java

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【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