Java 生成二维码图片

准备

依赖配置pom

<dependency>
			<groupId>com.google.zxing</groupId>
			<artifactId>core</artifactId>
			<version>3.4.1</version>
</dependency>
<dependency>
			<groupId>com.google.zxing</groupId>
			<artifactId>javase</artifactId>
			<version>3.4.1</version>
</dependency>

生成二维码并嵌入

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.common.BitMatrix;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.util.HashMap;
import java.util.Map;

public class QRCodeWithLogo {
    public static void main(String[] args) throws Exception {
        // 二维码内容
        String content = "hello";
        // 二维码图片宽度
        int width = 300;
        // 二维码图片高度
        int height = 300;
        // 二维码图片格式
        String format = "png";
        // 小图片路径
        String logoPath = "logo.png";
        // 小图片占二维码的比例
        double ratio = 0.2;

        // 定义二维码参数
        MultiFormatWriter writer = new MultiFormatWriter();
        Map<EncodeHintType,Object> hint =new HashMap<>();
        hint.put(EncodeHintType.MARGIN,2);
        BitMatrix matrix = writer.encode(content, BarcodeFormat.QR_CODE, width, height,hint);

        // 加载小图片
        BufferedImage logoImage = ImageIO.read(new File(logoPath));
        int logoWidth = logoImage.getWidth();
        int logoHeight = logoImage.getHeight();

        // 计算小图片在二维码中的位置和大小
        int x = (int) ((width - logoWidth * ratio) / 2);
        int y = (int) ((height - logoHeight * ratio) / 2);
        int w = (int) (logoWidth * ratio);
        int h = (int) (logoHeight * ratio);

        // 创建一个空白的BufferedImage对象，并获取其Graphics2D对象
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        Graphics2D g2d = image.createGraphics();

        // 设置背景色
        g2d.setColor(Color.WHITE);
        g2d.fillRect(0, 0, width, height);
        // 设置前景色
        g2d.setColor(Color.BLACK);

        // 将二维码绘制到空白的BufferedImage对象上
        for (int i = 0; i < width; i++) {
            for (int j = 0; j < height; j++) {
                if (matrix.get(i, j)) {
                    g2d.fillRect(i, j, 1, 1);
                }
            }
        }

        // 将小图片绘制到二维码中央
        g2d.drawImage(logoImage, x, y, w, h, null);

        // 释放资源
        g2d.dispose();

        // 输出二维码图片
        ImageIO.write(image, format, new File("qrcode.png"));
    }
}

生成二维码

import com.google.zxing.BarcodeFormat;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.common.BitMatrix;

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;

public class MyClass {
    public static void main(String[] args) throws Exception {
        // 定义二维码的内容和图片格式
        String content = "Hello, world!";
        String format = "png";

        // 定义二维码的宽度和高度
        int width = 200;
        int height = 200;

        // 定义二维码的参数
        MultiFormatWriter writer = new MultiFormatWriter();
        BitMatrix matrix = writer.encode(content, BarcodeFormat.QR_CODE, width, height);

        // 定义二维码的输出文件
        File outputFile = new File("qrcode.png");

        // 将二维码写入输出文件
        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) ? 0xFF000000 : 0xFFFFFFFF);
            }
        }
        ImageIO.write(image, format, outputFile);

        System.out.println("二维码已生成，文件名为 qrcode.png");
    }
}

利用hutool 生成二维码

import cn.hutool.core.util.IdUtil;
import cn.hutool.extra.qrcode.QrCodeUtil;

import java.io.File;

public class QRCodeDemo {
    public static void main(String[] args) {
        // 二维码内容
        String content = "hello";
        // 二维码文件保存路径
        String filePath = IdUtil.simpleUUID() + ".png";
        // 二维码图片大小
        int width = 300;
        int height = 300;

        // 生成二维码并保存到文件
        QrCodeUtil.generate(content, width, height, new File(filePath));
        System.out.println(filePath);
    }
}