Bootstrap

java生成文字二维码、url二维码

pom:

        <dependency>
            <groupId>com.google.zxing</groupId>
            <artifactId>core</artifactId>
            <version>3.3.3</version>
        </dependency>

1)生成文字二维码

java工具类:

package com.ruoyi.common.utils.file;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.common.BitMatrix;
import com.ruoyi.common.exception.ServiceException;
import com.ruoyi.common.utils.StringUtils;
import lombok.extern.slf4j.Slf4j;

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.nio.charset.StandardCharsets;

/**
 * 文字生成二维码
 */
@Slf4j
public class GenerateQrCodeFile {
    /**
     * 黑
     */
    private static final int BLACK = 0xFF000000;
    /**
     * 白
     */
    private static final int WHITE = 0xFFFFFFFF;
    /**
     * 高
     */
    private static final int HIGTH = 300;
    /**
     * 宽
     */
    private static final int WIDTH = 300;
    /**
     * 文件后缀
     */
    private static final String FORMAT = "jpg";
    private static final String DOT = ".";

    /**
     * 字符串生成二维码方法
     *
     * @param content 字符串
     * @return 二维码
     */
    public static File buildQuickMark(String content, String filePath) {
        File file = new File(filePath + File.separator + content + DOT + FORMAT);
        try {
            if (!file.exists()) {
                file.mkdirs();
            }
            BitMatrix byteMatrix = new MultiFormatWriter().encode(new String(content.getBytes(), StandardCharsets.ISO_8859_1),
                    BarcodeFormat.QR_CODE, WIDTH, HIGTH);
            BufferedImage image = toBufferedImage(byteMatrix);
            if (!ImageIO.write(image, FORMAT, file)) {
                throw new IOException("生成二维码异常" + file);
            }
            return file;
        } catch (Exception e) {
            log.error("生成二维码异常", e);
            throw new ServiceException("生成二维码异常");
        }
    }

    private static BufferedImage toBufferedImage(BitMatrix matrix) {
        int width = matrix.getWidth();
        int height = matrix.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, matrix.get(x, y) ? BLACK : WHITE);
            }
        }
        return image;
    }

    /**
     * 上传二维码
     *
     * @param content 二维码内容
     * @param path    路径
     */
    public static String uploadImage(String content, String path) {
        if (StringUtils.isBlank(content) || StringUtils.isBlank(path)) {
            throw new ServiceException("新增二维码图片异常!");
        }
        try {
            // 生成二维码图片
            GenerateQrCodeFile.buildQuickMark(content, path);
            return content + DOT + FORMAT;
        } catch (Exception e) {
            throw new ServiceException("新增二维码图片异常!");
        }
    }
}

2)url地址生成二维码

java工具类:

package com.ruoyi.common.utils;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.WriterException;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.imageio.ImageIO;
import javax.swing.filechooser.FileSystemView;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.Map;

/**
 * 二维码工具
 **/
public class QRCodeUtil {
    private static final Logger log= LoggerFactory.getLogger(QRCodeUtil.class);

    //CODE_WIDTH:二维码宽度,单位像素
    private static final int CODE_WIDTH = 400;
    //CODE_HEIGHT:二维码高度,单位像素
    private static final int CODE_HEIGHT = 400;
    //FRONT_COLOR:二维码前景色,0x000000 表示黑色
    private static final int FRONT_COLOR = 0x000000;
    //BACKGROUND_COLOR:二维码背景色,0xFFFFFF 表示白色
    //演示用 16 进制表示,和前端页面 css 的取色是一样的,注意前后景颜色应该对比明显,如常见的黑白
    private static final int BACKGROUND_COLOR = 0xFFFFFF;

    /**
     * 生成二维码
     * 
     * @param content            二维码跳转地址
     * @param codeImgFileSaveDir 放存储路径的File类
     * @param fileName           二维码图片名称(包含后缀)
     */
    public static void createCodeToFile(String content, File codeImgFileSaveDir, String fileName) {
        try {
            if (StringUtils.isBlank(content) || StringUtils.isBlank(fileName)) {
                return;
            }
            content = content.trim();
            if (codeImgFileSaveDir==null || codeImgFileSaveDir.isFile()) {
                //二维码图片存在目录为空,默认放在桌面...
                codeImgFileSaveDir = FileSystemView.getFileSystemView().getHomeDirectory();
            }
            if (!codeImgFileSaveDir.exists()) {
                //二维码图片存在目录不存在,开始创建...
                codeImgFileSaveDir.mkdirs();
            }

            //核心代码-生成二维码
            BufferedImage bufferedImage = getBufferedImage(content);

            File codeImgFile = new File(codeImgFileSaveDir, fileName);
            ImageIO.write(bufferedImage, "png", codeImgFile);

            log.info("二维码图片生成成功:" + codeImgFile.getPath());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 生成二维码并输出到输出流, 通常用于输出到网页上进行显示,输出到网页与输出到磁盘上的文件中,区别在于最后一句 ImageIO.write
     * write(RenderedImage im,String formatName,File output):写到文件中
     * write(RenderedImage im,String formatName,OutputStream output):输出到输出流中
     * @param content :二维码内容
     * @param outputStream :输出流,比如 HttpServletResponse 的 getOutputStream
     */
    public static void createCodeToOutputStream(String content, OutputStream outputStream) {
        try {
            if (StringUtils.isBlank(content)) {
                return;
            }
            content = content.trim();
            //核心代码-生成二维码
            BufferedImage bufferedImage = getBufferedImage(content);

            //区别就是这一句,输出到输出流中,如果第三个参数是 File,则输出到文件中
            ImageIO.write(bufferedImage, "png", outputStream);

            log.info("二维码图片生成到输出流成功...");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    //核心代码-生成二维码
    private static BufferedImage getBufferedImage(String content) throws WriterException {

        //com.google.zxing.EncodeHintType:编码提示类型,枚举类型
        Map<EncodeHintType, Object> hints = new HashMap();

        //EncodeHintType.CHARACTER_SET:设置字符编码类型
        hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");

        //EncodeHintType.ERROR_CORRECTION:设置误差校正
        //ErrorCorrectionLevel:误差校正等级,L = ~7% correction、M = ~15% correction、Q = ~25% correction、H = ~30% correction
        //不设置时,默认为 L 等级,等级不一样,生成的图案不同,但扫描的结果是一样的
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.M);

        //EncodeHintType.MARGIN:设置二维码边距,单位像素,值越小,二维码距离四周越近
        hints.put(EncodeHintType.MARGIN, 1);

        MultiFormatWriter multiFormatWriter = new MultiFormatWriter();
        BitMatrix bitMatrix = multiFormatWriter.encode(content, BarcodeFormat.QR_CODE, CODE_WIDTH, CODE_HEIGHT, hints);
        BufferedImage bufferedImage = new BufferedImage(CODE_WIDTH, CODE_HEIGHT, BufferedImage.TYPE_INT_BGR);
        for (int x = 0; x < CODE_WIDTH; x++) {
            for (int y = 0; y < CODE_HEIGHT; y++) {
                bufferedImage.setRGB(x, y, bitMatrix.get(x, y) ? FRONT_COLOR : BACKGROUND_COLOR);
            }
        }
        return bufferedImage;
    }
}

;