利用Zxing生成和识别二维码(java版本)

深碍√TFBOYSˉ_ 2023-06-17 06:57 5阅读 0赞

Zxing是Google开发的用来生成和识别二维码的库,可以帮助我们快速方便的生成和识别出二维码.

### 1.使用Zxing我们首先应该导入它的依赖 ###

<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>

### 2.二维码的生成与识别(带logo二维码和不带logo二维码) ###

`QrUtil.java`

package com.selenium.qr.web.util;
    
    import com.google.zxing.*;
    import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
    import com.google.zxing.client.j2se.MatrixToImageConfig;
    import com.google.zxing.client.j2se.MatrixToImageWriter;
    import com.google.zxing.common.BitMatrix;
    import com.google.zxing.common.CharacterSetECI;
    import com.google.zxing.common.HybridBinarizer;
    import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
    
    import javax.imageio.ImageIO;
    import java.awt.*;
    import java.awt.image.BufferedImage;
    import java.io.File;
    import java.io.IOException;
    import java.util.HashMap;
    import java.util.Map;
    
    public class QrUtil { 
        /** * 生成二维码 * * @param content 二维码内容 * @param width 二维码宽度 * @param height 二维码高度 * @throws Exception */
        public static void createQr(String content, int width, int height) throws Exception { 
            //二维码参数基本设置
            Map<EncodeHintType, Object> hints = new HashMap<>();
            //设置编码为UTF-8
            hints.put(EncodeHintType.CHARACTER_SET, CharacterSetECI.UTF8);
            //设置二维码纠错等级
            // L:7%纠错率 M:15%纠错率 Q:25%纠错率 H:30纠错率 纠错率越高越容易识别出来,但是纠错率越高识别速度越慢
            hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
            //设置二维码白边的范围(此值可能不生效)
            hints.put(EncodeHintType.MARGIN, 1);
            //设置生成的图片类型为QRCode
            BarcodeFormat format = BarcodeFormat.QR_CODE;
            //生成二维码对应的位矩阵对象
            BitMatrix matrix = new MultiFormatWriter().encode(content, format, width, height);
            //设置位矩阵对象转图片的参数(前景色,背景色)
            MatrixToImageConfig config = new MatrixToImageConfig(Color.black.getRGB(), Color.white.getRGB());
            //位矩阵对象转BufferedImage对象
            BufferedImage qrcode = MatrixToImageWriter.toBufferedImage(matrix, config);
            //将BufferedImage对象保存到本地
            ImageIO.write(qrcode, "png", new File("C:\\src\\idea\\qr-java\\qr.png"));
        }
    
        /** * 生成带logo的二维码 * * @param content 二维码内容 * @param width 二维码宽度 * @param height 二维码高度 * @param scale logo所占二维码比例,如果scale设置太小,即logo占二维码比例太大会识别不出二维码 * @throws Exception */
        public static void createQrWithLogo(String content, int width, int height, int scale) throws Exception { 
            //二维码参数基本设置
            Map<EncodeHintType, Object> hints = new HashMap<>();
            //设置编码为UTF-8
            hints.put(EncodeHintType.CHARACTER_SET, CharacterSetECI.UTF8);
            //设置二维码纠错等级
            // L:7%纠错率 M:15%纠错率 Q:25%纠错率 H:30纠错率 纠错率越高越容易识别出来,但是纠错率越高识别速度越慢
            hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
            //设置二维码白边的范围(此值可能不生效)
            hints.put(EncodeHintType.MARGIN, 1);
            //设置生成的图片类型为QRCode
            BarcodeFormat format = BarcodeFormat.QR_CODE;
            //生成二维码对应的位矩阵对象
            BitMatrix matrix = new MultiFormatWriter().encode(content, format, width, height);
            //设置位矩阵对象转图片的参数(前景色,背景色)
            MatrixToImageConfig config = new MatrixToImageConfig(Color.black.getRGB(), Color.white.getRGB());
            //位矩阵对象转BufferedImage对象
            BufferedImage qrcode = MatrixToImageWriter.toBufferedImage(matrix, config);
            //读取logo图片
            BufferedImage logo = ImageIO.read(new File("C:\\src\\idea\\qr-java\\logo.jpg"));
            //设置logo宽和高
            int logoWidth = qrcode.getWidth() / scale;
            int logoHeight = qrcode.getHeight() / scale;
            //设置返回logo的二维码图片的起始位置
            int x = (qrcode.getWidth() - logoWidth) / 2;
            int y = (qrcode.getHeight() - logoHeight) / 2;
            //新建空画板
            BufferedImage canvas = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
            //新建画笔
            Graphics2D g = (Graphics2D) canvas.getGraphics();
            //将二维码绘制到画板
            g.drawImage(qrcode, 0, 0, null);
            //设置不透明度
            g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER));
            //将logo绘制到画板上
            g.drawImage(logo, x, y, logoWidth, logoHeight, null);
            //将画板(BufferedImage)对象保存到本地
            ImageIO.write(canvas, "png", new File("C:\\src\\idea\\qr-java\\qrwithlogo.png"));
        }
    
        /** * 识别二维码 * * @param file * @return * @throws IOException * @throws NotFoundException */
        public static String recogQr(File file) throws IOException, NotFoundException { 
            MultiFormatReader reader = new MultiFormatReader();
            //将图片文件转为BufferedImage对象
            BufferedImage bufferedImage = ImageIO.read(file);
            //生成BinaryBitmap对象
            BinaryBitmap binaryBitmap = new BinaryBitmap(new HybridBinarizer(new BufferedImageLuminanceSource(bufferedImage)));
            //二维码参数基本设置
            Map<DecodeHintType, Object> hints = new HashMap<>();
            hints.put(DecodeHintType.CHARACTER_SET, CharacterSetECI.UTF8);
            //识别二维码
            Result result = reader.decode(binaryBitmap, hints);
            bufferedImage.flush();
            return result.getText();
        }
    }

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQ1NDUzMjY2_size_16_color_FFFFFF_t_70]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQ1NDUzMjY2_size_16_color_FFFFFF_t_70 1]

### 3.单元测试类 ###

`QrApplicationTests.java`

package com.selenium.qr.web;
    
    import com.google.zxing.NotFoundException;
    import com.selenium.qr.web.util.QrUtil;
    import org.junit.jupiter.api.Test;
    
    import java.io.File;
    import java.io.IOException;
    
    
    class QrApplicationTests { 
    
        /** * 测试创建二维码 */
        @Test
        public void testCreateQr() { 
            try { 
                QrUtil.createQr("https://blog.csdn.net/qq_45453266/article/details/103285051", 500, 500);
            } catch (Exception e) { 
                e.printStackTrace();
            }
        }
        /** * 测试创建带logo的二维码 */
        @Test
        public void testCreateQrWithLogo() { 
            try { 
                QrUtil.createQrWithLogo("https://blog.csdn.net/qq_45453266/article/details/103285051", 500, 500,10);
            } catch (Exception e) { 
                e.printStackTrace();
            }
        }
    
        /** * 测试识别二维码 */
        @Test
        public void testRecogQr() throws IOException, NotFoundException { 
            System.out.println(QrUtil.recogQr(new File("C:\\src\\idea\\qr-java\\qr.png")));
            System.out.println(QrUtil.recogQr(new File("C:\\src\\idea\\qr-java\\qrwithlogo.png")));
        }
    
    }

![在这里插入图片描述][20191128000111835.png]  
注意:如果识别的二维码是中文，但是显示确实???,可将内容转码  
`new String("我是中文".getBytes("UTF-8"), "ISO-8859-1")`

#### 4.补充 ####

1.  Zxing文档:[https://zxing.github.io/zxing/apidocs/][https_zxing.github.io_zxing_apidocs]
2.  Zxing在线识别二维码:[https://zxing.org/w/decode.jspx][https_zxing.org_w_decode.jspx](这里识别不出来,程序肯定也识别不出来)
3.  完整代码:[https://github.com/wantao666/qr-java][https_github.com_wantao666_qr-java]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQ1NDUzMjY2_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/20191127235901463.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQ1NDUzMjY2,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQ1NDUzMjY2_size_16_color_FFFFFF_t_70 1]: https://img-blog.csdnimg.cn/20191127235912982.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzQ1NDUzMjY2,size_16,color_FFFFFF,t_70
[20191128000111835.png]: https://img-blog.csdnimg.cn/20191128000111835.png
[https_zxing.github.io_zxing_apidocs]: https://zxing.github.io/zxing/apidocs/
[https_zxing.org_w_decode.jspx]: https://zxing.org/w/decode.jspx
[https_github.com_wantao666_qr-java]: https://github.com/wantao666/qr-java