ZXing 生成二维码

ZXing的解释：

zxing和java，引入jar包

<!-- 谷歌二维码生成jar -->
			<!-- https://mvnrepository.com/artifact/com.google.zxing/core -->
			<dependency>
				<groupId>com.google.zxing</groupId>
				<artifactId>core</artifactId>
				<version>3.4.0</version>
			</dependency>
			<!-- https://mvnrepository.com/artifact/com.google.zxing/javase -->
			<dependency>
				<groupId>com.google.zxing</groupId>
				<artifactId>javase</artifactId>
				<version>3.4.0</version>
			</dependency>

生成二维码字节

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.qrcode.QRCodeWriter;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;

import java.io.ByteArrayOutputStream;
import java.util.HashMap;
import java.util.Map;

/**
 * 谷歌二维码生成工具类
 */
public class ZXingUtils {

    /**
     * 生成字节码
     *
     * @param text
     * @param width
     * @param height
     * @return
     * @throws Exception
     */
    public static byte[] getQRCodeImage(String text, int width, int height) throws Exception {
        Map<EncodeHintType, Object> hints = new HashMap<>();
        //排错率  L<M<Q<H
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
        //编码
        hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
        //外边距：margin
        hints.put(EncodeHintType.MARGIN, 0);
        QRCodeWriter qrCodeWriter = new QRCodeWriter();
        // 第一个参数是内容，或者网址，第二个参数是生成的类型，当前类型是二维码，也可以是条形码，后面是长度宽度，最后是声明的参数map
        BitMatrix bitMatrix = qrCodeWriter.encode(text, BarcodeFormat.QR_CODE, width, height, hints);
        ByteArrayOutputStream pngOutputStream = new ByteArrayOutputStream();
        // 使用此方法保存至输出流中
        MatrixToImageWriter.writeToStream(bitMatrix, "PNG", pngOutputStream);
        //获取内存缓冲区中的数据
        return pngOutputStream.toByteArray();
    }

}