使用 Qrcode 生成中间带 logo 的二维码！

可以自由定义生成的二维码中间是否带 logo ！

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package com.controller;
 
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
 
import javax.imageio.ImageIO;
 
import com.entity.CodeImage;
import com.swetake.util.Qrcode;
 
import jp.sourceforge.qrcode.QRCodeDecoder;
import jp.sourceforge.qrcode.exception.DecodingFailedException;
 
/**
 * @author Mongo
 */
public class QrCode {
 
    /**
     * 生成二维码(QRCode)图片
     * 
     * @param flag （是否带中间logo）
     */
    public static void createQRCode(Boolean flag) {
        try {
             
        //================基本信息==============================================
             
            /* 要合成的两张图片 */
            String logoPath = "D:/logo.png";//中间logo图片
            String qrcodePath = "D:/qrcode.png";//二维码图片
             
            /* 二维码种要存储的信息！（没有的话，二维码不展示！） */
            String content = "您的设备已经中毒了，请注意！请注意！";
             
            /* 合成的二维码的一些特性 */
            String format = "png";//图片的格式
            char correct = 'H';// 容错率
            char mode = 'B';// 类型
            int version = 10;// 版本（亦能决定合成后的二维码大小）
 
            /* 合成后的二维码的宽与高 */
            int width = 178;
            int height = 178;
             
        //===================================================================== 
             
            Qrcode qrcodeHandler = new Qrcode();
            /* 设置二维码排错率，可选L(7%)、M(15%)、Q(25%)、H(30%)，排错率越高可存储的信息越少，但对二维码清晰度的要求越小 */
            qrcodeHandler.setQrcodeErrorCorrect(correct);// 特别注意：这里使用单引号！！ 属于 char 类型，不是 String 类型
            /* N代表数字,A代表字符a-Z,B代表其他字符 */
            qrcodeHandler.setQrcodeEncodeMode(mode);
            /* 设置设置二维码版本，取值范围1-40，值越大尺寸越大，可存储的信息越大 */
            qrcodeHandler.setQrcodeVersion(version);
 
            /* 内容 byte 化 */
            byte[] contentBytes = content.getBytes("UTF-8");
 
            BufferedImage bufImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
 
            Graphics2D gs = bufImg.createGraphics();
            gs.setBackground(Color.WHITE);
            gs.clearRect(0, 0, width, height);//没有这个，二维码全黑
 
            /* 设置图像颜色 */
            gs.setColor(Color.BLACK);
 
            /* 设置偏移量 不设置可能导致解析出错 */
            int pixoff = 2;//中间logo偏移大小
            /* 输出内容 > 二维码 */
            if (contentBytes.length > 0 && contentBytes.length < width) {
                boolean[][] codeOut = qrcodeHandler.calQrcode(contentBytes);
                for (int i = 0; i < codeOut.length; i++) {
                    for (int j = 0; j < codeOut.length; j++) {
                        if (codeOut[j][i]) {
                            gs.fillRect(j * 3 + pixoff, i * 3 + pixoff, 3, 3);
                        }
                    }
                }
            } else {
                System.err.println("QRCode content bytes length = " + contentBytes.length + " not in [ 0,200]. ");
            }
             
            /* 判断是否需要添加logo图片 */
            if (flag) {
                int width_4 = width / 4;
                int width_8 = width_4 / 2;
                int height_4 = height / 4;
                int height_8 = height_4 / 2;
                Image img = ImageIO.read(new File(logoPath));
                gs.drawImage(img, width_4 + width_8, height_4 + height_8, width_4, height_4, null);
                gs.dispose();
                bufImg.flush();
            }
 
            /* 生成二维码QRCode图片 */
            SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
            String fileName = sdf.format(new Date()) + "." + format;
            String url = qrcodePath + fileName;
            File imgFile = new File(url);
            if (!imgFile.exists()) {
                imgFile.mkdirs();
            }
            ImageIO.write(bufImg, format, imgFile);
            System.out.println("生成二维码图片成功!");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
 
    /**
     * 解析二维码（直接读取二维码信息）
     */
    public static String decode(String imagePath) {
        // QRCode 二维码图片的文件
        File imageFile = new File(imagePath);
        BufferedImage bufImg = null;
        String content = null;
        try {
            bufImg = ImageIO.read(imageFile);
            QRCodeDecoder decoder = new QRCodeDecoder();
            content = new String(decoder.decode(new CodeImage(bufImg)), "utf-8");
        } catch (IOException e) {
            System.out.println("Error: " + e.getMessage());
            e.printStackTrace();
        } catch (DecodingFailedException dfe) {
            System.out.println("Error: " + dfe.getMessage());
            dfe.printStackTrace();
        }
        return content;
    }
 
    public static void main(String[] args) {
         
        Boolean flag = true;//是否添加中间logo!
         
        QrCode.createQRCode(flag);
//       String content = QrCode.decode("D:/xxxx.png");//解析二维码图片
//      System.out.println("结束="+content);
    }
 
}

解析二维码则需要一个实体类：

package com.entity;
 
import java.awt.image.BufferedImage;
 
import jp.sourceforge.qrcode.data.QRCodeImage;
 
/**
* @author Mongo
*/
public class CodeImage implements QRCodeImage {
 
    private BufferedImage bufferedImage;
     
    public CodeImage(BufferedImage image){  
        this.bufferedImage = image;  
    }  
     
    @Override
    public int getHeight() {
        return bufferedImage.getHeight();
    }
 
    @Override
    public int getPixel(int x, int y) {
        return bufferedImage.getRGB(x, y);
    }
 
    @Override
    public int getWidth() {
        return bufferedImage.getHeight();
    }
 
}