生成二维码与转换二维码为base64字符串

 所需jar包

    <!-- 生成二维码 --> 
    <dependency>
        <groupId>com.google.zxing</groupId>
        <artifactId>core</artifactId>
        <version>3.3.3</version>
    </dependency>
    <dependency>
        <groupId>com.google.zxing</groupId>
        <artifactId>javase</artifactId>
        <version>3.3.3</version>
    </dependency>

工具类

import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import javax.imageio.ImageIO;

import java.util.Hashtable;

import com.google.zxing.common.BitMatrix;
import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

 /**
  * 生成二维码与转换二维码为base64字符串
  */
public class MatrixToImageWriter {
     private static final int BLACK = 0xFF000000;
     private static final int WHITE = 0xFFFFFFFF;

     private MatrixToImageWriter() {
     }

     
     /**
      * 生成二维码
      *
      * @param content
      * @return
      * @throws Exception
      */
     public static InputStream createQrcodeImage(String content) throws Exception {
    	 int width = 200; // 二维码图片宽度
         int height = 200; // 二维码图片高度
         String format = "jpg";// 二维码的图片格式
         Hashtable<EncodeHintType, String> hints = new Hashtable<EncodeHintType, String>();
         hints.put(EncodeHintType.CHARACTER_SET, "utf-8"); // 内容所使用字符集编码
         BitMatrix bitMatrix = new MultiFormatWriter().encode(content,
                 BarcodeFormat.QR_CODE, width, height, hints);
         BufferedImage image= MatrixToImageWriter.toBufferedImage(bitMatrix);
         InputStream is=MatrixToImageWriter.toInputStream(image);
         return is;

     }
     
     /**
      * @Description: 根据图片地址转换为base64编码字符串
      * @Author: 
      * @CreateTime: 
      * @return
      */
     public static String getImageStr(InputStream inputStream) {
         byte[] data = null;
         try {
             data = new byte[inputStream.available()];
             inputStream.read(data);
             inputStream.close();
         } catch (IOException e) {
             e.printStackTrace();
         }
         // 加密
         BASE64Encoder encoder = new BASE64Encoder();
         return encoder.encode(data);
     }
     
     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 InputStream toInputStream(BufferedImage image) throws Exception {
         ByteArrayOutputStream os = new ByteArrayOutputStream();
         ImageIO.write(image, "jpg", os);
         InputStream is = new ByteArrayInputStream(os.toByteArray());
         return is;
     }

     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);
         }
     }
     
     

     public static void main(String[] args) throws Exception {
    	 try{
	    	 String text = "http://www.baidu.com"; // 二维码内容
	         int width = 200; // 二维码图片宽度
	         int height = 200; // 二维码图片高度
	         String format = "jpg";// 二维码的图片格式
	
	         Hashtable<EncodeHintType, String> hints = new Hashtable<EncodeHintType, String>();
	         hints.put(EncodeHintType.CHARACTER_SET, "utf-8"); // 内容所使用字符集编码
	
	         BitMatrix bitMatrix = new MultiFormatWriter().encode(text,
	                 BarcodeFormat.QR_CODE, width, height, hints);
	         BufferedImage image= MatrixToImageWriter.toBufferedImage(bitMatrix);
	         InputStream is=MatrixToImageWriter.toInputStream(image);
	         // 生成二维码保存电脑路径
	         //File outputFile = new File("F:/d/new.jpg");
	         //MatrixToImageWriter.writeToFile(bitMatrix, format, outputFile);
         } catch (Exception e) {
        	 System.out.println("异常=="+e.getMessage());
 			e.printStackTrace();
 		}
     }



 }

使用例子