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SpringBoot中生成二維碼的案例分享

更新時(shí)間：2024年08月22日 09:44:26 作者：碼到三十五

在Spring?Boot項(xiàng)目中整合ZXing庫來生成二維碼是一個(gè)常見的需求,zxing是一個(gè)功能強(qiáng)大的開源Java庫,專門用于二維碼的生成與解析,它支持Android、iOS、Java等多個(gè)平臺,本文小編將給大家分享SpringBoot中生成二維碼的案例,需要的朋友可以參考下

引言

在Spring Boot項(xiàng)目中整合ZXing庫來生成二維碼是一個(gè)常見的需求。

zxing，全稱"Zebra Crossing"，是一個(gè)功能強(qiáng)大的開源Java庫，專門用于二維碼的生成與解析。它不僅能夠生成QR碼，還能解析包括QR碼在內(nèi)的多種二維碼格式。ZXing提供了多語言API，使得開發(fā)者能夠輕松地將二維碼功能集成到各種應(yīng)用中。它支持Android、iOS、Java等多個(gè)平臺，并且除了QR碼，還能解析其他一維碼和二維碼，如EAN、UPC、DataMatrix等。

1. 添加zxing庫的依賴

<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>

2. 生成二維碼

創(chuàng)建一個(gè)SpringBoot服務(wù)類QRCodeService，用于生成二維碼圖片：

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.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
import org.springframework.stereotype.Service;

import java.io.IOException;
import java.nio.file.FileSystems;
import java.nio.file.Path;
import java.util.HashMap;
import java.util.Map;

@Service
public class QRCodeService {

    public void generateQRCodeImage(String text, int width, int height, String filePath)
            throws IOException {
        Map<EncodeHintType, Object> hints = new HashMap<>();
        hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.M);
        hints.put(EncodeHintType.MARGIN, 2);

        BitMatrix bitMatrix = new MultiFormatWriter().encode(text, BarcodeFormat.QR_CODE, width, height, hints);

        Path path = FileSystems.getDefault().getPath(filePath);
        MatrixToImageWriter.writeToPath(bitMatrix, "PNG", path);
    }
}

3. 調(diào)用二維碼服務(wù)

3.1 將二維碼圖拍你保存

最后在SpringBoot的Controller中調(diào)用這個(gè)服務(wù)：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.io.IOException;

@RestController
public class QRCodeController {

    @Autowired
    private QRCodeService qrCodeService;

    @GetMapping("/generateQRCode")
    public String generateQRCode(@RequestParam String text, @RequestParam int width, @RequestParam int height) {
        try {
            qrCodeService.generateQRCodeImage(text, width, height, "myqrcode.png");
            return "QR Code generated successfully!";
        } catch (IOException e) {
            return "QR Code generation failed: " + e.getMessage();
        }
    }
}

當(dāng)訪問/generateQRCode端點(diǎn)并傳遞text、width和height參數(shù)時(shí)，它將生成一個(gè)名為myqrcode.png的二維碼圖片并保存到項(xiàng)目根目錄下。

http://localhost:8080/generateQRCode?text=Hello,World!&width=350&height=350

3.2 直接返回二維碼圖片

修改QRCodeController來返回二維碼圖片：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.io.ByteArrayResource;
import org.springframework.core.io.Resource;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import javax.imageio.ImageIO;

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;

@RestController
public class QRCodeController {

    @GetMapping("/generateQRCode")
    public ResponseEntity<Resource> generateQRCode(@RequestParam String text, @RequestParam Integer width, @RequestParam Integer  height) throws IOException {
        BitMatrix bitMatrix = new MultiFormatWriter().encode(text, BarcodeFormat.QR_CODE, width, height, getHints());

        BufferedImage qrCodeImage = MatrixToImageWriter.toBufferedImage(bitMatrix);
        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
        ImageIO.write(qrCodeImage, "PNG", byteArrayOutputStream);

        byte[] qrCodeBytes = byteArrayOutputStream.toByteArray();

        HttpHeaders headers = new HttpHeaders();
        headers.add(HttpHeaders.CONTENT_TYPE, MediaType.IMAGE_PNG_VALUE);

        return ResponseEntity.ok()
                .headers(headers)
                .contentLength(qrCodeBytes.length)
                .body(new ByteArrayResource(qrCodeBytes));
    }

    private Map<EncodeHintType, Object> getHints() {
        Map<EncodeHintType, Object> hints = new HashMap<>();
        hints.put(EncodeHintType.CHARACTER_SET, "UTF-8");
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.M);
        hints.put(EncodeHintType.MARGIN, 2);
        return hints;
    }
}

generateQRCode先生成二維碼的BitMatrix，然后轉(zhuǎn)換為BufferedImage，以便獲取二維碼圖片的字節(jié)流。

3.2 注冊BufferedImage消息轉(zhuǎn)換器返回圖片

3.2中返回圖片也可以通過注冊一個(gè)SpringBoot的消息轉(zhuǎn)換器來實(shí)現(xiàn):

@Bean
 public HttpMessageConverter<BufferedImage> createImageHttpMessageConverter() {
  return new BufferedImageHttpMessageConverter();
 }

返回圖片

package com.example.demo.controller;

import java.awt.image.BufferedImage;

import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

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

@RestController
@RequestMapping("/qr")
public class QrCodeController {

 @GetMapping(value = "/{barcode}", produces = MediaType.IMAGE_PNG_VALUE)
 public ResponseEntity<BufferedImage> barbecueEAN13Barcode(@PathVariable("barcode") String barcode)
   throws Exception {

  QRCodeWriter barcodeWriter = new QRCodeWriter();
     BitMatrix bitMatrix = 
       barcodeWriter.encode(barcode, BarcodeFormat.QR_CODE, 200, 200);

  return new ResponseEntity<>(MatrixToImageWriter.toBufferedImage(bitMatrix),HttpStatus.OK);
 }

}

現(xiàn)在，當(dāng)訪問/qr端點(diǎn)時(shí)，將直接收到一個(gè)二維碼圖片作為響應(yīng)。