java - 技术 - 二维码（QR Code）实现
【认识】
【java 实现生成QR code】
package pers.sun.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.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.client.j2se.BufferedImageLuminanceSource; import com.google.zxing.common.BitMatrix; import com.google.zxing.common.HybridBinarizer; import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel; /** * 二维码工具类 * @author 0_o * */ public class QRCodeUtil { //设置编码 private static final String CHARSET = "utf-8"; //图片格式名 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; /** * 编码：多个重载方法 */ //主要的编码方法：两个； 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, 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)); } //根据不同传参调用不同编码方； public static void encode(String content, String destPath) throws Exception { QRCodeUtil.encode(content, null, destPath, false); } public static void encode(String content, OutputStream output) throws Exception { QRCodeUtil.encode(content, null, output, false); } public static void encode(String content, String imgPath, String destPath) throws Exception { QRCodeUtil.encode(content, imgPath, destPath, false); } /** * 解码 ：多个重载方法 */ // public static String decode(String path) throws Exception { return QRCodeUtil.decode(new File(path)); } //主要的解析方法 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<DecodeHintType, String> hints = new Hashtable<DecodeHintType, String>(); hints.put(DecodeHintType.CHARACTER_SET, CHARSET); result = new MultiFormatReader().decode(bitmap, hints); String resultStr = result.getText(); return resultStr; } /** * 创建二维码图片 * @param content * @param imgPath * @param needCompress * @return * @throws Exception */ private static BufferedImage createImage(String content, String imgPath, boolean needCompress) throws Exception { Hashtable<EncodeHintType, Comparable> hints = new Hashtable<EncodeHintType, Comparable>(); 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; } /** * 二维码图片插入图片（内嵌图片） * @param source * @param imgPath * @param needCompress * @throws Exception */ 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(); } /** * 判断文件是否存在：不存在会创建； * @param destPath */ 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(); } } }
测试
package pers.sun.test; import org.junit.Test; import pers.sun.utils.QRCodeUtil; public class QRCodeTest { /** * 测试二维码，编码，解码功能 */ @Test public void testQRCode() { String content="hello world"; String destPath="./src/main/webapp/img/qrcodes/";//必须为.jpg图片格式，因为在QRCodeUtil中设置的图片格式为JPG String imgName=destPath+"qrcode.jpg"; try { QRCodeUtil.encode(content, imgName); } catch (Exception e) { e.printStackTrace(); } String con=null; try { con = QRCodeUtil.decode(imgName); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } System.out.println("解析内容："+con); } }
参：https://blog.csdn.net/jam_fanatic/article/details/82818857
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