java二维码生成 zxing

￡神魔★判官ぃ 2021-09-10 07:42 569阅读 0赞

二维码分类  
线性堆叠二维码  
邮政码  
矩阵式二维码（常用） 通过矩形空间黑白像素不同分布进行编码。点出现是1，不出现0.比如QR Code

二维码的优点：高密度编码，信息容量大；编码范围广；容错能力强；译码可靠性高；可引入加密措施；成本低，易制作，持久耐用。  
缺点：手机病毒、钓鱼网站传播渠道

注意：添加http://头才会识别为链接而不是文本

使用google的zxing  
[官方github][github]  
maven配置

<dependency>
                <groupId>com.google.zxing</groupId>
                <artifactId>javase</artifactId>
                <version>3.3.0</version>
            </dependency>

import com.google.zxing.BarcodeFormat;
    import com.google.zxing.EncodeHintType;
    import com.google.zxing.MultiFormatWriter;
    import com.google.zxing.WriterException;
    import com.google.zxing.client.j2se.MatrixToImageWriter;
    import com.google.zxing.common.BitMatrix;
    import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
    
    
    
    import java.awt.image.BufferedImage;
    import java.io.*;
    import java.util.HashMap;
    import java.util.Map;
    
    /**
     * @author icecrea on 18-1-5
     */
    public class QRCodeUtil {
        private static final int width = 300;// 默认二维码宽度
        private static final int height = 300;// 默认二维码高度
        private static final String format = "png";// 默认二维码文件格式
        private static final Map<EncodeHintType, Object> hints = new HashMap();// 二维码参数
    
        static {
            hints.put(EncodeHintType.CHARACTER_SET, "utf-8");// 字符编码
            hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);// 容错等级 L、M、Q、H 其中 L 为最低, H 为最高
            hints.put(EncodeHintType.MARGIN, 2);// 二维码与图片边距
        }
        /**
         * 返回一个 BufferedImage 对象
         * @param content 二维码内容
         * @param width   宽
         * @param height  高
         */
        public static BufferedImage toBufferedImage(String content, int width, int height) throws WriterException, IOException {
            BitMatrix bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, width, height, hints);
            return MatrixToImageWriter.toBufferedImage(bitMatrix);
        }
        /**
         * 将二维码图片输出到一个流中
         * @param content 二维码内容
         * @param stream  输出流
         * @param width   宽
         * @param height  高
         */
        public static void writeToStream(String content, OutputStream stream, int width, int height) throws WriterException, IOException {
            BitMatrix bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, width, height, hints);
            MatrixToImageWriter.writeToStream(bitMatrix, format, stream);
        }
        /**
         * 生成二维码图片文件
         * @param content 二维码内容
         * @param path    文件保存路径
         * @param width   宽
         * @param height  高
         */
        public static void createQRCode(String content, String path, int width, int height) throws WriterException, IOException {
            BitMatrix bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, width, height, hints);
            //toPath() 方法由 jdk1.7 及以上提供
            MatrixToImageWriter.writeToPath(bitMatrix, format, new File(path).toPath());
        }
    
        public static void main(String[] args) throws Exception {
            OutputStream outputStream=new FileOutputStream(new File("/home/icecrea/hello.png"));
            QRCodeUtil.writeToStream("www.baidu.com",outputStream,width,height);
            QRCodeUtil.createQRCode("www.qunar.com","/home/icecrea/qunar.png",width,height);
        }
    }

在spring mvc中，可以通过流的形式在显示图片，抽象出如下工具类

public class QRCodeUtil {
        private static Logger logger = LoggerFactory.getLogger(QRCodeUtil.class);
        // 默认二维码宽度
        private static final int width = 300;
        // 默认二维码高度
        private static final int height = 300;
        // 默认二维码文件格式
        private static final String format = "png";
        // 二维码参数
        private static final Map<EncodeHintType, Object> hints = new HashMap();
     
        static {
            // 字符编码
            hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
            // 容错等级 L、M、Q、H 其中 L 为最低, H 为最高
            hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
            // 二维码与图片边距
            hints.put(EncodeHintType.MARGIN, 2);
        }
     
        public static void generateQRCode(String url, HttpServletResponse response) throws Exception {
            Preconditions.checkArgument(!Strings.isNullOrEmpty(url), "连接地址为空");
            generateQRCode(url,response,height,width);
        }
     
        public static void generateQRCode(String url, HttpServletResponse response, int height, int width) throws Exception {
            Preconditions.checkArgument(!Strings.isNullOrEmpty(url), "连接地址为空");
            OutputStream stream = null;
            try {
                stream = response.getOutputStream();
                BitMatrix bitMatrix = new MultiFormatWriter().encode(url, BarcodeFormat.QR_CODE, height, width, hints);
                MatrixToImageWriter.writeToStream(bitMatrix, format, stream);
            } finally {
                if (stream != null) {
                    stream.close();
                }
            }
        }
    }

@RequestMapping("qrcode")
    public void qrcode(HttpServletRequest httpServletRequest,HttpServletResponse httpServletResponse){
        try {
            QRCodeUtil.generateQRCode("http://www.qunar.com",httpServletResponse);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

生成Logo版本

package com.sdu.util;
    
    import com.google.common.base.Preconditions;
    import com.google.common.base.Strings;
    import com.google.zxing.BarcodeFormat;
    import com.google.zxing.EncodeHintType;
    import com.google.zxing.MultiFormatWriter;
    import com.google.zxing.common.BitMatrix;
    import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
    
    import javax.imageio.ImageIO;
    import javax.servlet.http.HttpServletResponse;
    import java.awt.*;
    import java.awt.geom.RoundRectangle2D;
    import java.awt.image.BufferedImage;
    import java.io.IOException;
    import java.io.OutputStream;
    import java.net.URL;
    import java.util.HashMap;
    import java.util.Map;
    
    import static com.google.zxing.client.j2se.MatrixToImageConfig.BLACK;
    import static com.google.zxing.client.j2se.MatrixToImageConfig.WHITE;
    
    /**
     * @author ligen
     * @create 2018-01-09 下午9:02
     */
    public class QRCodeUtil {
        /**
         * 默认二维码宽度
         */
        private static final int width = 300;
        /**
         * 默认二维码高度
         */
        private static final int height = 300;
        /**
         * 默认二维码文件格式
         */
        private static final String format = "png";
        /**
         * 二维码参数
         */
        private static final Map<EncodeHintType, Object> hints = new HashMap();
    
        static {
            // 字符编码
            hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
            // 容错等级 L、M、Q、H 其中 L 为最低, H 为最高
            hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
            // 二维码与图片边距
            hints.put(EncodeHintType.MARGIN, 1);
        }
    
        public static void generateQRCode(String url, HttpServletResponse response) throws Exception {
            Preconditions.checkArgument(!Strings.isNullOrEmpty(url), "连接地址为空");
            generateQRCode(url,response,height,width);
        }
    
        public static void generateQRCode(String url, HttpServletResponse response, int height, int width) {
            Preconditions.checkArgument(!Strings.isNullOrEmpty(url), "连接地址为空");
    
            try (OutputStream stream= response.getOutputStream()){
                BitMatrix bitMatrix = new MultiFormatWriter().encode(url, BarcodeFormat.QR_CODE, height, width, hints);
    //            MatrixToImageWriter.writeToStream(bitMatrix, format, stream);
                BufferedImage bufferedImage=toBufferedImage(bitMatrix);
                bufferedImage=setMatrixLogo(bufferedImage,"http://i.ce.cn/ce/aero/201601/04/W020160104629730930933.jpg");
                ImageIO.write(bufferedImage,format,stream);
            } catch (Exception e){
    //            log.error("生成二维码失败",e);
            }
        }
    
        public static BufferedImage setMatrixLogo(BufferedImage matrixImage,String logUri) throws IOException{
            /**
             * 读取二维码图片，并构建绘图对象
             */
            Graphics2D g2 = matrixImage.createGraphics();
            int matrixWidth = matrixImage.getWidth();
            int matrixHeigh = matrixImage.getHeight();
    
            /**
             * 读取Logo图片
             */
            BufferedImage logo = ImageIO.read(new URL(logUri));
    
            //开始绘制图片
            g2.drawImage(logo,matrixWidth/5*2,matrixHeigh/5*2, matrixWidth/5, matrixHeigh/5, null);
            //绘制边框
            BasicStroke stroke = new BasicStroke(5,BasicStroke.CAP_ROUND,BasicStroke.JOIN_ROUND);
            // 设置笔画对象
            g2.setStroke(stroke);
            //指定弧度的圆角矩形
            RoundRectangle2D.Float round = new RoundRectangle2D.Float(matrixWidth/5*2, matrixHeigh/5*2, matrixWidth/5, matrixHeigh/5,20,20);
            g2.setColor(Color.white);
            // 绘制圆弧矩形
            g2.draw(round);
    
            //设置logo 有一道灰色边框
            BasicStroke stroke2 = new BasicStroke(1,BasicStroke.CAP_ROUND,BasicStroke.JOIN_ROUND);
            // 设置笔画对象
            g2.setStroke(stroke2);
            RoundRectangle2D.Float round2 = new RoundRectangle2D.Float(matrixWidth/5*2+2, matrixHeigh/5*2+2, matrixWidth/5-4, matrixHeigh/5-4,20,20);
            g2.setColor(new Color(128,128,128));
            g2.draw(round2);// 绘制圆弧矩形
    
    
            g2.dispose();
            matrixImage.flush() ;
            return matrixImage ;
        }
    
        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));
    //              image.setRGB(x, y,  (matrix.get(x, y) ? Color.YELLOW.getRGB() : Color.CYAN.getRGB()));
                }
            }
            return image;
        }
    
    }

参考文章：  
[https://www.jianshu.com/p/05e9ee773898][https_www.jianshu.com_p_05e9ee773898]  
[https://www.jianshu.com/p/7ae3b7002530][https_www.jianshu.com_p_7ae3b7002530]

[github]: https://link.jianshu.com?t=https%3A%2F%2Fgithub.com%2Fzxing%2Fzxing%2Fblob%2Fmaster%2FREADME.md
[https_www.jianshu.com_p_05e9ee773898]: https://www.jianshu.com/p/05e9ee773898
[https_www.jianshu.com_p_7ae3b7002530]: https://www.jianshu.com/p/7ae3b7002530