java基于谷歌开发的zxing包开发的二维码生成工具

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Hashtable;

import javax.imageio.ImageIO;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;
public class MatrixToImageWriter {
    
   private static final int BLACK = 0xFF000000; 
   private static final int WHITE = 0xFFFFFFFF; 
   private static final int WIDTH = 300;
   private static final int HEIGHT = 300;
    
   private MatrixToImageWriter() {} 
    
      
   public static BufferedImage toBufferedImage(BitMatrix matrix) { 
     int width = matrix.getWidth(); 
     int height = matrix.getHeight(); 
     BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); 
     for (int x = 0; x < width; x++) { 
       for (int y = 0; y < height; y++) { 
         image.setRGB(x, y, matrix.get(x, y) ? BLACK : WHITE); 
       } 
     } 
     return image; 
   } 
        
          
   public static void writeToFile(BitMatrix matrix, String format, File file)throws IOException { 
         BufferedImage image = toBufferedImage(matrix); 
         if (!ImageIO.write(image, format, file)) { 
           throw new IOException("Could not write an image of format " + format + " to " + file); 
         } 
    } 
        
          
   public static void writeToStream(BitMatrix matrix, String format, OutputStream stream) throws IOException { 
     BufferedImage image = toBufferedImage(matrix); 
     if (!ImageIO.write(image, format, stream)) { 
       throw new IOException("Could not write an image of format " + format); 
     } 
   } 
   
   //生成二维码图片content：内容 ，url：生成路径
   public static String genQRCode(String content,String url){
       
     //验证是否存在文件夹
        CreateDir.createDir(url);
       
       String filename = null;
     //二维码的图片格式 
       String format = "png"; 
       Hashtable hints = new Hashtable(); 
       //内容所使用编码 
       hints.put(EncodeHintType.CHARACTER_SET, "utf-8"); 
       BitMatrix bitMatrix;
        try {
            bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, WIDTH, HEIGHT, hints);
            
            //生成名字，如果有自己的特有规则，以下3行自行更改
            int s=(int)(Math.random()*10000);//整数类型
            SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");    
            filename = "file_" + sdf.format(new Date())+s +"." + format ;
            
            //生成二维码 
            File outputFile = new File(url+File.separator+filename); 
            MatrixToImageWriter.writeToFile(bitMatrix, format, outputFile); 
        } catch (WriterException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } 
       return filename;
   }
   
}