⽣成⼆维码的两种⽅式今天项⽬上做了⼀个⼆维码的功能，在此记录⼀下。
功能描述点击⼀个超链接，弹出展⽰⼆维码的弹出框。
准备⾸先下载好⽣成⼆维码需要使⽤到的jar包，下载地址：将下载好的jar包导⼊项⽬，将以下⼯具类放到项⽬中：package com.util;import java.awt.Graphics2D;import java.awt.geom.AffineTransform;import java.awt.image.BufferedImage;import com.google.zxing.LuminanceSource;public class BufferedImageLuminanceSource extends LuminanceSource {private final BufferedImage image;private final int left;private final int top;public BufferedImageLuminanceSource(BufferedImage image) {this(image, 0, 0, image.getWidth(), image.getHeight());}public BufferedImageLuminanceSource(BufferedImage image, int left, int top, int width, int height) {super(width, height);int sourceWidth = image.getWidth();int sourceHeight = image.getHeight();if (left + width > sourceWidth || top + height > sourceHeight) {throw new IllegalArgumentException("Crop rectangle does not fit within image data.");}for (int y = top; y < top + height; y++) {for (int x = left; x < left + width; x++) {if ((image.getRGB(x, y) & 0xFF000000) == 0) {image.setRGB(x, y, 0xFFFFFFFF); // = white}}}this.image = new BufferedImage(sourceWidth, sourceHeight, BufferedImage.TYPE_BYTE_GRAY);this.image.getGraphics().drawImage(image, 0, 0, null);this.left = left;this.top = top;}public byte[] getRow(int y, byte[] row) {if (y < 0 || y >= getHeight()) {throw new IllegalArgumentException("Requested row is outside the image: " + y);}int width = getWidth();if (row == null || row.length < width) {row = new byte[width];}image.getRaster().getDataElements(left, top + y, width, 1, row);return row;}public byte[] getMatrix() {int width = getWidth();int height = getHeight();int area = width * height;byte[] matrix = new byte[area];image.getRaster().getDataElements(left, top, width, height, matrix);return matrix;}public boolean isCropSupported() {return true;}public LuminanceSource crop(int left, int top, int width, int height) {return new BufferedImageLuminanceSource(image, this.left + left, this.top + top, width, height);}public boolean isRotateSupported() {return true;}public LuminanceSource rotateCounterClockwise() {int sourceWidth = image.getWidth();int sourceHeight = image.getHeight();AffineTransform transform = new AffineTransform(0.0, -1.0, 1.0, 0.0, 0.0, sourceWidth);BufferedImage rotatedImage = new BufferedImage(sourceHeight, sourceWidth, BufferedImage.TYPE_BYTE_GRAY);Graphics2D g = rotatedImage.createGraphics();g.drawImage(image, transform, null);g.dispose();int width = getWidth();return new BufferedImageLuminanceSource(rotatedImage, top, sourceWidth - (left + width), getHeight(), width);}}package com.util;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.File;import java.io.IOException;import java.io.OutputStream;import java.util.Hashtable;import java.util.Random;import javax.imageio.ImageIO;import javax.servlet.http.HttpServletResponse;import com.google.zxing.BarcodeFormat;import com.google.zxing.BinaryBitmap;import com.google.zxing.DecodeHintType;import com.google.zxing.EncodeHintType;import com.google.zxing.MultiFormatReader;import com.google.zxing.MultiFormatWriter;import com.google.zxing.Result;import com.google.zxing.WriterException;import mon.BitMatrix;import mon.HybridBinarizer;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 = 300;// LOGO宽度private static final int WIDTH = 60;// LOGO⾼度private static final int HEIGHT = 60;private static BufferedImage createImage(String content, String imgPath, boolean needCompress) throws Exception {Hashtable hints = new Hashtable();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);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;}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LOGOif (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LOGOGraphics2D 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();}public static void encode(String content, String imgPath, String destPath, boolean needCompress) throws Exception { BufferedImage image = QRCodeUtil.createImage(content, imgPath, needCompress);mkdirs(destPath);// String file = new Random().nextInt(99999999)+".jpg";// ImageIO.write(image, FORMAT_NAME, new File(destPath+"/"+file));ImageIO.write(image, FORMAT_NAME, new File(destPath));}public static BufferedImage encode(String content, String imgPath, boolean needCompress) throws Exception {BufferedImage image = QRCodeUtil.createImage(content, imgPath, needCompress);return image;}public static void mkdirs(String destPath) {File file = new File(destPath);// 当⽂件夹不存在时，mkdirs会⾃动创建多层⽬录，区别于mkdir．(mkdir如果⽗⽬录不存在则会抛出异常)if (!file.exists() && !file.isDirectory()) {file.mkdirs();}}public static void encode(String content, String imgPath, String destPath) throws Exception {QRCodeUtil.encode(content, imgPath, destPath, false);}// 被注释的⽅法/** public static void encode(String content, String destPath, boolean* needCompress) throws Exception { QRCodeUtil.encode(content, null, destPath,* needCompress); }*/public static void encode(String content, String destPath) throws Exception {QRCodeUtil.encode(content, null, destPath, false);}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);}public static void encode(String content, OutputStream output) throws Exception {QRCodeUtil.encode(content, null, output, false);}public static String decode(File file) throws Exception {BufferedImage image;image = ImageIO.read(file);if (image == null) {return null;}BufferedImageLuminanceSource source = new BufferedImageLuminanceSource(image);BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));Result result;Hashtable hints = new Hashtable();hints.put(DecodeHintType.CHARACTER_SET, CHARSET);result = new MultiFormatReader().decode(bitmap, hints);String resultStr = result.getText();return resultStr;}public static String decode(String path) throws Exception {return QRCodeUtil.decode(new File(path));}public static void creatRrCode(String contents, int width, int height,HttpServletResponse response) {Hashtable hints = new Hashtable();hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H); //容错级别最⾼hints.put(EncodeHintType.CHARACTER_SET, "utf-8"); //设置字符编码hints.put(EncodeHintType.MARGIN, 1); //⼆维码空⽩区域,最⼩为0也有⽩边,只是很⼩,最⼩是6像素左右try {BitMatrix bitMatrix = new MultiFormatWriter().encode(contents, BarcodeFormat.QR_CODE, width, height, hints); // 1、读取⽂件转换为字节数组// ByteArrayOutputStream out = new ByteArrayOutputStream();BufferedImage image = toBufferedImage(bitMatrix);//转换成png格式的IO流ImageIO.write(image, "png", response.getOutputStream());// byte[] bytes = out.toByteArray();//// 2、将字节数组转为⼆进制// BASE64Encoder encoder = new BASE64Encoder();// binary = encoder.encodeBuffer(bytes).trim();} catch (WriterException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}/*** image流数据处理** @author ianly*/public static BufferedImage toBufferedImage(BitMatrix matrix) {int width = matrix.getWidth();int height = matrix.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, matrix.get(x, y) ? 0xFF000000 : 0xFFFFFFFF);}}return image;}}1.后台⽣成⼆维码图⽚并保存图⽚超链接以及js代码如下：[<a href="#" onclick="showCode('<%=barcode%>')" class="unline">⼆维码</a>]//⽣成⼆维码⽅法function showCode(barcode){yer.open({type: 2,title:'',cancel: function(){},area: ['300px', '300px'],fixed: false, //不固定maxmin: false,Boolean: false,content: '<%=request.getContextPath()%>/frame/showCode.do?barcode='+barcode});}后台⽣成⼆维码的代码：/*** ⽣成⼆维码*/public String showCode() {try {String barcode = request.getParameter("barcode");request.setAttribute("barcode", barcode);("barcode-------------"+barcode);// 存放在⼆维码中的内容String text = "http://127.0.0.1:8080/扫描后需要调⽤的地址?barcode="+barcode;// 嵌⼊⼆维码的图⽚路径String imgPath = "D:/md5file/20191119181532.jpg";// ⽣成的⼆维码的路径及名称String destPath = "D:/md5file/"+barcode+".jpg";//⽣成⼆维码QRCodeUtil.encode(text, imgPath, destPath, true);// 解析⼆维码String str = QRCodeUtil.decode(destPath);// 打印出解析出的内容System.out.println(str);} catch (Exception e) {e.printStackTrace();}return "showCode";}展⽰⼆维码的容器：<!-- 存放⼆维码的容器 --><img src="⼆维码图⽚保存的地址"/>2.页⾯实时⽣成⼆维码展⽰超链接以及点击事件⽅法：[<a href="#" onclick="showCode('<%=mywork.getFormcode()%>')" class="unline">⼆维码</a>] //展⽰⼆维码function showCode(barcode){yer.open({type: 2,title:'',cancel: function(){},area: ['300px', '300px'],fixed: false, //不固定maxmin: false,Boolean: false,content: '<%=request.getContextPath()%>/jsp/frame/mywork/showCode.jsp?barcode='+barcode });}此处是点击超链接直接跳到弹框页⾯，在弹框页⾯上调后台⽣成⼆维码：public void qrcode() {String barcode = request.getParameter("barcode");String content = 扫描⼆维码需要调⽤的后台地址?barcode="+barcode;//调⽤⼯具类，⽣成⼆维码QRCodeUtil.creatRrCode(content, 300,300,response); //300为图⽚⾼度和宽度}弹框页⾯代码：<%String barcode = request.getParameter("barcode");request.setAttribute("barcode", barcode);%><body><input type="hidden" name="barcode" id="barcode" value="${barcode}"><!-- 存放⼆维码的容器 --><img src="<%=request.getContextPath()%>/frame/qrcode.do?barcode=${barcode}"/></body>。
