springboot生成二维码到海报模板上

QRCodeController

package com.ruoyi.web.controller.app;

import com.google.zxing.WriterException;
import com.ruoyi.app.domain.Opportunity;
import com.ruoyi.app.tool.QRCodeGenerator;
import com.ruoyi.common.core.page.TableDataInfo;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import io.swagger.annotations.ApiParam;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.servlet.mvc.method.annotation.StreamingResponseBody;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.OutputStream;
import java.util.List;
import java.util.Map;

@RestController
@RequestMapping("/app/qrcCode")
@Api(tags = "推广海报接口")
public class QRCodeController {

    @Autowired
    private QRCodeGenerator qrCodeGenerator;

    @ApiOperation(value = "获取推广海报", notes = "获取推广海报")
    @GetMapping("/qrImage")
    public void generateQRCode(HttpServletResponse response, @RequestParam Map<String, String> params) throws Exception {
        String openid = params.get("openid");
        String xh = params.get("xh");
        if (openid == null || openid.isEmpty()) {
            throw new Exception("openid不能为空");
        }
        if (xh == null || xh.isEmpty()) {
            xh = "1";
        }

		// 改为自己的链接
        String url = "http://*******.cn/app/index/?parentId=" + openid;
        byte[] qrCodeBytes = qrCodeGenerator.generateQRCode(url, 290, 290, xh);

        response.setContentType(MediaType.IMAGE_PNG_VALUE);
        response.setHeader("Content-Disposition", "inline; filename=qrCode.png");
        response.setHeader("Cache-Control", "no-store");
        response.setHeader("Pragma", "no-cache");
        response.setContentLength(qrCodeBytes.length);

        try (OutputStream out = response.getOutputStream()) {
            out.write(qrCodeBytes);
        }
    }
}

QRCodeGenerator

package com.ruoyi.app.tool;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.QRCodeWriter;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
import org.springframework.core.io.ClassPathResource;
import org.springframework.stereotype.Component;

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

@Component
public class QRCodeGenerator {
    public byte[] generateQRCode(String url, int qrCodeWidth, int qrCodeHeight, String xh) throws WriterException, IOException {
        // 生成二维码
        QRCodeWriter qrCodeWriter = new QRCodeWriter();
        Map<EncodeHintType, Object> hints = new HashMap<>();
        hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H); // 设置容错级别为高
        BitMatrix bitMatrix = qrCodeWriter.encode(url, BarcodeFormat.QR_CODE, qrCodeWidth, qrCodeHeight, hints);
        BufferedImage qrCodeImage = bitMatrixToImage(bitMatrix);

        // 加载背景图片
        ClassPathResource backgroundImageResource = new ClassPathResource("static/" + xh + ".jpg");
        BufferedImage backgroundImage = ImageIO.read(backgroundImageResource.getInputStream());

        // 创建包含背景图片的画布
        int combinedImageWidth = backgroundImage.getWidth();
        int combinedImageHeight = backgroundImage.getHeight();
        BufferedImage combinedImage = new BufferedImage(combinedImageWidth, combinedImageHeight, BufferedImage.TYPE_INT_RGB);
        Graphics2D combinedGraphics = combinedImage.createGraphics();
        combinedGraphics.drawImage(backgroundImage, 0, 0, null);

        // 将二维码放在背景图的左下角
        int qrCodeX = 930; // 二维码在背景图片中的X坐标
        int qrCodeY = combinedImageHeight - qrCodeHeight - 20; // 二维码在背景图片中的Y坐标

        // 添加红色边框
        int borderWidth = 2; // 边框宽度
        Color borderColor = Color.decode("#B11E4C"); // 边框颜色
        combinedGraphics.setColor(new Color(borderColor.getRed(), borderColor.getGreen(), borderColor.getBlue(), 0)); // 设置填充颜色为透明色
        combinedGraphics.fillRoundRect(qrCodeX - borderWidth, qrCodeY - borderWidth, qrCodeWidth + 2 * borderWidth, qrCodeHeight + 2 * borderWidth, 5, 5);
        combinedGraphics.setColor(borderColor); // 设置边框颜色
        combinedGraphics.drawRoundRect(qrCodeX - borderWidth, qrCodeY - borderWidth, qrCodeWidth + 2 * borderWidth, qrCodeHeight + 2 * borderWidth, 5, 5); // 绘制边框
        combinedGraphics.drawImage(qrCodeImage, qrCodeX, qrCodeY, null);

        // 将合成的图片转为字节数组
        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        ImageIO.write(combinedImage, "png", byteArrayOutputStream);
        return byteArrayOutputStream.toByteArray();
    }

    private BufferedImage bitMatrixToImage(BitMatrix bitMatrix) {
        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) ? Color.BLACK.getRGB() : Color.WHITE.getRGB());
            }
        }
        return image;
    }
}

海报模板存放（不带二维码的图片）：

把地址放到白名单中，无需token可以访问，然后就得到：