【20200201】SpringBoot ZXing - 《乐谷技术学习笔记（可公开）》

首先，在pom文件中引入zxing的两个架包：
接着编写工具类，进行测试；
最后，测试结果如下：

二维码称为QR Code，QR全称Quick Response。下面直接上代码，看看在java语言里如何生成二维码的吧。

首先，在pom文件中引入zxing的两个架包：

<!--二维码生成架包引用-->
<!-- https://mvnrepository.com/artifact/com.google.zxing/core -->
<dependency>
    <groupId>com.google.zxing</groupId>
    <artifactId>core</artifactId>
    <version>3.3.3</version>
</dependency>
<!-- https://mvnrepository.com/artifact/com.google.zxing/javase -->
<dependency>
    <groupId>com.google.zxing</groupId>
    <artifactId>javase</artifactId>
    <version>3.3.3</version>
</dependency>

接着编写工具类，进行测试；

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.util.Hashtable;
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.client.j2se.BufferedImageLuminanceSource;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
/**
 * 二维码生成解析工具类
 * @author 程就人生
 * @date 2019年7月27日
 * @Description 
 *
 */
public class QRCodeUtil {
    //编码格式,采用utf-8
    private static final String UNICODE = "utf-8";
    //图片格式
    private static final String FORMAT = "JPG";
    //二维码宽度,单位：像素pixels
    private static final int QRCODE_WIDTH = 300;
    //二维码高度,单位：像素pixels
    private static final int QRCODE_HEIGHT = 300;
    //LOGO宽度,单位：像素pixels
    private static final int LOGO_WIDTH = 100;
    //LOGO高度,单位：像素pixels
    private static final int LOGO_HEIGHT = 100;
    /**
     * 生成二维码图片
     * @param content 二维码内容
     * @param logoPath 图片地址
     * @param needCompress 是否压缩
     * @return
     * @throws Exception
     */
    private static BufferedImage createImage(String content, String logoPath, boolean needCompress) throws Exception {
        Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
        hints.put(EncodeHintType.CHARACTER_SET, UNICODE);
        hints.put(EncodeHintType.MARGIN, 1);
        BitMatrix bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, QRCODE_WIDTH, QRCODE_HEIGHT,
                hints);
        int width = bitMatrix.getWidth();
        int height = bitMatrix.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, bitMatrix.get(x, y) ? 0xFF000000 : 0xFFFFFFFF);
            }
        }
        if (logoPath == null || "".equals(logoPath)) {
            return image;
        }
        // 插入图片
        QRCodeUtil.insertImage(image, logoPath, needCompress);
        return image;
    }
    /**
     * 插入LOGO
     * @param source 二维码图片
     * @param logoPath LOGO图片地址
     * @param needCompress 是否压缩
     * @throws Exception
     */
    private static void insertImage(BufferedImage source, String logoPath, boolean needCompress) throws Exception {
        File file = new File(logoPath);
        if (!file.exists()) {
            throw new Exception("logo file not found.");
        }
        Image src = ImageIO.read(new File(logoPath));
        int width = src.getWidth(null);
        int height = src.getHeight(null);
        if (needCompress) { // 压缩LOGO
            if (width > LOGO_WIDTH) {
                width = LOGO_WIDTH;
            }
            if (height > LOGO_HEIGHT) {
                height = LOGO_HEIGHT;
            }
            Image image = src.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); // 绘制缩小后的图
            g.dispose();
            src = image;
        }
        // 插入LOGO
        Graphics2D graph = source.createGraphics();
        int x = (QRCODE_WIDTH - width) / 2;
        int y = (QRCODE_HEIGHT - 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();
    }
    /**
     * 生成二维码(内嵌LOGO)
     * 调用者指定二维码文件名
     * @param content 二维码的内容
     * @param logoPath 中间图片地址
     * @param destPath 存储路径
     * @param fileName 文件名称
     * @param needCompress 是否压缩
     * @return
     * @throws Exception
     */
    public static String encode(String content, String logoPath, String destPath, String fileName, boolean needCompress) throws Exception {
        BufferedImage image = QRCodeUtil.createImage(content, logoPath, needCompress);
        mkdirs(destPath);
        //文件名称通过传递
        fileName = fileName.substring(0, fileName.indexOf(".")>0?fileName.indexOf("."):fileName.length())
                + "." + FORMAT.toLowerCase();
        ImageIO.write(image, FORMAT, new File(destPath + "/" + fileName));
        return fileName;
    }
    /**
     * 创建文件夹， 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)
     * @param destPath
     */
    public static void mkdirs(String destPath) {
        File file = new File(destPath);
        if (!file.exists() && !file.isDirectory()) {
            file.mkdirs();
        }
    }
    /**
     * 解析二维码
     * @param path 二维码图片路径
     * @return String 二维码内容
     * @throws Exception
     */
    public static String decode(String path) throws Exception {
        File file = new File(path);
        BufferedImage image = ImageIO.read(file);
        if (image == null) {
            return null;
        }
        BufferedImageLuminanceSource source = new BufferedImageLuminanceSource(image);
        BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
        Result result;
        Hashtable<DecodeHintType, Object> hints = new Hashtable<DecodeHintType, Object>();
        hints.put(DecodeHintType.CHARACTER_SET, UNICODE);
        result = new MultiFormatReader().decode(bitmap, hints);
        return result.getText();
    }
    /**
     * 测试
     * @param args
     * @throws Exception
     */
    public static void main(String[] args) throws Exception {
        String text = "http://localhost:8001/login/aaa?bbb=ccc";
        //不含Logo
        QRCodeUtil.encode(text, null, "D:\\cc\\", "qrcode", true);        
        //含Logo，指定二维码图片名
        QRCodeUtil.encode(text, "D:\\cloudfish\\app\\aa.jpg", "d:\\cc\\", "qrcode1", true);
        System.out.println(QRCodeUtil.decode("d:\\cc\\qrcode1.jpg"));
    }
}

最后，测试结果如下：

【20200201】SpringBoot ZXing - 图1
图-1

二维码生成技术学习资料： https://www.aliyun.com/ss/?k=二维码生成 https://yq.aliyun.com/articles/239405?spm=5176.10695662.1996646101.searchclickresult.4b6825c7YBvZu6 https://yq.aliyun.com/articles/131683?spm=5176.10695662.1996646101.searchclickresult.4b6825c7YBvZu6 http://code.google.com/p/zxing/ 开源库api文档：https://zxing.github.io/zxing/apidocs/