title: java 生成二维码
date: 16:23 2018/8/23

java 生成普通的二维码

话不多说，直接上代码

源码地址： https://github.com/pnunu/design-pattern/tree/master/src/main/java/pnunu/QRcode

pom 文件

<dependency>
    <groupId>com.google.zxing</groupId>
    <artifactId>core</artifactId>
    <version>3.2.1</version>
</dependency>
<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-lang3</artifactId>
    <version>3.8</version>
</dependency>

QrCodeCreateUtil.java

package pnunu.QRcode;

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.apache.commons.lang3.StringUtils;

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

/**
 * @Author: pnunu
 * @Date: Created in 14:38 2018/8/23
 * @Description: 二维码的生成
 */
public class QrCodeCreateUtil {
    private static final int QR_COLOR = 0xFF000000; // 默认是黑色
    private static final int BG_WHITE = 0xFFFFFFFF; // 背景颜色

    private static final int WIDTH = 400; // 二维码宽
    private static final int HEIGHT = 400; // 二维码高

    // 用于设置QR二维码参数
    private static Map<EncodeHintType, Object> hints = new HashMap<EncodeHintType, Object>() {
        private static final long serialVersionUID = 1L;

        {
            put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);// 设置QR二维码的纠错级别（H为最高级别）具体级别信息
            put(EncodeHintType.CHARACTER_SET, "utf-8");// 设置编码方式
            put(EncodeHintType.MARGIN, 0);
        }
    };

    public static void main(String[] args) throws WriterException {
        File logoFile = new File("img/logo.png");
        File qrCodeFile = new File("img/pnunu.png");
        String url = "http://pnunu.cn/";
        String note = "小小暮雨";
        drawLogoQRCode(logoFile, qrCodeFile, url, note);
    }

    // 生成带logo的二维码图片
    public static void drawLogoQRCode(File logoFile, File codeFile, String qrUrl, String note) {
        try {
            MultiFormatWriter multiFormatWriter = new MultiFormatWriter();
            // 参数顺序分别为：编码内容，编码类型，生成图片宽度，生成图片高度，设置参数
            BitMatrix bm = multiFormatWriter.encode(qrUrl, BarcodeFormat.QR_CODE, WIDTH, HEIGHT, hints);
            BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);

            // 开始利用二维码数据创建Bitmap图片，分别设为黑（0xFFFFFFFF）白（0xFF000000）两色
            for (int x = 0; x < WIDTH; x++) {
                for (int y = 0; y < HEIGHT; y++) {
                    image.setRGB(x, y, bm.get(x, y) ? QR_COLOR : BG_WHITE);
                }
            }

            int width = image.getWidth();
            int height = image.getHeight();
            if (Objects.nonNull(logoFile) && logoFile.exists()) {
                // 构建绘图对象
                Graphics2D g = image.createGraphics();
                // 读取Logo图片
                BufferedImage logo = ImageIO.read(logoFile);
                // 开始绘制logo图片
                g.drawImage(logo, width * 2 / 5, height * 2 / 5, width * 2 / 10, height * 2 / 10, null);
                g.dispose();
                logo.flush();
            }

            // 自定义文本描述
            if (StringUtils.isNotEmpty(note)) {
                // 新的图片，把带logo的二维码下面加上文字
                BufferedImage outImage = new BufferedImage(400, 445, BufferedImage.TYPE_4BYTE_ABGR);
                Graphics2D outg = outImage.createGraphics();
                // 画二维码到新的面板
                outg.drawImage(image, 0, 0, image.getWidth(), image.getHeight(), null);
                // 画文字到新的面板
                outg.setColor(Color.BLACK);
                outg.setFont(new Font("楷体", Font.BOLD, 30)); // 字体、字型、字号
                int strWidth = outg.getFontMetrics().stringWidth(note);
                if (strWidth > 399) {
                    // //长度过长就截取前面部分
                    // 长度过长就换行
                    String note1 = note.substring(0, note.length() / 2);
                    String note2 = note.substring(note.length() / 2, note.length());
                    int strWidth1 = outg.getFontMetrics().stringWidth(note1);
                    int strWidth2 = outg.getFontMetrics().stringWidth(note2);
                    outg.drawString(note1, 200 - strWidth1 / 2, height + (outImage.getHeight() - height) / 2 + 12);
                    BufferedImage outImage2 = new BufferedImage(400, 485, BufferedImage.TYPE_4BYTE_ABGR);
                    Graphics2D outg2 = outImage2.createGraphics();
                    outg2.drawImage(outImage, 0, 0, outImage.getWidth(), outImage.getHeight(), null);
                    outg2.setColor(Color.BLACK);
                    outg2.setFont(new Font("宋体", Font.BOLD, 30)); // 字体、字型、字号
                    outg2.drawString(note2, 200 - strWidth2 / 2, outImage.getHeight() + (outImage2.getHeight() - outImage.getHeight()) / 2 + 5);
                    outg2.dispose();
                    outImage2.flush();
                    outImage = outImage2;
                } else {
                    outg.drawString(note, 200 - strWidth / 2, height + (outImage.getHeight() - height) / 2 + 12); // 画文字
                }
                outg.dispose();
                outImage.flush();
                image = outImage;
            }

            image.flush();

            ImageIO.write(image, "png", codeFile); // TODO
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

}