java二维码生成并可以转换

二维码很常见,简单的二维码生成

pom中导入两个包

        
        
            com.google.zxing
            core
            3.3.0
        
        
        
            commons-fileupload
            commons-fileupload
            1.4
        

java工具类直接用

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.*;
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;
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.springframework.web.multipart.MultipartFile;
import org.apache.commons.fileupload.FileItem;
import org.springframework.web.multipart.commons.CommonsMultipartFile;

public class QRCodeUtil {
    private static final String CHARSET = "utf-8";
    public static final String FORMAT_NAME = "JPG";
    public static final String CONTENT_TYPE = "image/jpeg";
    public static final String DESTPATH = "E:/下载/";   //本地测试路径
    public static final String CODE = ".jpg";   //后缀
    public static final String FileName = "QR";   //文件名
    public static final String LOAD_PATH = DESTPATH+FileName+CODE;   //基本默认路径
    public static final String IMGPATH = "C:/Users/46145/Pictures/a/me.jpg";   //本地测试路径
    // 二维码尺寸
    private static final int QRCODE_SIZE = 1200;
    // LOGO宽度
    private static final int WIDTH = 300;
    // LOGO高度
    private static final int HEIGHT = 300;

    /**
     * 生出二维码
     */
    public 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;
    }

    /**
     * 生成中间logo
     */
    public 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();
    }

    /**
     * 读取图片
     */
    public static void encode(String content, String imgPath, String destPath, boolean needCompress) throws Exception {
        BufferedImage image = QRCodeUtil.createImage(content, imgPath, needCompress);
        if(destPath==null||destPath.isEmpty()){
            destPath=QRCodeUtil.DESTPATH+QRCodeUtil.FileName+QRCodeUtil.CODE;
        }
        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));
    }

    /**
     * 生成图片流
     */
    public static BufferedImage encode(String content, String imgPath, boolean needCompress) throws Exception {
        BufferedImage image = QRCodeUtil.createImage(content, imgPath, needCompress);
        return image;
    }

    /**
     * 生成文件
     */
    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();
        }
    }

    /**
     * 读取图片带文件路径
     */
    public static void encode(String content, String imgPath, String destPath) throws Exception {
        QRCodeUtil.encode(content, imgPath, destPath, false);
    }
    /**
     * 读取图片不带文件路径
     */
    public static void encode(String content, String destPath) throws Exception {
        QRCodeUtil.encode(content, null, destPath, false);
    }

    /**
     * 读取文件是否自适应logo
     */
    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);
    }

    /**
     * 读取文件输出流
     */
    public static void encode(String content, OutputStream output) throws Exception {
        QRCodeUtil.encode(content, null, output, false);
    }

    /**
     *  文件内容
     */
    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;
    }

    /**
     * 是否存在文件内容
     */
    public static String decode(String path) throws Exception {
        if(path==null||path.isEmpty()){
            path=QRCodeUtil.DESTPATH+QRCodeUtil.FileName+QRCodeUtil.CODE;
        }
        return QRCodeUtil.decode(new File(path));
    }
    /**
     * 生成图片并放到指定文件路径
     */
    public static int insertQR(String text,String destPath,String imgPath){
        int cg=0;
        try{
            //生成二维码
            QRCodeUtil.encode(text, imgPath, destPath, true);
            // 解析二维码
            String str = QRCodeUtil.decode(destPath);
            cg=1;
        }catch (Exception e){
            e.printStackTrace();
            cg=-1;
        }
        return cg;
    }

    /**
     * file转为MultipartFile
     */
    public static MultipartFile FileToMultipartFile(File file){
        MultipartFile multipartFile=null;
        try{
            FileItem item=QRCodeUtil.createFileItem(file.getPath());
            multipartFile=new CommonsMultipartFile(item);
        }catch (Exception e){
            multipartFile=null;
            e.printStackTrace();
        }
        return multipartFile;
    }

    /**
     * 转换为fileItem文件
     */
    public static FileItem createFileItem(String filePath) {
        File newfile=new File(filePath);
        FileItemFactory factory = new DiskFileItemFactory(16, null);
        String textFieldName = "file";
        FileItem item = factory.createItem(textFieldName, QRCodeUtil.CONTENT_TYPE, true, newfile.getName());
        int bytesRead = 0;
        byte[] buffer = new byte[8192];
        try {
            FileInputStream fis = new FileInputStream(newfile);
            OutputStream os = item.getOutputStream();
            while ((bytesRead = fis.read(buffer, 0, 8192)) != -1) {
                os.write(buffer, 0, bytesRead);
            }
            os.close();
            fis.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return item;
    }
}