本文转载自:https://blog.csdn.net/shenfuli/article/details/68923393
生成二维码的开源项目可谓是琳琅满目,SwetakeQRCode、BarCode4j、Zxing......
选择Zxing的原因可能是对 Google 公司的信赖和个人崇拜吧。
其实使用起来相当的简单。
Git 地址:
https://github.com/zxing/zxing
我们考虑使用二维码解析的业务场景: 作为一个新闻资讯类的APP,需要通过爬虫技术手段抓取大量的新闻,但往往这些新闻中有大量的图片。通过该方案可以解决一部分内容。
1、通过maven方式直接引入相关的jar包
- <!-- https://mvnrepository.com/artifact/com.google.zxing/core -->
- <dependency>
- <groupId>com.google.zxing</groupId>
- <artifactId>core</artifactId>
- <version>3.3.0</version>
- </dependency>
- <!-- https://mvnrepository.com/artifact/com.google.zxing/javase -->
- <dependency>
- <groupId>com.google.zxing</groupId>
- <artifactId>javase</artifactId>
- <version>3.3.0</version>
- </dependency>
2、提供二维码生成和解析工具类
- package com.forest.qr.utils;
- import com.google.zxing.*;
- 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;
- import javax.imageio.ImageIO;
- import java.awt.*;
- import java.awt.geom.RoundRectangle2D;
- import java.awt.image.BufferedImage;
- import java.io.File;
- import java.io.OutputStream;
- import java.util.Hashtable;
- import java.util.Random;
- /**
- * 二维码工具类
- * Created by fuli.shen on 2017/3/31.
- */
- 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;
- /**
- * 生成二维码的方法
- *
- * @param content 目标URL
- * @param imgPath LOGO图片地址
- * @param needCompress 是否压缩LOGO
- * @return 二维码图片
- * @throws Exception
- */
- 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;
- }
- /**
- * 插入LOGO
- *
- * @param source 二维码图片
- * @param imgPath LOGO图片地址
- * @param needCompress 是否压缩
- * @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();
- }
- /**
- * 生成二维码(内嵌LOGO)
- *
- * @param content 内容
- * @param imgPath LOGO地址
- * @param destPath 存放目录
- * @param needCompress 是否压缩LOGO
- * @throws Exception
- */
- 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));
- }
- /**
- * 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)
- *
- * @param destPath 存放目录
- */
- public static void mkdirs(String destPath) {
- File file = new File(destPath);
- if (!file.exists() && !file.isDirectory()) {
- file.mkdirs();
- }
- }
- /**
- * 生成二维码(内嵌LOGO)
- *
- * @param content 内容
- * @param imgPath LOGO地址
- * @param destPath 存储地址
- * @throws Exception
- */
- public static void encode(String content, String imgPath, String destPath)
- throws Exception {
- QRCodeUtil.encode(content, imgPath, destPath, false);
- }
- /**
- * 生成二维码
- *
- * @param content 内容
- * @param destPath 存储地址
- * @param needCompress 是否压缩LOGO
- * @throws Exception
- */
- public static void encode(String content, String destPath,
- boolean needCompress) throws Exception {
- QRCodeUtil.encode(content, null, destPath, needCompress);
- }
- /**
- * 生成二维码
- *
- * @param content 内容
- * @param destPath 存储地址
- * @throws Exception
- */
- public static void encode(String content, String destPath) throws Exception {
- QRCodeUtil.encode(content, null, destPath, false);
- }
- /**
- * 生成二维码(内嵌LOGO)
- *
- * @param content 内容
- * @param imgPath LOGO地址
- * @param output 输出流
- * @param needCompress 是否压缩LOGO
- * @throws Exception
- */
- 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);
- }
- /**
- * 生成二维码
- *
- * @param content 内容
- * @param output 输出流
- * @throws Exception
- */
- public static void encode(String content, OutputStream output)
- throws Exception {
- QRCodeUtil.encode(content, null, output, false);
- }
- /**
- * 解析二维码
- *
- * @param file 二维码图片
- * @return
- * @throws Exception
- */
- 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;
- }
- /**
- * 解析二维码
- *
- * @param path 二维码图片地址
- * @return 不是二维码的内容返回null,是二维码直接返回识别的结果
- * @throws Exception
- */
- public static String decode(String path) throws Exception {
- return QRCodeUtil.decode(new File(path));
- }
- public static void main(String[] args) {
- // 生成二维码
- // String text = "https://www.baidu.com/";
- // String imagePath = System.getProperty("user.dir") + "/data/1.jpg";
- String destPath = System.getProperty("user.dir") + "/data/output/";
- // QRCodeUtil.encode(text, imagePath, destPath, true);
- //验证图片是否含有二维码
- String destPath1 = System.getProperty("user.dir") + "/data/3.jpg";
- try {
- String result = decode(destPath1);
- System.out.println(result);
- }catch (Exception e){
- e.printStackTrace();
- System.out.println(destPath1+"不是二维码");
- }
- }
- }