Java ZXing 生成與解析二維碼完整指南

依賴

<dependency>
    <groupId>com.google.zxing</groupId>
    <artifactId>core</artifactId>
    <version>3.5.2</version>
</dependency>
<dependency>
    <groupId>com.google.zxing</groupId>
    <artifactId>javase</artifactId>
    <version>3.5.2</version>
</dependency>

生成二維碼

import com.google.zxing.*;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import java.io.File;
import java.util.HashMap;
import java.util.Map;

public class QRCodeUtil {
    public static void generate(String content, String path, int width, int height) throws Exception {
        Map<EncodeHintType, Object> hints = new HashMap<>();
        hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
        hints.put(EncodeHintType.MARGIN, 1); // 邊距

        BitMatrix matrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, width, height, hints);
        MatrixToImageWriter.writeToPath(matrix, "PNG", new File(path).toPath());
    }

    public static void main(String[] args) throws Exception {
        generate("https://example.com?id=123", "qrcode.png", 300, 300);
    }
}

解析二維碼

import com.google.zxing.*;
import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
import com.google.zxing.common.HybridBinarizer;
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.util.HashMap;
import java.util.Map;

public class QRCodeReader {
    public static String decode(String imagePath) throws Exception {
        BufferedImage image = ImageIO.read(new File(imagePath));
        LuminanceSource source = new BufferedImageLuminanceSource(image);
        BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));

        Map<DecodeHintType, Object> hints = new HashMap<>();
        hints.put(DecodeHintType.CHARACTER_SET, "UTF-8");

        Result result = new MultiFormatReader().decode(bitmap, hints);
        return result.getText();
    }

    public static void main(String[] args) throws Exception {
        System.out.println(decode("qrcode.png"));
    }
}

核心類說明

常見參數調優

• EncodeHintType.ERROR_CORRECTION：L/M/Q/H 四級糾錯，默認 L。
• EncodeHintType.MARGIN：靜默區邊距，默認 4，掃碼困難可調小。
• DecodeHintType.TRY_HARDER：投入更多 CPU 嘗試解碼複雜圖片。