生成二维码
工具类来源网络
<!-- 二维码 -->
<dependency>
<groupId>com.google.zxing</groupId>
<artifactId>javase</artifactId>
<version>3.1.0</version>
</dependency>
<!-- 使用了Base64 -->
<dependency>
<groupId>commons-codec</groupId>
<artifactId>commons-codec</artifactId>
<version>1.10</version>
</dependency>
生成二维码工具类
package com.dem.common.utils;
import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
import org.apache.commons.codec.binary.Base64;
import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.util.HashMap;
import java.util.Map;
/**
* @author lichangben
* @date 2021/8/5
*/
public class QRCodeUtils {
// 默认是黑色
private static final int QRCOLOR = 0xFF000000;
// 背景颜色
private static final int BGWHITE = 0xFFFFFFFF;
// 二维码宽
private static final int WIDTH = 400;
// 二维码高
private static final int HEIGHT = 400;
// 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;
{
// 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.ERROR_CORRECTION, ErrorCorrectionLevel.H);
// 设置编码方式
put(EncodeHintType.CHARACTER_SET, "utf-8");
put(EncodeHintType.MARGIN, 0);
}
};
/**
* 生成带logo的二维码图片
* note 二维码下方的标题，如果不需要为空即可
* 返回字符串，将此字符串放入IMG标签的SRC即可
*/
public static String drawLogoQRCode(String qrUrl, String logoUrl,String note) {
//logUrl 存放的绝对路径，如果存放在本项目的resource底下，可以用 某个类.class.getResource("/xxx.png").getPath()来获取
File logoFile = new File(logoUrl);
BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);
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);
// 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) ? QRCOLOR : BGWHITE);
}
}
int width = image.getWidth();
int height = image.getHeight();
if ( 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();
//写入输出流，用于转换
ByteArrayOutputStream tmp = new ByteArrayOutputStream();
ImageIO.write(image, "png", tmp);
tmp.close();
return "data:image/png;base64,"+(new String(Base64.encodeBase64(tmp.toByteArray())));
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
/**
* 生成不带logo的二维码图片
* note 二维码下方的标题，如果不需要为空即可
* 返回字符串，将此字符串放入IMG标签的SRC即可
*/
public static String drawLogoQRCodeNotLogo(String qrUrl, String note) {
BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);
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);
// 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) ? QRCOLOR : BGWHITE);
}
}
int height = image.getHeight();
// 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();
//写入缓存区，用于转换
ByteArrayOutputStream tmp = new ByteArrayOutputStream();
ImageIO.write(image, "png", tmp);
tmp.close();
return "data:image/png;base64,"+(new String(Base64.encodeBase64(tmp.toByteArray())));
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
}
::: tip 提示
前端生成二维码 使用qrcode.js
qrcode.js 下载
:::