java實現二維碼的生成與解析

二維碼的生成及解析的低層實現並不簡單，我們只需要知道怎么使用就可以了，參考博客：https://blog.csdn.net/jam_fanatic/article/details/82818857

1.maven中jar包引用com.google.zxing；

2.創建QRCodeUtil二維碼工具類，使用谷歌提供的幫助類BufferedImageLuminanceSource繪制二維碼。

　　生成二維碼：QRCodeUtil.encode(編碼到二維碼中的內容, 嵌入二維碼的圖片路徑, 生成的二維碼的存放路徑, 圖片是否進行壓縮);

　　解析二維碼：QRCodeUtil.decode(要解析的二維碼的存放路徑);

　　注意事項：如果你想讓別人掃描后跳轉一個頁面的話，直接在編碼的方法里，將編碼內容改為一個地址就可以了，這樣別人掃描二維碼后會自動跳轉。二維碼存的信息越多，二維碼圖片也就越復雜，容錯率也就越低，識別率也越低，並且二維碼能存的內容大小也是有限的（大概500個漢字左右）

package com.gsafety.consumer.util;

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;

import lombok.extern.slf4j.Slf4j;

/**
 *   二維碼工具類  
 */
@Slf4j
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 = 250;
    // LOGO寬度
    private static final int WIDTH = 50;
    // LOGO高度
    private static final int HEIGHT = 50;
    static SnowflakeIdWorker snowflakeIdWorker = new SnowflakeIdWorker(0,0);
    private static BufferedImage createImage(String content, String imgPath, boolean needCompress) throws Exception {
        Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
        hints.put(EncodeHintType.CHARACTER_SET, CHARSET);
        hints.put(EncodeHintType.MARGIN, 0);
        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;
    }
    /**
     *  插入LOGO          
     * @param source    二維碼圖片    
     * @param imgPath  LOGO圖片地址    
     * @param needCompress   是否壓縮    
     * @throws Exception    
     */
    private static void insertImage(BufferedImage source, String imgPath, boolean needCompress) throws Exception {
        File file = new File(imgPath);
        if (!file.exists()) {
            log.info("{}該文件不存在！",imgPath);
            return;
        }
        Image src = ImageIO.read(new File(imgPath));
        int width = src.getWidth(null);
        int height = src.getHeight(null);
        if (needCompress) { // 壓縮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); // 繪制縮小后的圖
            g.dispose();
            src = image;
        }
        // 插入LOGO
        Graphics2D graph = source.createGraphics();
        int x = (QRCODE_SIZE - width) / 2;
        int y = (QRCODE_SIZE - height) / 2;
//        graph.setClip(new RoundRectangle2D.Double(0, 0, width, height, 90, 90));
        graph.drawImage(src, x, y, width, height, null);
        Shape shape = new RoundRectangle2D.Float(x, y, width, width, 90,90);
//        graph.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
//        graph.setStroke(new BasicStroke(-1f));
        graph.draw(shape);
        graph.dispose();
    }

    /**
     *    
     *  生成二維碼(內嵌LOGO)   
     *  @param content   內容    
     *  @param imgPath   LOGO地址   
     *  @param destPath  存放目錄    
     *  @param needCompress   是否壓縮LOGO    
     *  @throws Exception    
     */
    
    public static String encode(String content, String imgPath, String destPath, boolean needCompress) throws Exception {
        BufferedImage image = QRCodeUtil.createImage(content, imgPath, needCompress);
        mkdirs(destPath);
        String random = snowflakeIdWorker.nextId();
        String file = random + ".jpg";
        ImageIO.write(image, FORMAT_NAME, new File(destPath + "/" + file));
        return "/consumer_qrcode/"+file;
    }

    /**
     *  當文件夾不存在時，mkdirs會自動創建多層目錄，區別於mkdir．(mkdir如果父目錄不存在則會拋出異常)    
     * @author  
      * @date 2013-12-11 上午10:16:36
     * @param destPath 存放目錄    
     */
    public static void mkdirs(String destPath) {
        File file = new File(destPath);
        // 當文件夾不存在時，mkdirs會自動創建多層目錄，區別於mkdir．(mkdir如果父目錄不存在則會拋出異常)
        if (!file.exists() && !file.isDirectory()) {
            file.mkdirs();
        }
    }

    /**
     *     
     *  生成二維碼(內嵌LOGO)         
     *  @param content  內容    
     *  @param imgPath  LOGO地址     
     *  @param destPath  存儲地址   
     *  @throws Exception    
     */
    public static void encode(String content, String imgPath, String destPath) throws Exception {
        QRCodeUtil.encode(content, imgPath, destPath, false);
    }

    /**
     *   
     *   生成二維碼     
     *  @param content   內容    
     *  @param destPath  存儲地址   
     *  @param needCompress   是否壓縮LOGO    
     *  @throws Exception    
     */
    public static void encode(String content, String destPath, boolean needCompress) throws Exception {
        QRCodeUtil.encode(content, null, destPath, needCompress);
    }

    /**
     *     
     *  生成二維碼  
     * @param content   內容    
     * @param destPath  存儲地址    
     * @throws Exception    
     */
    public static void encode(String content, String destPath) throws Exception {
        QRCodeUtil.encode(content, null, destPath, false);
    }

    /**
     *     
     *   生成二維碼(內嵌LOGO)     
     *  @param content  內容     
     *  @param imgPath  LOGO地址    
     *  @param output   輸出流    
     *  @param needCompress  是否壓縮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);
    }

    /**
     *    
     *  生成二維碼    
     *  @param content  內容    
     *  @param output   輸出流
     *  @throws Exception    
     */
    public static void encode(String content, OutputStream output) throws Exception {
        QRCodeUtil.encode(content, null, output, false);
    }

    /**
     *     
     *   解析二維碼     
     *   @param file 二維碼圖片     
     *   @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<DecodeHintType, Object> hints = new Hashtable<DecodeHintType, Object>();
        // 解碼設置編碼方式為：utf-8，
        hints.put(DecodeHintType.CHARACTER_SET, CHARSET);
        //優化精度
        hints.put(DecodeHintType.TRY_HARDER, Boolean.TRUE);
        //復雜模式，開啟PURE_BARCODE模式
        hints.put(DecodeHintType.PURE_BARCODE, Boolean.TRUE);
        result = new MultiFormatReader().decode(bitmap, hints);
        
        String resultStr = result.getText();
        return resultStr;
    }

    /**
     *    
     * 
     *  解析二維碼      
     * @param   path   二維碼圖片地址    
     * @return    
     * @throws  Exception    
     */
    public static String decode(String path) throws Exception {
        return QRCodeUtil.decode(new File(path));
    }
    
    public static void main(String[] args) throws Exception {
        String text = "愛你一萬年"; // 二維碼內容
         String logoPath = "D:\\work\\二維碼.png"; //嵌入二維碼的圖片路徑
        String destPath = "D:\\work";//生成二維碼的地址
        QRCodeUtil.encode(text, logoPath, destPath, false);//生成二維碼
//        String decode = QRCodeUtil.decode("D:\\work/659518998202810368.jpg");//解析二維碼
//        System.out.println(decode);//答應解析二維碼的內容
    }
}

 

待補充。。。

　　微信支付二維碼：https://www.cnblogs.com/xu-xiang/p/5797575.html

　　支付寶支付二維碼：https://www.cnblogs.com/xu-xiang/p/5797643.html