java生成二维码

1.pom文件添加maven依赖：

        <!-- 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>

2.生成二维码工具类：

package com.xzp.utils;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.util.Hashtable;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import com.lhtc.jv.config.Constants;

public class QrCodeUtil {
    
    private static final String FORMAT_NAME = "jpg";
    // 二维码尺寸
    private static final int QRCODE_SIZE = 300;

    public static InputStream creatImage(String content) throws Exception {
        Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
        hints.put(EncodeHintType.CHARACTER_SET, Constants.DEFAULT_URL_ENCODING);
        BitMatrix bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, QRCODE_SIZE, QRCODE_SIZE,
                hints);
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        MatrixToImageWriter.writeToStream(bitMatrix, FORMAT_NAME, out);
        return new ByteArrayInputStream(out.toByteArray());
    }
    
}