二维码的后台生成及前台界面显示QRCode

今天药忘吃喽~ 2023-02-28 12:59 114阅读 0赞

### 1.导依赖 ###

<dependency>
    			<groupId>commons-codec</groupId>
    			<artifactId>commons-codec</artifactId>
    			<version>1.14</version>
    		</dependency>
    
    
    		
    		<dependency>
    			<groupId>com.google.zxing</groupId>
    			<artifactId>core</artifactId>
    			<version>3.4.0</version>
    		</dependency>

### 2.工具类 ###

package com.jdkj.charge.common.utils;
    
    import java.awt.BasicStroke;
    import java.awt.Graphics;
    import java.awt.Graphics2D;
    import java.awt.Image;
    import java.awt.Shape;
    import java.awt.geom.RoundRectangle2D;
    import java.awt.image.BufferedImage;
    import java.io.ByteArrayOutputStream;
    import java.io.File;
    import java.io.OutputStream;
    import java.util.Hashtable;
    
    import javax.imageio.ImageIO;
    
    import org.apache.commons.codec.binary.Base64;
    
    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;
    
    public class QRCodeUtil {
    
    	private static final String CHARSET = "utf-8";
    	private static final String FORMAT_NAME = "JPG";
    
    	// 二维码尺寸
    	private static final int QRCODE_SIZE = 400;
    	// LOGO宽度
    	private static final int WIDTH = 60;
    	// LOGO高度
    	private static final int HEIGHT = 60;
    
    	/**
    	 * 
    	 * @param content      文本
    	 * @param imgPath      插入logo地址
    	 * @param needCompress 压缩
    	 * @return image 图片
    	 * @throws Exception 异常
    	 */
    
    	private static BufferedImage createImage(String content, String imgPath, boolean needCompress) throws Exception {
    		Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
    		hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
    		hints.put(EncodeHintType.CHARACTER_SET, CHARSET);
    		hints.put(EncodeHintType.MARGIN, 1);
    		BitMatrix bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, QRCODE_SIZE, QRCODE_SIZE,
    				hints);
    		// 去除白边
    		bitMatrix = deleteWhite(bitMatrix);
    		int width = bitMatrix.getWidth();
    		int height = bitMatrix.getHeight();
    		BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
    
    		for (int x = 0; x < width; x++) {
    			for (int y = 0; y < height; y++) {
    				image.setRGB(x, y, bitMatrix.get(x, y) ? 0xFF000000 : 0xFFFFFFFF);
    			}
    		}
    
    		if (imgPath == null || "".equals(imgPath)) {
    			return image;
    		}
    
    		// 插入图片
    		QRCodeUtil.insertImage(image, imgPath, needCompress);
    
    		return image;
    	}
    
    	/**
    	 * 对二维码中插入图片
    	 * 
    	 * @param source       图片资源
    	 * @param imgPath      图片地址
    	 * @param needCompress 压缩属性
    	 * @throws Exception 异常
    	 */
    	private static void insertImage(BufferedImage source, String imgPath, boolean needCompress) throws Exception {
    		File file = new File(imgPath);
    		if (!file.exists()) {
    			System.err.println("" + imgPath + "   该文件不存在！");
    			return;
    		}
    
    		Image src = ImageIO.read(new File(imgPath));
    		int width = src.getWidth(null);
    		int height = src.getHeight(null);
    		if (needCompress) { // 压缩LOGO
    			if (width > WIDTH) {
    				width = WIDTH;
    			}
    			if (height > HEIGHT) {
    				height = HEIGHT;
    			}
    
    			Image image = src.getScaledInstance(width, height, Image.SCALE_SMOOTH);
    			BufferedImage tag = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
    			Graphics g = tag.getGraphics();
    			g.drawImage(image, 0, 0, null); // 绘制缩小后的图
    			g.dispose();
    			src = image;
    
    		}
    
    		// 插入LOGO
    		Graphics2D graph = source.createGraphics();
    		int x = (QRCODE_SIZE - width) / 2;
    		int y = (QRCODE_SIZE - height) / 2;
    		graph.drawImage(src, x, y, width, height, null);
    		Shape shape = new RoundRectangle2D.Float(x, y, width, width, 6, 6);
    		graph.setStroke(new BasicStroke(3f));
    		graph.draw(shape);
    		graph.dispose();
    
    	}
    
    	// 通过文件编码
    	public static void encode(String content, String imgPath, String destPath, boolean needCompress) throws Exception {
    		BufferedImage image = QRCodeUtil.createImage(content, imgPath, needCompress);
    		mkdirs(destPath);
    		ImageIO.write(image, FORMAT_NAME, new File(destPath));
    	}
    
    	// 通过字符串编码
    	public static BufferedImage encode(String content, String imgPath, boolean needCompress) throws Exception {
    		BufferedImage image = QRCodeUtil.createImage(content, imgPath, needCompress);
    		return image;
    	}
    
    	// 创建文件夹
    	public static void mkdirs(String destPath) {
    		File file = new File(destPath);
    		if (!file.exists() && !file.isDirectory()) {
    			file.mkdirs();
    		}
    	}
    
    	// 通过字符编码储存为文件
    	public static void encode(String content, String imgPath, String destPath) throws Exception {
    		QRCodeUtil.encode(content, imgPath, destPath, false);
    	}
    
    	// 编码到文件地址
    	public static void encode(String content, String destPath) throws Exception {
    		QRCodeUtil.encode(content, null, destPath, false);
    	}
    
    	// 编码到输出流并输出
    	public static void encode(String content, String imgPath, OutputStream output, boolean needCompress)
    			throws Exception {
    		BufferedImage image = QRCodeUtil.createImage(content, imgPath, needCompress);
    		ImageIO.write(image, FORMAT_NAME, output);
    	}
    
    	// 编码到输出流
    	public static void encode(String content, OutputStream output) throws Exception {
    		QRCodeUtil.encode(content, null, output, false);
    	}
    
    	// 返回Base64编码的图片
    	public static String encode(String content) throws Exception {
    		ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
    		encode(content, byteArrayOutputStream);
    		return "data:image/jpg;base64," + Base64.encodeBase64String(byteArrayOutputStream.toByteArray());
    	}
    
    	// 去除图片白边
    	private static BitMatrix deleteWhite(BitMatrix matrix) {
    		int[] rec = matrix.getEnclosingRectangle();
    		int resWidth = rec[2] + 1;
    		int resHeight = rec[3] + 1;
    
    		BitMatrix resMatrix = new BitMatrix(resWidth, resHeight);
    		resMatrix.clear();
    		for (int i = 0; i < resWidth; i++) {
    			for (int j = 0; j < resHeight; j++) {
    				if (matrix.get(i + rec[0], j + rec[1]))
    					resMatrix.set(i, j);
    			}
    		}
    		return resMatrix;
    	}
    }

### 3.controller层 ###

/**
    	 * 二维码
    	 */
    	@ResponseBody
    	@GetMapping("/getQRCode")
    	public R getQECode(Integer chargeId) throws Exception {
    		ChargeEntity charge = chargeService.getById(chargeId);
    		return R.ok().put("QRCode", QRCodeUtil.encode(charge.getHphm() + " | " + charge.getHpzl()));
    	}

### 4.界面显示 ###

HTML：
                    <img id="code" src="" alt="">
                    
                    JS：
                    $.ajax({
    			url: '/getQRCode',
    			type: 'get',
    			data: {
    				'chargeId':data.id
    			},
    			success: function(data){
    				$('#code').prop("src",data.QRCode);
    			}
    		})