基于SpringBoot生成二维码的几种实现方式

<!-- zxing生成二维码 -->

< dependency >

     < groupId >com.google.zxing</ groupId >

     < artifactId >core</ artifactId >

     < version >3.3.3</ version >

</ dependency >

< dependency >

     < groupId >com.google.zxing</ groupId >

     < artifactId >javase</ artifactId >

     < version >3.3.3</ version >

</ dependency >

/**

  * 二维码工具

  * @Author:debug (SteadyJack)

  * @Link: weixin-> debug0868  qq-> 1948831260

  * @Date: 2020/11/16 22:38

  **/

public class QRCodeUtil {

     private static final Logger log= LoggerFactory.getLogger(QRCodeUtil. class );

     //CODE_WIDTH：二维码宽度，单位像素

     private static final int CODE_WIDTH = 400 ;

     //CODE_HEIGHT：二维码高度，单位像素

     private static final int CODE_HEIGHT = 400 ;

     //FRONT_COLOR：二维码前景色，0x000000 表示黑色

     private static final int FRONT_COLOR = 0x000000 ;

     //BACKGROUND_COLOR：二维码背景色，0xFFFFFF 表示白色

     //演示用 16 进制表示，和前端页面 CSS 的取色是一样的，注意前后景颜色应该对比明显，如常见的黑白

     private static final int BACKGROUND_COLOR = 0xFFFFFF ;

     public static void createCodeToFile(String content, File codeImgFileSaveDir, String fileName) {

         try {

             if (StringUtils.isBlank(content) || StringUtils.isBlank(fileName)) {

                 return ;

             }

             content = content.trim();

             if (codeImgFileSaveDir== null || codeImgFileSaveDir.isFile()) {

                 //二维码图片存在目录为空，默认放在桌面...

                 codeImgFileSaveDir = FileSystemView.getFileSystemView().getHomeDirectory();

             }

             if (!codeImgFileSaveDir.exists()) {

                 //二维码图片存在目录不存在，开始创建...

                 codeImgFileSaveDir.mkdirs();

             }

             //核心代码-生成二维码

             BufferedImage bufferedImage = getBufferedImage(content);

             File codeImgFile = new File(codeImgFileSaveDir, fileName);

             ImageIO.write(bufferedImage, "png" , codeImgFile);

             log.info( "二维码图片生成成功：" + codeImgFile.getPath());

         } catch (Exception e) {

             e.printStackTrace();

         }

     }

     /**

      * 生成二维码并输出到输出流, 通常用于输出到网页上进行显示，输出到网页与输出到磁盘上的文件中，区别在于最后一句 ImageIO.write

      * write(RenderedImage im,String formatName,File output)：写到文件中

      * write(RenderedImage im,String formatName,OutputStream output)：输出到输出流中

      * @param content  ：二维码内容

      * @param outputStream ：输出流，比如 HttpServletResponse 的 getOutputStream

      */

     public static void createCodeToOutputStream(String content, OutputStream outputStream) {

         try {

             if (StringUtils.isBlank(content)) {

                 return ;

             }

             content = content.trim();

             //核心代码-生成二维码

             BufferedImage bufferedImage = getBufferedImage(content);

             //区别就是这一句，输出到输出流中，如果第三个参数是 File，则输出到文件中

             ImageIO.write(bufferedImage, "png" , outputStream);

             log.info( "二维码图片生成到输出流成功..." );

         } catch (Exception e) {

             e.printStackTrace();

         }

     }

     //核心代码-生成二维码

     private static BufferedImage getBufferedImage(String content) throws WriterException {

         //com.google.zxing.EncodeHintType：编码提示类型,枚举类型

         Map<EncodeHintType, Object> hints = new HashMap();

         //EncodeHintType.CHARACTER_SET：设置字符编码类型

         hints.put(EncodeHintType.CHARACTER_SET, "UTF-8" );

         //EncodeHintType.ERROR_CORRECTION：设置误差校正

         //ErrorCorrectionLevel：误差校正等级，L = ~7% correction、M = ~15% correction、Q = ~25% correction、H = ~30% correction

         //不设置时，默认为 L 等级，等级不一样，生成的图案不同，但扫描的结果是一样的

         hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.M);

         //EncodeHintType.MARGIN：设置二维码边距，单位像素，值越小，二维码距离四周越近

         hints.put(EncodeHintType.MARGIN, 1 );

         MultiFormatWriter multiFormatWriter = new MultiFormatWriter();

         BitMatrix bitMatrix = multiFormatWriter.encode(content, BarcodeFormat.QR_CODE, CODE_WIDTH, CODE_HEIGHT, hints);

         BufferedImage bufferedImage = new BufferedImage(CODE_WIDTH, CODE_HEIGHT, BufferedImage.TYPE_INT_BGR);

         for ( int x = 0 ; x < CODE_WIDTH; x++) {

             for ( int y = 0 ; y < CODE_HEIGHT; y++) {

                 bufferedImage.setRGB(x, y, bitMatrix.get(x, y) ? FRONT_COLOR : BACKGROUND_COLOR);

             }

         }

         return bufferedImage;

     }

}

@RequestMapping ( "qr/code" )

public class QrCodeController extends BaseController{

     private static final String RootPath= "E:\\shFiles\\QRCode" ;

     private static final String FileFormat= ".png" ;

     private static final ThreadLocal<SimpleDateFormat> LOCALDATEFORMAT=ThreadLocal.withInitial(() -> new SimpleDateFormat( "yyyyMMddHHmmss" ));

     //生成二维码并将其存放于本地目录

     @PostMapping ( "generate/v1" )

     public BaseResponse generateV1(String content){

         BaseResponse response= new BaseResponse(StatusCode.Success);

         try {

             final String fileName=LOCALDATEFORMAT.get().format( new Date());

             QRCodeUtil.createCodeToFile(content, new File(RootPath),fileName+FileFormat);

         } catch (Exception e){

             response= new BaseResponse(StatusCode.Fail.getCode(),e.getMessage());

         }

         return response;

     }

     //生成二维码并将其返回给前端调用者

     @PostMapping ( "generate/v2" )

     public BaseResponse generateV2(String content,HttpServletResponse servletResponse){

         BaseResponse response= new BaseResponse(StatusCode.Success);

         try {

             QRCodeUtil.createCodeToOutputStream(content,servletResponse.getOutputStream());

         } catch (Exception e){

             response= new BaseResponse(StatusCode.Fail.getCode(),e.getMessage());

         }

         return response;

}

}

<!--二维码开发工具集-->

        < dependency >

            < groupId >cn.hutool</ groupId >

            < artifactId >hutool-all</ artifactId >

            < version >4.6.10</ version >

        </ dependency >

        <!-- zxing生成二维码 -->

        < dependency >

            < groupId >com.google.zxing</ groupId >

            < artifactId >core</ artifactId >

            < version >3.3.3</ version >

        </ dependency >

        < dependency >

            < groupId >com.google.zxing</ groupId >

            < artifactId >javase</ artifactId >

            < version >3.3.3</ version >

        </ dependency >

package com.example.qrcode.Config;

import cn.hutool.extra.qrcode.QrConfig;

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.Configuration;

import java.awt.*;

@Configuration

public class QRCode {

     @Bean

     public QrConfig qrConfig(){

         QrConfig qrConfig= new QrConfig();

         qrConfig.setBackColor(Color.white.getRGB());

         qrConfig.setForeColor(Color.black.getRGB());

         return qrConfig;

     }

}

package com.example.qrcode.Service;

import cn.hutool.extra.qrcode.QrCodeUtil;

import cn.hutool.extra.qrcode.QrConfig;

import com.example.qrcode.Config.QRCode;

import org.springframework.stereotype.Service;

import org.springframework.web.bind.annotation.RequestMapping;

import javax.annotation.Resource;

import javax.servlet.http.HttpServletResponse;

import java.io.File;

import java.io.IOException;

@Service

public class QRService {

     @Resource

     QrConfig qrconig;

     public void generateFile(String content, File file){

         //生成到本地文件

         QrCodeUtil.generate(content, qrconig, file);

     }

     //输出到流

     public void generateStream(String content, HttpServletResponse response) throws IOException {

         QrCodeUtil.generate(content,qrconig, "png" ,response.getOutputStream());

     }

}

package com.example.qrcode.Controller;

import com.example.qrcode.Service.QRService;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.web.bind.annotation.RequestBody;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletResponse;

import java.io.IOException;

@RestController

public class QRController {

     @Autowired

     QRService qrService;

     @RequestMapping ( "123" )

     public void generateV3(String content, HttpServletResponse servletResponse) throws IOException {

         qrService.generateStream(content,servletResponse);

     }

}