一、准备工作

下载QR二维码包。

首先得下载zxing.jar 包, 我这里用的是3.3版本的core包

下载地址:现在已经迁移到了github:https://github.com/zxing/zxing/wiki/Getting-Started-Developing,

当然你也可以从maven仓库下载jar包:http://central.maven.org/maven2/com/google/zxing/core/

二、代码

part1:

import com.google.zxing.LuminanceSource;
	 
import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;
 import java.awt.image.BufferedImage;
	 
 /**
  * 
  * @author yuki_ho
  * 辅助类
  */
 public final class BufferedImageLuminanceSource extends LuminanceSource {
	 
	   private final BufferedImage image;
	   private final int left;
	   private final int top;
	 
	   public BufferedImageLuminanceSource(BufferedImage image) {
	     this(image, 0, 0, image.getWidth(), image.getHeight());
	   }
	 
	   public BufferedImageLuminanceSource(BufferedImage image, int left, int top, int width, int height) {
	     super(width, height);
	 
	     int sourceWidth = image.getWidth();
	     int sourceHeight = image.getHeight();
	     if (left + width > sourceWidth || top + height > sourceHeight) {
	       throw new IllegalArgumentException("Crop rectangle does not fit within image data.");
	     }
	 
	     for (int y = top; y < top + height; y++) {
	       for (int x = left; x < left + width; x++) {
	         if ((image.getRGB(x, y) & 0xFF000000) == 0) {
	           image.setRGB(x, y, 0xFFFFFFFF); // = white
	         }
	       }
	     }
	 
	     this.image = new BufferedImage(sourceWidth, sourceHeight, BufferedImage.TYPE_BYTE_GRAY);
	     this.image.getGraphics().drawImage(image, 0, 0, null);
	     this.left = left;
	     this.top = top;
	   }
	 
	// 这里要得到指定行的像素数据  
	   @Override
	   public byte[] getRow(int y, byte[] row) {
	     if (y < 0 || y >= getHeight()) {
	       throw new IllegalArgumentException("Requested row is outside the image: " + y);
	     }
	     int width = getWidth();
	     if (row == null || row.length < width) {
	       row = new byte[width];
	     }
	     image.getRaster().getDataElements(left, top + y, width, 1, row);
	     return row;
	   }
	 
	   // 返回我们生成好的像素数据 
	   @Override
	   public byte[] getMatrix() {
	     int width = getWidth();
	     int height = getHeight();
	     int area = width * height;
	     byte[] matrix = new byte[area];
	     image.getRaster().getDataElements(left, top, width, height, matrix);
	     return matrix;
	   }
	 
	   @Override
	   public boolean isCropSupported() {
	     return true;
	   }
	 
	   @Override
	   public LuminanceSource crop(int left, int top, int width, int height) {
	     return new BufferedImageLuminanceSource(image, this.left + left, this.top + top, width, height);
	   }
	 
	   @Override
	   public boolean isRotateSupported() {
	     return true;
	   }
	 
	   @Override
	   public LuminanceSource rotateCounterClockwise() {
	 
	      int sourceWidth = image.getWidth();
	     int sourceHeight = image.getHeight();
	 
	     AffineTransform transform = new AffineTransform(0.0, -1.0, 1.0, 0.0, 0.0, sourceWidth);
	 
	     BufferedImage rotatedImage = new BufferedImage(sourceHeight, sourceWidth, BufferedImage.TYPE_BYTE_GRAY);
	 
	     Graphics2D g = rotatedImage.createGraphics();
	     g.drawImage(image, transform, null);
	     g.dispose();
	 
	     int width = getWidth();
	     return new BufferedImageLuminanceSource(rotatedImage, top, sourceWidth - (left + width), getHeight(), width);
	   }
}

part2:

import java.awt.BasicStroke;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Shape;
import java.awt.geom.RoundRectangle2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Hashtable;
import java.util.UUID;

import javax.imageio.ImageIO;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.DecodeHintType;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatReader;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.Result;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;

/** 
 * 二维码 生成、解析器 帮助类 
 * @author yuki_ho 
 * 
 */  
public class QRCodeUtil {  
     private static final String CHARSET = "utf-8";  
        private static final String FORMAT_NAME = "JPG";  
        // 二维码尺寸  
        private static final int QRCODE_SIZE = 300;  
        // LOGO宽度  
        private static final int WIDTH = 60;  
        // LOGO高度  
        private static final int HEIGHT = 60;  
  
        
        /** 
         *  检查路径 图片是否存在 
         * @param imgPath 
         * @return 
         * @throws IOException 
         */  
        private static BufferedImage CheckImageExist(String imgPath) throws IOException{  
            File file = new File(imgPath);  
            if (!file.exists()) {  
                System.err.println(""+imgPath+"   该文件不存在！");  
                return null;  
            }  
            BufferedImage src = ImageIO.read(new File(imgPath));  
            return src;  
        }  
          
        
        /** 
         * 创建 二维码所需图片  
         * @param content   内容 
         * @param imgPath   Logo图片地址 
         * @param needCompress 是否压缩Logo大小
         * @param needDescription 是否需要底部描述 
         * @return   
         * @throws Exception 
         */  
        private static BufferedImage createImage(String content,BufferedImage logoImage, String bottomDes,
                boolean needCompress) throws Exception {  
            Hashtable hints = new Hashtable();  
            hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H); //容错级别 H->30%  
            hints.put(EncodeHintType.CHARACTER_SET, CHARSET);  
            hints.put(EncodeHintType.MARGIN, 1);  
            BitMatrix bitMatrix = new MultiFormatWriter().encode(content,  
                    BarcodeFormat.QR_CODE, QRCODE_SIZE, QRCODE_SIZE, hints);  
            int width = bitMatrix.getWidth();  
            int height = bitMatrix.getHeight(); 
            int tempHeight = height;
            boolean needDescription=(null==bottomDes&&"".equals(bottomDes));
            if (needDescription) {
                tempHeight += 30;
            } 
            BufferedImage image = new BufferedImage(width, tempHeight,  
                    BufferedImage.TYPE_INT_RGB); 
            for (int x = 0; x < width; x++) {  
                for (int y = 0; y < height; y++) {  
                    image.setRGB(x, y, bitMatrix.get(x, y) ? 0xFF000000  
                            : 0xFFFFFFFF);  
                }  
            }  
            
            if(null==logoImage)  
                 return image;  
              
            // 插入图片  
            QRCodeUtil.insertImage(image, logoImage, needCompress);
            
            if(needDescription)
                 return image;
            
            QRCodeUtil.addFontImage(image, bottomDes);
            
            return image;  
        }  
      
        /**
         * 添加 底部图片文字
         * @param source   图片源
         * @param declareText 文字本文
         */
        private static void addFontImage(BufferedImage source, String declareText) {
            BufferedImage textImage = FontImage.getImage(declareText, QRCODE_SIZE, 50);
            Graphics2D graph = source.createGraphics();
            
            int width = textImage.getWidth(null);  
            int height = textImage.getHeight(null);  
              
            Image src =textImage;  
            graph.drawImage(src, 0, QRCODE_SIZE - 20, width, height, null);   
            graph.dispose();  
        }

        /** 
         *  插入Logo图片 
         * @param source    图片操作对象 
         * @param imgPath   Logo图片地址 
         * @param needCompress 是否压缩Logo大小 
         * @throws Exception 
         */  
        private static void insertImage(BufferedImage source,BufferedImage logoImage,  
                boolean needCompress) throws Exception {  
            int width = logoImage.getWidth(null);  
            int height = logoImage.getHeight(null);  
              
            Image src =logoImage;  
            if (needCompress) { 
                if (width > WIDTH) {  
                    width = WIDTH;  
                }  
                if (height > HEIGHT) {  
                    height = HEIGHT;  
                }  
  
                Image  image = logoImage.getScaledInstance(width, height,  
                Image.SCALE_SMOOTH);  
                BufferedImage tag = new BufferedImage(width, height,  
                        BufferedImage.TYPE_INT_RGB);  
                Graphics g = tag.getGraphics();  
                g.drawImage(image, 0, 0, null); 
                g.dispose();  
                src = image;  
            }  
            Graphics2D graph = source.createGraphics();  
            int x = (QRCODE_SIZE - width) / 2;  
            int y = (QRCODE_SIZE - height) / 2;  
            graph.drawImage(src, x, y, width, height, null);   
            Shape shape = new RoundRectangle2D.Float(x, y, width, width, 6, 6);  
            graph.setStroke(new BasicStroke(3f));  
            graph.draw(shape);  
            graph.dispose();  
        }  
  
        /** 
         * 创建 目录 
         * @param destPath 
         */  
        public static void mkdirs(String destPath) {  
                File file =new File(destPath);     
                //当文件夹不存在时，mkdirs会自动创建多层目录，区别于mkdir．(mkdir如果父目录不存在则会抛出异常)  
                if (!file.exists() && !file.isDirectory()) {  
                    file.mkdirs();  
                }  
            }  
          
        
        /** 
         *  生成二维码 (以Logo路径) 
         * @param content  内容 (若带http:// 会自动跳转) 
         * @param imgPath  Logo 图片地址 
         * @param destPath   保存二维码 地址 (没有该目录会自动创建) 
         * @param bottomDes 底部文字描述
         * @param needCompress 是否压缩Logo大小 
         * @throws Exception 
         */  
        public static void encodeOfPath(String content, String imgPath,String bottomDes,String destPath,  
                boolean needCompress) throws Exception {  
              
            BufferedImage image = QRCodeUtil.createImage(content, CheckImageExist(imgPath),  
                    bottomDes,needCompress);  
            mkdirs(destPath);  
            String file = UUID.randomUUID().toString()+".jpg";  
            ImageIO.write(image, FORMAT_NAME, new File(destPath+"/"+file));  
        }  
          

        /**
         * 
         * @param content 内容    
         * @param logoImage  图片源 LOGO
         * @param bottomDes 底部描述文字
         * @param destPath   保存二维码 地址 (没有该目录会自动创建)
         * @param needCompress  是否压缩logo
         * @throws Exception
         */
        public static void encode(String content, BufferedImage logoImage,String bottomDes, String destPath,  
                boolean needCompress) throws Exception {  
              
            BufferedImage image = QRCodeUtil.createImage(content, logoImage, bottomDes, 
                    needCompress);  
            mkdirs(destPath);  
            String file = UUID.randomUUID().toString()+".jpg";  
            ImageIO.write(image, FORMAT_NAME, new File(destPath+"/"+file));  
        }  
        
        /**
         * 
         * @param content  内容    
         * @param logoImage  图片源LOGO
         * @param bottomDes 底部描述文字
         * @param picName   图片名
         * @param destPath     保存二维码 地址 (没有该目录会自动创建)
         * @param needCompress 是否压缩logo
         * @throws Exception
         */
        public static void encode(String content, BufferedImage logoImage,String bottomDes,String picName,String destPath,  
                boolean needCompress) throws Exception {          
            BufferedImage image=QRCodeUtil.createImage(content, logoImage,bottomDes, 
                        needCompress);  
    
            mkdirs(destPath);  
            String file = picName+".jpg";  
            ImageIO.write(image, FORMAT_NAME, new File(destPath+"/"+file));  
        } 
        

        /**
         * 
         * @param content  内容
         * @param destPath     保存二维码 地址 (没有该目录会自动创建)
         * @throws Exception
         */
        public static void encode(String content, String destPath) throws Exception {  
            QRCodeUtil.encode(content, null,null,destPath, false);  
        }  
  
        /**
         *   
         * @param content   内容
         * @param imgPath    图片源地址LOGO
         * @param bottomDes 底部描述文字
         * @param output    输出流
         * @param needCompress 是否压缩logo
         * @throws Exception
         */
        public static void encodeOfPath(String content, String imgPath,String bottomDes,  
                OutputStream output, boolean needCompress) throws Exception {  
            BufferedImage image = QRCodeUtil.createImage(content, CheckImageExist(imgPath), bottomDes, 
                    needCompress);  
            ImageIO.write(image, FORMAT_NAME, output);  
        }  
          
        /**
         * 
         * @param content  内容
         * @param Image        图片源LOGO
         * @param bottomDes 底部描述文字
         * @param output    输出流
         * @param needCompress 是否压缩
         * @throws Exception
         */
        public static void encode(String content, BufferedImage Image,String bottomDes,  
                OutputStream output, boolean needCompress) throws Exception {  
            BufferedImage image = QRCodeUtil.createImage(content, Image, bottomDes,  
                    needCompress);  
            ImageIO.write(image, FORMAT_NAME, output);  
        }  
          
        /**
         * 
         * @param content 内容
         * @param output    输出流
         * @throws Exception
         */
        public static void encode(String content, OutputStream output)  
                throws Exception {  
            QRCodeUtil.encode(content, null,null, output, false);  
        }  
  
        /** 
         * 解析 二维码 
         * @param file 图片文件 
         * @return 
         * @throws Exception 
         */  
        public static String decode(File file) throws Exception {  
            BufferedImage image;  
            image = ImageIO.read(file);  
            if (image == null) {  
                return null;  
            }  
            BufferedImageLuminanceSource source = new BufferedImageLuminanceSource(  
                    image);  
            BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));  
            Result result;  
            Hashtable hints = new Hashtable();  
            hints.put(DecodeHintType.CHARACTER_SET, CHARSET);  
            result = new MultiFormatReader().decode(bitmap, hints);  
            String resultStr = result.getText();  
            return resultStr;  
        }  
   
        /** 
         *  解析二维码 
         * @param path 图片地址 
         * @return 
         * @throws Exception 
         */ 
        public static String decode(String path) throws Exception {  
            return QRCodeUtil.decode(new File(path));  
        }  
             
        public static void main(String[] args) throws Exception {  
            String text = "http://www.baidu.com";  
//            QRCodeUtil.encodeOfPath(text, "d:/test/a1.jpg",null,"d:/test", true);  
//            QRCodeUtil.encode(text,"d:/test"); // 不带logo 
            BufferedImage bi = ImageIO.read(new File("d:/test/a1.jpg"));
               QRCodeUtil.encode(text,bi,"ok","123","d:/test", true);
        }  
          

	    
	    
}

三、调用测试

如果要 中间写文字可以参考:地址