条形码和二维码编码解码

public class ZxingHandler {

   /**
    * 条形码编码
    * 
    * @param contents
    * @param width
    * @param height
    * @param imgPath
    */
   public static void encode(String contents, int width, int height, String imgPath) {
      int codeWidth = 3 + // start guard
            (7 * 6) + // left bars
            5 + // middle guard
            (7 * 6) + // right bars
            3; // end guard
      codeWidth = Math.max(codeWidth, width);
      try {
         BitMatrix bitMatrix = new MultiFormatWriter().encode(contents,
               BarcodeFormat.EAN_13, codeWidth, height, null);

         MatrixToImageWriter
               .writeToFile(bitMatrix, "png", new File(imgPath));

      } catch (Exception e) {
         e.printStackTrace();
      }
   }

   /**
    * 条形码解码
    * 
    * @param imgPath
    * @return String
    */
   public static String decode(String imgPath) {
      BufferedImage image = null;
      Result result = null;
      try {
         image = ImageIO.read(new File(imgPath));
         if (image == null) {
            System.out.println("the decode image may be not exit.");
         }
         LuminanceSource source = new BufferedImageLuminanceSource(image);
         BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));

         result = new MultiFormatReader().decode(bitmap, null);
         return result.getText();
      } catch (Exception e) {
         e.printStackTrace();
      }
      return null;
   }
   
   /**
    * 二维码编码
    * 
    * @param contents
    * @param width
    * @param height
    * @param imgPath
    */
   public static void encode2(String contents, int width, int height, String imgPath) {
      Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
      // 指定纠错等级
      hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.L);
      // 指定编码格式
      hints.put(EncodeHintType.CHARACTER_SET, "GBK");
      try {
         BitMatrix bitMatrix = new MultiFormatWriter().encode(contents,
               BarcodeFormat.QR_CODE, width, height, hints);

         MatrixToImageWriter
               .writeToFile(bitMatrix, "png", new File(imgPath));

      } catch (Exception e) {
         e.printStackTrace();
      }
   }

   /**
    * 二维码解码
    * 
    * @param imgPath
    * @return String
    */
   public static String decode2(String imgPath) {
      BufferedImage image = null;
      Result result = null;
      try {
         image = ImageIO.read(new File(imgPath));
         if (image == null) {
            System.out.println("the decode image may be not exit.");
         }
         LuminanceSource source = new BufferedImageLuminanceSource(image);
         BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));

         Hashtable<DecodeHintType, Object> hints = new Hashtable<DecodeHintType, Object>();
         hints.put(DecodeHintType.CHARACTER_SET, "GBK");

         result = new MultiFormatReader().decode(bitmap, hints);
         return result.getText();
      } catch (Exception e) {
         e.printStackTrace();
      }
      return null;
   }

   /**
    * @param args
    */
   public static void main(String[] args) {

      // 条形码
      String imgPath = "target\\zxing_EAN13.png";
      String contents = "6923450657713";
      int width = 105, height = 50;
      
      ZxingHandler.encode(contents, width, height, imgPath);
      System.out.println("finished zxing EAN-13 encode.");

      String decodeContent = ZxingHandler.decode(imgPath);
      System.out.println("解码内容如下：" + decodeContent);
      System.out.println("finished zxing EAN-13 decode.");
      
      // 二维码
      String imgPath2 = "target\\zxing.png";
      String contents2 = "Hello Gem, welcome to Zxing!"
            + "\nBlog [ http://thinkgem.iteye.com ]"
            + "\nEMail [ thinkgem@163.com ]";
      int width2 = 300, height2 = 300;

      ZxingHandler.encode2(contents2, width2, height2, imgPath2);
      System.out.println("finished zxing encode.");

      String decodeContent2 = ZxingHandler.decode2(imgPath2);
      System.out.println("解码内容如下：" + decodeContent2);
      System.out.println("finished zxing decode.");
      
   }
    
}