zxing开发之二维码

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ZXing是Google开发的用于Java，Android的条形码扫描库。

依赖

<dependency>
  <groupId>com.google.zxing</groupId>
  <artifactId>javase</artifactId>
  <version>3.4.0</version>
</dependency>
<dependency>
  <groupId>com.google.zxing</groupId>
  <artifactId>core</artifactId>
  <version>3.4.0</version>
</dependency>

代码

package com.yetech.hello.util;

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.MatrixToImageConfig;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.geom.RoundRectangle2D;
import java.awt.image.BufferedImage;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.LinkedHashMap;
import java.util.Map;

/**
 * 参考 https://www.wetools.com/qrcode
 */
public class QrCodeUtil {

    // 二维码内容
    private String content;
    // 二维码大小-宽
    private int qrWidth;
    // 二维码大小-高
    private int qrHeight;
    // 二维码边框-内边距
    private int qrMargin = 0;
    // 二维码前景色
    private Color onColor = new Color(0, 0, 0);
    // 二维码背景色
    private Color offColor = new Color(255, 255, 255);
    // Logo
    private InputStream logoPath;
    // Logo 边框宽度
    private int logoBorder = 0;
    // Logo 边框背景色
    private Color logoBorderColor = Color.WHITE;
    // Logo 圆角大小
    private int logoRoundCorner = 0;

    // 属性
    private Map<EncodeHintType, Object> hints;

    public static QrCodeUtil Builder() {
        return new QrCodeUtil();
    }

    public QrCodeUtil setHints(Map<EncodeHintType, Object> hints) {
        this.hints = hints;
        return this;
    }

    public QrCodeUtil setContent(String content) {
        this.content = content;
        return this;
    }

    public QrCodeUtil setSize(int width, int height) {
        this.qrWidth = width;
        this.qrHeight = height;
        return this;
    }

    public QrCodeUtil setColor(Color onColor, Color offColor) {
        this.onColor = onColor;
        this.offColor = offColor;
        return this;
    }

    public QrCodeUtil setMargin(int margin) {
        this.qrMargin = margin;
        return this;
    }

    public QrCodeUtil setLogo(FileInputStream logoPath) {
        this.logoPath = logoPath;
        return this;
    }

    public QrCodeUtil setLogoBorder(int logoBorder, Color logoBorderColor) {
        this.logoBorder = logoBorder;
        this.logoBorderColor = logoBorderColor;
        return this;
    }

    public QrCodeUtil setLogoRoundCorner(int logoRoundCorner) {
        this.logoRoundCorner = logoRoundCorner;
        return this;
    }

    // 创建二维码  ImageIO.write(bufferedImage, "png", outFile);
    public BufferedImage create() throws WriterException {
        try {
            if (this.hints == null) {
                this.hints = new LinkedHashMap<>(3);
                //设置容错等级
                this.hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
                //定义字符集，我们设置为utf-8
                this.hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
                //设置边距，二维码边距空白宽度为0
                this.hints.put(EncodeHintType.MARGIN, 0);
            }
            // 添加 hintType
            BufferedImage bufferedImage = this.getBufferedImage(this.hints);
            // 添加 logo
            this.drawLogo(bufferedImage);
            // 生成二维码图片
            return bufferedImage;
        } catch (WriterException e) {
            System.out.println("生成二维码异常:" + e.getMessage());
            throw new WriterException(e);
        }
    }

    private void drawLogo(BufferedImage image) {
        if (this.logoPath != null) {
            // 读取二维码图片，并构建绘图对象
            Graphics2D graphics2D = image.createGraphics();
            int imageWidth = image.getWidth(), imageHeight = image.getHeight();
            // 设置消除锯齿
            graphics2D.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
            graphics2D.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP));
            try {
                // 读取logo图片
                BufferedImage logo = ImageIO.read(this.logoPath);
                // 设置logo的大小,设置为二维码图片的20%,因为过大会盖掉二维码
                int logoWidth = logo.getWidth(null) > imageWidth * 3 / 10 ? (imageWidth * 3 / 10) : logo.getWidth(null);
                int logoHeight = logo.getHeight(null) > imageHeight * 3 / 10 ? (imageHeight * 3 / 10) : logo.getWidth(null);
                // 定义logo位置x,y 放在中心,
                int x = (imageWidth - logoWidth) / 2, y = (imageHeight - logoHeight) / 2;
                // 设置logo 有一道边框 宽度（其实就是画一块贴面）
                graphics2D.setStroke(new BasicStroke(this.logoBorder, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
                // logo边框颜色
                graphics2D.setColor(this.logoBorderColor);
                // logo边框弧形
                graphics2D.draw(new RoundRectangle2D.Float(x, y, logoWidth, logoHeight, this.logoRoundCorner, this.logoRoundCorner));
                // 绘制LOGO圆弧矩形
                graphics2D.setClip(new RoundRectangle2D.Float(x, y, logoWidth, logoHeight, this.logoRoundCorner, this.logoRoundCorner));
                // 开始绘制LOGO到二维码上
                graphics2D.drawImage(logo, x, y, logoWidth, logoHeight, null);
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                //释放资源
                graphics2D.dispose();
            }
        }
    }

    // 绘制二维码图片流
    private BufferedImage getBufferedImage(Map<EncodeHintType, Object> hints) throws WriterException {
        // 生成矩阵
        BitMatrix bitMatrix = new MultiFormatWriter().encode(this.content, BarcodeFormat.QR_CODE, this.qrWidth, this.qrHeight, hints);
        // 更新白边边框 让生成的二维码在图片属性上跟我们设置的图片大小size一致
        BitMatrix bitMatrixUpdate = this.updateBitMatrix(bitMatrix, this.qrMargin);
        // 是否设置二维码背景色/前景色
        MatrixToImageConfig matrixToImageConfig = new MatrixToImageConfig(this.onColor.getRGB(), this.offColor.getRGB());
        // 生成二维码对象
        int matrixUpdateWidth = bitMatrixUpdate.getWidth(), matrixUpdateHeight = bitMatrixUpdate.getHeight();
        BufferedImage bufferedImage = new BufferedImage(matrixUpdateWidth, matrixUpdateHeight, BufferedImage.TYPE_INT_ARGB);
        for (int x = 0; x < matrixUpdateWidth; x++) {
            for (int y = 0; y < matrixUpdateHeight; y++) {
                bufferedImage.setRGB(x, y, bitMatrixUpdate.get(x, y) ? matrixToImageConfig.getPixelOnColor() : matrixToImageConfig.getPixelOffColor());
            }
        }
        // 根据size放大、缩小生成的二维码
        BufferedImage newImage = new BufferedImage(this.qrWidth, this.qrHeight, bufferedImage.getType());
        Graphics g = newImage.getGraphics();
        g.drawImage(bufferedImage, 0, 0, this.qrWidth, this.qrHeight, null);
        g.dispose();
        return newImage;
    }

    // 因为二维码边框设置那里不起作用，不管设置多少，都会生成白边，所以需要自定义控制白边宽度，
    // 该方法生成自定义白边框后的bitMatrix
    private BitMatrix updateBitMatrix(BitMatrix matrix, int margin) {
        int tempM = margin * 2;
        int[] rec = matrix.getEnclosingRectangle(); // 获取二维码图案的属性
        int resWidth = rec[2] + tempM;
        int resHeight = rec[3] + tempM;
        BitMatrix resMatrix = new BitMatrix(resWidth, resHeight); // 按照自定义边框生成新的BitMatrix
        resMatrix.clear();
        for (int i = margin; i < resWidth - margin; i++) { // 循环，将二维码图案绘制到新的bitMatrix中
            for (int j = margin; j < resHeight - margin; j++) {
                if (matrix.get(i - margin + rec[0], j - margin + rec[1])) {
                    resMatrix.set(i, j);
                }
            }
        }
        return resMatrix;
    }
}

生成

普通二维码

Map<EncodeHintType, Object> hints = new LinkedHashMap<>();
hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
//定义字符集，我们设置为utf-8
hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
ImageIO.write(QrCodeUtil.Builder().setContent("普通二维码")
        .setSize(300, 300)
        .setHints(hints)
        .create(), "png", new File("E:\\qrcode\\zxingNormal.png"));

彩色二维码

// 设置颜色1
ImageIO.write(QrCodeUtil.Builder().setContent("黑白二维码")
        .setSize(300, 300)
        .setColor(new Color(0, 0, 0), new Color(255, 255, 255))
        .create(), "png", new File("E:\\qrcode\\zxingNorma2.png"));
// 设置颜色2
ImageIO.write(QrCodeUtil.Builder().setContent("彩色二维码")
        .setSize(300, 300)
        .setColor(new Color(255, 0, 0), new Color(0, 0, 255))
        .create(), "png", new File("E:\\qrcode\\zxingNorma3.png"));

LOGO二维码

ImageIO.write(QrCodeUtil.Builder().setContent("LOGO二维码")
        .setSize(300, 300).setMargin(0)
        .setLogo(new FileInputStream(new File("E:\\qrcode\\logo.png")))
        .setLogoBorder(10, Color.RED).setLogoRoundCorner(10)
        .create(), "png", new File("E:\\qrcode\\zxingNorma4.png"));