涉及到的一些主要类库，方便大家下载：

• 二维码编码lib:Qrcode_swetake.jar（官网介绍 -- http://www.swetake.com/qr/index-e.html）
  
• 二维码解码lib:qrcode.jar （官网介绍 -- http://sourceforge.jp/projects/qrcode/）

java二维码 生成二维码 QRCodeEncoderHandler.java

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://zhblog.github.com/blog   * @author zzh   */  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("utf-8");                BufferedImage bufImg = new BufferedImage(140, 140,                      BufferedImage.TYPE_INT_RGB);                Graphics2D gs = bufImg.createGraphics();                gs.setBackground(Color.cyan);              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 = "./zzh.png";            String content = "\t江湖在喝酒的路上"                  + "\nMyblog  :http://zhblog.github.com/blog"                  + "\nEMail   :jack.zh.1986@gmail.com"                  + "\nQQ      :715443050";            QRCodeEncoderHandler handler = new QRCodeEncoderHandler();          handler.encoderQRCode(content, imgPath);          System.out.println("encoder QRcode success");      }  }

java二维码解码 QRCodeDecoderHandler.java

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://zhblog.github.com/blog   * @author zzh   */  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)));          } 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 = "zzh.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);          }        }  }