight, final int qrCodewidth)
                                      throws WriterException, IOException
    {
        BitMatrix matrix = new MultiFormatWriter().encode(
        new String(qrCodeData.getBytes(charset), charset),
        BarcodeFormat.QR_CODE, qrCodewidth, qrCodeheight);
        MatrixToImageWriter.writeToFile(matrix, filePath.substring(filePath.lastIndexOf('.') + 1), new File(filePath));
    }

    public static String readQRCode(String filePath, String charset, Map hintMap)
      throws FileNotFoundException, IOException, NotFoundException
    {
        BinaryBitmap binaryBitmap = new BinaryBitmap(new HybridBinarizer(
                                      new BufferedImageLuminanceSource(
                                      ImageIO.read(new FileInputStream(filePath)))));
        Result qrCodeResult = new MultiFormatReader().decode(binaryBitmap);
        return qrCodeResult.getText();
    }
}

但是在代码中，我使用的是getBytes（），因为我使用的是整数值而不是字符串值，所以如何更改这个以便我可以使用int数据类型？