作者：紅顏禍水nvn

來(lái)源：http://suo.im/5R6ewH

步驟1

第一步首先創(chuàng)建一個(gè)普通的 Maven 項(xiàng)目，然后要實(shí)現(xiàn)二維碼功能，我們肯定要使用別人提供好的 Jar 包，這里我用的是 google 提供的 jar，pom.xml 文件配置如下：

<?xml version="1.0"?encoding="UTF-8"?> <project?xmlns="http://maven.apache.org/POM/4.0.0"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><groupId>org.javaboy</groupId><artifactId>QRCode</artifactId><version>1.0-SNAPSHOT</version><dependencies><!-- 添加 google 提供的二維碼依賴(lài) --><dependency><groupId>com.google.zxing</groupId><artifactId>core</artifactId><version>3.3.0</version></dependency></dependencies></project>

步驟2

然后使用 google 提供的工具類(lèi)，在項(xiàng)目根目錄下創(chuàng)建一個(gè) util 包，將所需要的工具類(lèi)放進(jìn)去。

工具類(lèi)1 (BufferedImageLuminanceSource)

不廢話，直接上代碼

package?org.javaboy.util;import?java.awt.Graphics2D; import?java.awt.geom.AffineTransform; import?java.awt.image.BufferedImage;import?com.google.zxing.LuminanceSource;/***?@author?bai <br/>*?@date?2020/7/1 9:27<br/>*/ 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;}@Overridepublic?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;}@Overridepublic?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;}@Overridepublic?boolean?isCropSupported()?{return?true;}@Overridepublic?LuminanceSource?crop(int?left,?int?top,?int?width,?int?height)?{return?new?BufferedImageLuminanceSource(image,?this.left + left,?this.top + top, width, height);}@Overridepublic?boolean?isRotateSupported()?{return?true;}@Overridepublic?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);}}

工具類(lèi)2 (QRCodeUtil)

這里面可以修改一些參數(shù)，例如二維碼的尺寸，寬高等等。

package?org.javaboy.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.OutputStream; import?java.util.Hashtable; import?javax.imageio.ImageIO;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.common.BitMatrix; import?com.google.zxing.common.HybridBinarizer; import?com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;/***?@author?bai <br/>*?@date?2020/7/1 9:29<br/>*/ public?class?QRCodeUtil?{private?static?final?String CHARSET =?"utf-8";private?static?final?String FORMAT_NAME =?"JPG";// 二維碼尺寸private?static?final?int?QRCODE_SIZE =?300;// LOGO寬度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;}// 插入圖片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 +?" 該文件不存在！");return;}Image src = ImageIO.read(new?File(imgPath));int?width = src.getWidth(null);int?height = src.getHeight(null);if?(needCompress) {?// 壓縮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);?// 繪制縮小后的圖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);// 當(dāng)文件夾不存在時(shí)，mkdirs會(huì)自動(dòng)創(chuàng)建多層目錄，區(qū)別于mkdir．(mkdir如果父目錄不存在則會(huì)拋出異常)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);}// 被注釋的方法/** 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));}}

啟動(dòng)類(lèi)

這一步就是調(diào)用方法，一般大家使用這種功能都是為了實(shí)現(xiàn)業(yè)務(wù)，例如常見(jiàn)的掃描二維碼跳轉(zhuǎn)鏈接（頁(yè)面），掃描二維碼出現(xiàn)文字等等。有些二維碼中間還帶有 Logo 這種圖片，將需要嵌入二維碼的圖片路徑準(zhǔn)備好就沒(méi)有問(wèn)題。

package?org.javaboy;import?org.javaboy.util.QRCodeUtil;/***?@author?bai <br/>*?@date?2020/7/1 9:31<br/>*/ public?class?QRCodeApplication?{public?static?void?main(String[] args)?throws?Exception?{// 存放在二維碼中的內(nèi)容// 二維碼中的內(nèi)容可以是文字，可以是鏈接等String text =?"http://www.baidu.com";// 嵌入二維碼的圖片路徑//String imgPath = "C:\\Users\\Administrator\\Pictures\\img\\dog.jpg";// 生成的二維碼的路徑及名稱(chēng)String destPath =?"C:\\Users\\bai\\Pictures\\img\\code"?+ System.currentTimeMillis() +?".jpg";//生成二維碼QRCodeUtil.encode(text,?null, destPath,?true);// 解析二維碼String str = QRCodeUtil.decode(destPath);// 打印出解析出的內(nèi)容System.out.println(str);} }

效果截圖

源碼奉上

碼云：https://gitee.com/jian_bo_bai/QRCode

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