Java实现二维码QRCode的编码和解码与示例解析

package michael.qrcode;  import java.awt.Color; import java.awt.Graphics2D; import java.awt.image.BufferedImage; import java.io.File;  import javax.imageio.ImageIO;  import com.swetake.util.Qrcode;  /** * 二维码生成器 * @blog http://sjsky.iteye.com * @author Michael */ public class QRCodeEncoderHandler {   /** * 生成二维码(QRCode)图片 * @param content * @param imgPath */  public void encoderQRCode(String content, String imgPath) {  try {   Qrcode qrcodeHandler = new Qrcode();  qrcodeHandler.setQrcodeErrorCorrect('M');  qrcodeHandler.setQrcodeEncodeMode('B');  qrcodeHandler.setQrcodeVersion(7);   System.out.println(content);  byte[] contentBytes = content.getBytes("gb2312");   BufferedImage bufImg = new BufferedImage(140, 140,   BufferedImage.TYPE_INT_RGB);   Graphics2D gs = bufImg.createGraphics();   gs.setBackground(Color.WHITE);  gs.clearRect(0, 0, 140, 140);   // 设定图像颜色> BLACK  gs.setColor(Color.BLACK);   // 设置偏移量 不设置可能导致解析出错  int pixoff = 2;  // 输出内容> 二维码  if (contentBytes.length > 0 && contentBytes.length < 120) {  boolean[][] codeOut = qrcodeHandler.calQrcode(contentBytes);  for (int i = 0; i < codeOut.length; i++) {   for (int j = 0; j < codeOut.length; j++) {   if (codeOut[j][i]) {   gs.fillRect(j * 3 + pixoff, i * 3 + pixoff, 3, 3);   }   }  }  } else {  System.err.println("QRCode content bytes length = "   + contentBytes.length + " not in [ 0,120 ]. ");  }   gs.dispose();  bufImg.flush();   File imgFile = new File(imgPath);   // 生成二维码QRCode图片  ImageIO.write(bufImg, "png", imgFile);   } catch (Exception e) {  e.printStackTrace();  }   }   /** * @param args the command line arguments */  public static void main(String[] args) {  String imgPath = "D:/test/twocode/Michael_QRCode.png";   String content = "Hello 大大、小小,welcome to QRCode!"  + "/nMyblog [ http://sjsky.iteye.com ]"  + "/nEMail [ sjsky007@gmail.com ]" + "/nTwitter [ @suncto ]";   QRCodeEncoderHandler handler = new QRCodeEncoderHandler();  handler.encoderQRCode(content, imgPath);   System.out.println("encoder QRcode success");  } }

package michael.qrcode;  import java.awt.image.BufferedImage; import java.io.File; import java.io.IOException;  import javax.imageio.ImageIO;  import jp.sourceforge.qrcode.QRCodeDecoder; import jp.sourceforge.qrcode.data.QRCodeImage; import jp.sourceforge.qrcode.exception.DecodingFailedException;  /** * @blog http://sjsky.iteye.com * @author Michael */ public class QRCodeDecoderHandler {   /** * 解码二维码 * @param imgPath * @return String */  public String decoderQRCode(String imgPath) {   // QRCode 二维码图片的文件  File imageFile = new File(imgPath);   BufferedImage bufImg = null;  String decodedData = null;  try {  bufImg = ImageIO.read(imageFile);   QRCodeDecoder decoder = new QRCodeDecoder();  decodedData = new String(decoder.decode(new J2SEImage(bufImg)));   // try {  // System.out.println(new String(decodedData.getBytes("gb2312"),  // "gb2312"));  // } catch (Exception e) {  // // TODO: handle exception  // }  } catch (IOException e) {  System.out.println("Error: " + e.getMessage());  e.printStackTrace();  } catch (DecodingFailedException dfe) {  System.out.println("Error: " + dfe.getMessage());  dfe.printStackTrace();  }  return decodedData;  }   /** * @param args the command line arguments */  public static void main(String[] args) {  QRCodeDecoderHandler handler = new QRCodeDecoderHandler();  String imgPath = "d:/test/twocode/Michael_QRCode.png";  String decoderContent = handler.decoderQRCode(imgPath);  System.out.println("解析结果如下：");  System.out.println(decoderContent);  System.out.println("========decoder success!!!");  }   class J2SEImage implements QRCodeImage {  BufferedImage bufImg;   public J2SEImage(BufferedImage bufImg) {  this.bufImg = bufImg;  }   public int getWidth() {  return bufImg.getWidth();  }   public int getHeight() {  return bufImg.getHeight();  }   public int getPixel(int x, int y) {  return bufImg.getRGB(x, y);  }   } }